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O'Kane SH, Chancel M, Ehrsson HH. Hierarchical and dynamic relationships between body part ownership and full-body ownership. Cognition 2024; 246:105697. [PMID: 38364444 DOI: 10.1016/j.cognition.2023.105697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 12/12/2023] [Accepted: 12/13/2023] [Indexed: 02/18/2024]
Abstract
What is the relationship between experiencing individual body parts and the whole body as one's own? We theorised that body part ownership is driven primarily by the perceptual binding of visual and somatosensory signals from specific body parts, whereas full-body ownership depends on a more global binding process based on multisensory information from several body segments. To examine this hypothesis, we used a bodily illusion and asked participants to rate illusory changes in ownership over five different parts of a mannequin's body and the mannequin as a whole, while we manipulated the synchrony or asynchrony of visual and tactile stimuli delivered to three different body parts. We found that body part ownership was driven primarily by local visuotactile synchrony and could be experienced relatively independently of full-body ownership. Full-body ownership depended on the number of synchronously stimulated parts in a nonlinear manner, with the strongest full-body ownership illusion occurring when all parts received synchronous stimulation. Additionally, full-body ownership influenced body part ownership for nonstimulated body parts, and skin conductance responses provided physiological evidence supporting an interaction between body part and full-body ownership. We conclude that body part and full-body ownership correspond to different processes and propose a hierarchical probabilistic model to explain the relationship between part and whole in the context of multisensory awareness of one's own body.
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Affiliation(s)
- Sophie H O'Kane
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
| | - Marie Chancel
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden; Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, LPNC, 38000 Grenoble, France
| | - H Henrik Ehrsson
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
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2
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Harduf A, Panishev G, Harel EV, Stern Y, Salomon R. The bodily self from psychosis to psychedelics. Sci Rep 2023; 13:21209. [PMID: 38040825 PMCID: PMC10692325 DOI: 10.1038/s41598-023-47600-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 11/16/2023] [Indexed: 12/03/2023] Open
Abstract
The sense of self is a foundational element of neurotypical human consciousness. We normally experience the world as embodied agents, with the unified sensation of our selfhood being nested in our body. Critically, the sense of self can be altered in psychiatric conditions such as psychosis and altered states of consciousness induced by psychedelic compounds. The similarity of phenomenological effects across psychosis and psychedelic experiences has given rise to the "psychotomimetic" theory suggesting that psychedelics simulate psychosis-like states. Moreover, psychedelic-induced changes in the sense of self have been related to reported improvements in mental health. Here we investigated the bodily self in psychedelic, psychiatric, and control populations. Using the Moving Rubber Hand Illusion, we tested (N = 75) patients with psychosis, participants with a history of substantial psychedelic experiences, and control participants to see how psychedelic and psychiatric experience impacts the bodily self. Results revealed that psychosis patients had reduced Body Ownership and Sense of Agency during volitional action. The psychedelic group reported subjective long-lasting changes to the sense of self, but no differences between control and psychedelic participants were found. Our results suggest that while psychedelics induce both acute and enduring subjective changes in the sense of self, these are not manifested at the level of the bodily self. Furthermore, our data show that bodily self-processing, related to volitional action, is disrupted in psychosis patients. We discuss these findings in relation to anomalous self-processing across psychedelic and psychotic experiences.
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Affiliation(s)
- Amir Harduf
- The Multidisciplinary Brain Research Center, Bar-Ilan University, 5290002, Ramat-Gan, Israel
- The Faculty of Life Sciences, Bar-Ilan University, 5290002, Ramat-Gan, Israel
| | - Gabriella Panishev
- The Multidisciplinary Brain Research Center, Bar-Ilan University, 5290002, Ramat-Gan, Israel
| | - Eiran V Harel
- Beer Yaakov-Ness Ziona Mental Health Center, Beer Yaakov, Israel
| | - Yonatan Stern
- The Multidisciplinary Brain Research Center, Bar-Ilan University, 5290002, Ramat-Gan, Israel
- Department of Cognitive Sciences, University of Haifa, 3498838, Haifa, Israel
| | - Roy Salomon
- Department of Cognitive Sciences, University of Haifa, 3498838, Haifa, Israel.
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3
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Bertoni T, Mastria G, Akulenko N, Perrin H, Zbinden B, Bassolino M, Serino A. The self and the Bayesian brain: Testing probabilistic models of body ownership through a self-localization task. Cortex 2023; 167:247-272. [PMID: 37586137 DOI: 10.1016/j.cortex.2023.06.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 03/29/2023] [Accepted: 06/19/2023] [Indexed: 08/18/2023]
Abstract
Simple multisensory manipulations can induce the illusory misattribution of external objects to one's own body, allowing to experimentally investigate body ownership. In this context, body ownership has been conceptualized as the result of the online Bayesian optimal estimation of the probability that one object belongs to the body from the congruence of multisensory inputs. This idea has been highly influential, as it provided a quantitative basis to bottom-up accounts of self-consciousness. However, empirical evidence fully supporting this view is scarce, as the optimality of the putative inference process has not been assessed rigorously. This pre-registered study aimed at filling this gap by testing a Bayesian model of hand ownership based on spatial and temporal visuo-proprioceptive congruences. Model predictions were compared to data from a virtual-reality reaching task, whereby reaching errors induced by a spatio-temporally mismatching virtual hand have been used as an implicit proxy of hand ownership. To rigorously test optimality, we compared the Bayesian model versus alternative non-Bayesian models of multisensory integration, and independently assess unisensory components and compare them to model estimates. We found that individually measured values of proprioceptive precision correlated with those fitted from our reaching task, providing compelling evidence that the underlying visuo-proprioceptive integration process approximates Bayesian optimality. Furthermore, reaching errors correlated with explicit ownership ratings at the single individual and trial level. Taken together, these results provide novel evidence that body ownership, a key component of self-consciousness, can be truly described as the bottom-up, behaviourally optimal processing of multisensory inputs.
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Affiliation(s)
- Tommaso Bertoni
- MySpace Lab, Department of Clinical Neurosciences, University Hospital of Lausanne, University of Lausanne, Lausanne, Switzerland
| | - Giulio Mastria
- MySpace Lab, Department of Clinical Neurosciences, University Hospital of Lausanne, University of Lausanne, Lausanne, Switzerland
| | - Nikita Akulenko
- MySpace Lab, Department of Clinical Neurosciences, University Hospital of Lausanne, University of Lausanne, Lausanne, Switzerland
| | - Henri Perrin
- School of Medicine, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Boris Zbinden
- MySpace Lab, Department of Clinical Neurosciences, University Hospital of Lausanne, University of Lausanne, Lausanne, Switzerland
| | | | - Andrea Serino
- MySpace Lab, Department of Clinical Neurosciences, University Hospital of Lausanne, University of Lausanne, Lausanne, Switzerland.
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4
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Finotti G, Garofalo S, Costantini M, Proffitt DR. Temporal dynamics of the Rubber Hand Illusion. Sci Rep 2023; 13:7526. [PMID: 37160924 PMCID: PMC10170134 DOI: 10.1038/s41598-023-33747-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Accepted: 04/18/2023] [Indexed: 05/11/2023] Open
Abstract
It is widely accepted that the representation of the body is not fixed and immutable, but rather flexible and constantly updated based on a continuous stream of multisensory information. This mechanism can be very useful to adapt to several situations, but it would not be adaptive if the body representation was too malleable or if it wasn't capable of restoring its integrity after a transient modification. Here we used the Rubber Hand Illusion (RHI) to investigate how quickly the body representation can be modified. Previous studies have investigated the timing of the onset and offset of the illusion, however, they did not assess a fine temporal resolution. Here, we used a potentiometer to record a moment-by-moment rating of the feeling of owning the RH for two minutes during the visuo-tactile stimulation and two minutes following the stimulation. Our results suggest that the feeling of Ownership is already established during the first 19 s of stimulation then it continues to grow, but at a much slower pace. The feeling of Ownership disappears within 66 s from the end of the stimulation. This work sheds new light on the temporal dynamics of the RHI and the malleability of the body self-consciousness.
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Affiliation(s)
- Gianluca Finotti
- Department of Psychology, University of Virginia, Charlottesville, Virginia, USA.
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology, University of Bologna, Via Rasi e Spinelli 176, 47521, Cesena, FC, Italy.
| | - Sara Garofalo
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology, University of Bologna, Via Rasi e Spinelli 176, 47521, Cesena, FC, Italy
| | - Marcello Costantini
- Department of Psychological, Health and Territorial Sciences, University G. d'Annunzio, Chieti-Pescara, Italy
| | - Dennis R Proffitt
- Department of Psychology, University of Virginia, Charlottesville, Virginia, USA
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5
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Torregrossa LJ, Blain SD, Snodgress MA, Park S. Multidimensional schizotypy and embodied emotions. Front Psychol 2023; 14:1141799. [PMID: 37179864 PMCID: PMC10166830 DOI: 10.3389/fpsyg.2023.1141799] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Accepted: 04/03/2023] [Indexed: 05/15/2023] Open
Abstract
Background Disembodiment and socio-emotional deficits are core features of the schizophrenia spectrum from the prodromal stages to chronic illness. A recent study documented anomalous emotional embodiment in individuals with schizophrenia. Although bodily self disturbances have been shown to precede and predict psychosis onset in at-risk populations, the etiology of anomalous emotional embodiment remains largely unexplored. The present study investigated bodily maps of emotions in relation to schizotypy to extend our understanding of embodied emotions in the schizophrenia spectrum. Methods A total of 419 participants (312 female; 19.50 ± 1.22 years) completed a topographical body mapping task where they reported patterns of embodiment experienced in the context of eleven different emotions and a neutral state (EmBODY). Embodied emotions were investigated in relation to multidimensional schizotypy. Results Individuals with elevated negative schizotypy experienced embodied emotions with higher intensity (r = 0.16, p = 0.003) but lower clarity (i.e., endorsing activation and deactivation in the same bodily location; β = -0.28, 95% CI [-0.54, -0.03], Z = 2.25, p=0.02) and endorsed more incongruent bodily sensations of emotions (i.e., reporting bodily activation in the context of a low-arousal emotion, r = 0.12, p = 0.05; reporting bodily deactivation in the context of high-arousal emotions, r = 0.13, p = 0.02). In line with the anomalous emotional embodiment documented in individuals with schizophrenia, some of these differences were particularly notable for low-arousal emotions. Discussion These results reveal negative schizotypy as a significant correlate of differences in emotional embodiment. More work is needed to link these differences to the anomalous bodily sensations of emotions documented in schizophrenia and assess their functional impact.
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Affiliation(s)
- Lénie J. Torregrossa
- Department of Psychology, Vanderbilt University, Nashville, TN, United States
- Department of Psychiatry, Vanderbilt University Medical Center, Nashville, TN, United States
| | - Scott D. Blain
- Department of Psychology, Vanderbilt University, Nashville, TN, United States
- Department of Psychiatry, University of Michigan, Ann Arbor, MI, United States
| | - Matthew A. Snodgress
- Department of Psychology, Vanderbilt University, Nashville, TN, United States
- Department of Psychology, University of Minnesota, Minneapolis, MN, United States
| | - Sohee Park
- Department of Psychology, Vanderbilt University, Nashville, TN, United States
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Kassim FM, Mark Lim JH, Albrecht MA, Martin-Iverson MT. Dexamphetamine influences funneling illusion based on psychometric score. Hum Psychopharmacol 2023; 38:e2862. [PMID: 36799101 DOI: 10.1002/hup.2862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 02/18/2023]
Abstract
OBJECTIVES Our team previously showed that like the experience of the rubber hand illusion (RHI) in people with schizophrenia and their offspring¸ dexamphetamine administration to healthy volunteers increases the stimulus binding windows (BWs) in RHI. It is not clear if similar expansions of BWs are present for unimodal illusions. Studies have also shown that subjective or objective effects of amphetamine would be linked to between-person variations in personality measures. Therefore, we aimed to examine the effect of dexamphetamine (DEX), a dopamine-releasing stimulant, on illusory perception using unimodal sensory stimuli (Tactile Funneling Illusion [TFI]) across both temporal and spatial variables. We further examined the relationship between changes in psychometric scores and changes in illusion perception induced by dexamphetamine. METHODS Healthy subjects (N = 20) participated in a randomized, double-blind, counter-balanced, placebo-controlled, cross-over study. The effects of dexamphetamine (0.45 mg/kg, PO, q.d.) on funneling and error of spatial localization (EL) were examined using TFI. Psychotomimetic effects were assessed using a battery of psychological measures. RESULTS Dexamphetamine did not significantly increased the funneling illusion (p = 0.88) or EL (p = 0.5), relative to placebo. However, the degree of change in psychometric scores following dexamphetamine positively correlated with changes in funneling (ρ = 0.48, p = 0.03, n = 20), mainly at 0 ms delay condition (ρ = 0.6, p = 0.004, n = 20). CONCLUSION Unlike multimodal illusions, alteration of BWs does not occur for unimodal illusions after administration of a dopamine-releasing agent. However, our findings indicate that moderate release of dopamine, through its psychotomimetic effect, indirectly influences unimodal illusion.
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Affiliation(s)
- Faiz M Kassim
- Neuropsychopharmacology Research Unit, School of Biomedical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - J H Mark Lim
- Neuropsychopharmacology Research Unit, School of Biomedical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Matthew A Albrecht
- Western Australian Centre for Road Safety Research, School of Psychological Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Mathew T Martin-Iverson
- Neuropsychopharmacology Research Unit, School of Biomedical Sciences, University of Western Australia, Perth, Western Australia, Australia
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7
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Zouraraki C, Kyriklaki A, Economou E, Giakoumaki SG. The moderating role of early traumatic experiences on the association of schizotypal traits with visual perception. Scand J Psychol 2023; 64:10-20. [PMID: 35833570 DOI: 10.1111/sjop.12859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 05/11/2022] [Accepted: 06/24/2022] [Indexed: 01/11/2023]
Abstract
The findings on the association of schizotypal traits with the perception of visual illusions are scarce and inconsistent and have not taken into consideration potential effects of childhood traumatic experiences, a risk factor for schizophrenia-spectrum conditions. Thus, the present study addressed the question of potential moderating effects of early traumatic experiences on the association between different aspects of schizotypal traits with the perception of the Müller-Lyer and Navon's Hierarchical Letters (NHL) illusions. The study revealed that (a) increased suspiciousness was associated with increased liability to the Müller-Lyer illusion, when the exposure to traumatic events was high, whereas the opposite pattern was true when the exposure to traumatic events was low; (b) negative schizotypy was associated with more accurate global perception, and high disorganized schizotypy was associated with superior accuracy when target letters were present during the NHL illusion, when early traumatic experiences were at lower levels; and (c) high negative, disorganized, and total schizotypy were associated with lower accuracy when target letters were present in the NHL paradigm, when early traumatic experiences were at higher levels. The findings of the study suggest that early traumatic events differentially moderate the relationship between various aspects of schizotypal traits and visual perceptual processing.
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Affiliation(s)
- Chrysoula Zouraraki
- Laboratory of Neuropsychology, Department of Psychology, University of Crete, Rethymno, Crete, Greece.,University of Crete Research Center for the Humanities, The Social and Educational Sciences (UCRC), University of Crete, Rethymno, Crete, Greece
| | - Andriani Kyriklaki
- Department of Social Medicine, School of Medicine, University of Crete, Heraklion, Crete, Greece
| | - Elias Economou
- Laboratory of Experimental Psychology, Department of Psychology, University of Crete, Rethymno, Crete, Greece
| | - Stella G Giakoumaki
- Laboratory of Neuropsychology, Department of Psychology, University of Crete, Rethymno, Crete, Greece.,University of Crete Research Center for the Humanities, The Social and Educational Sciences (UCRC), University of Crete, Rethymno, Crete, Greece
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8
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Body transfer illusions in the schizophrenia spectrum: a systematic review. SCHIZOPHRENIA 2022; 8:103. [PMID: 36424451 PMCID: PMC9691625 DOI: 10.1038/s41537-022-00314-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 11/09/2022] [Indexed: 11/26/2022]
Abstract
Schizophrenia has been viewed as a disorder of the self. Accordingly, the question arises if and how senses of ownership and agency are impaired in schizophrenia. To address this question, several body transfer illusions (BTIs) have been investigated in schizophrenia patients and other schizophrenia spectrum (SCZ-S) populations. The objective of the study was to systematically review the current evidence from BTIs in the SCZ-S. A systematic literature search in PubMed and CENTRAL (search date: February 12, 2022) was conducted on BTI studies carried out in SCZ-S populations. Studies were included if they were published in English after peer review, reported original research data, related to the SCZ-S, and used a BTI as its study method. Conference papers, study protocols, and reviews were excluded. For each included BTI study, various study characteristics and outcomes were retrieved, and a risk-of-bias score was calculated based on six study quality criteria. K = 40 studies were identified, of which k = 20 studies met the eligibility criteria. For BTI paradigms using visuotactile stimulation, most studies found elevated sense of ownership ratings in SCZ-S populations compared to healthy controls (HC). Implicit illusion measures (e.g., proprioceptive drift), in turn, did not generally indicate elevated embodiment levels in SCZ-S populations. Likewise, no consistent group differences emerged between SCZ-S populations and HC with respect to BTI paradigms using visuomotor stimulation. Furthermore, BTI vividness was found to correlate significantly with core symptoms of schizophrenia and various subclinical characteristics related to the SCZ-S. In line with the self-disturbance hypothesis, SCZ-S populations appear to be affected by aberrations in bodily self-awareness. Review registration: PROSPERO (identifier: CRD42022287960).
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9
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Seymour K, Kaliuzhna M. Self-monitoring in schizophrenia: Weighting exteroceptive visual signals against self-generated vestibular cues. Schizophr Res Cogn 2022; 29:100256. [PMID: 35600051 PMCID: PMC9117687 DOI: 10.1016/j.scog.2022.100256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/29/2022] [Accepted: 05/09/2022] [Indexed: 11/01/2022] Open
Abstract
Disturbances in self-monitoring are core symptoms of schizophrenia. Some research suggests an over-reliance on exteroceptive cues and a reduced weighting of self-generated interoceptive signals to guide perception. The vestibular sense provides important self-generated information about the body in space. Alterations of vestibular function are reported in schizophrenia, but it is unknown whether internally generated vestibular information is discounted in favour of exteroceptive input. In this study, we test for evidence of an over-reliance on exteroceptive visual cues and a reduced weighting of vestibular signals in guiding perception. In a group of individuals with schizophrenia and healthy controls, we used a well-studied visual illusion - the Tilt Illusion - to probe the respective weight given to visual and vestibular cues in judging line orientation. The Tilt Illusion reveals that perceived orientation of a vertical grating is biased by the orientation in its surround. This illusion increases when the head is tilted, due to the reduced reliability of vestibular information that would otherwise provide an internally generated reference for vertical. We predicted that an over-reliance on exteroceptive cues in schizophrenia would lead to a reduced susceptibility to the effects of head position on Tilt Illusion strength. We find no difference between patients and controls. Both groups show comparable Tilt Illusion magnitudes that increase when the head is tilted. Thus, our findings suggest that chronic patients with schizophrenia adequately combine self-generated vestibular cues and exteroceptive visual input to judge line verticality. A stronger reliance on exteroceptive information over internally generated signals in guiding perception is not evident in our data. Deficits in self-monitoring might therefore be modality specific or state dependant.
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Affiliation(s)
- Kiley Seymour
- School of Psychology, Western Sydney University, New South Wales, Australia.,The MARCS Institute for Brain, Behaviour and Development, Western Sydney University, New South Wales, Australia
| | - Mariia Kaliuzhna
- Clinical and Experimental Psychopathology Group, Department of Psychiatry, University of Geneva, Switzerland
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10
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Slater M, Ehrsson HH. Multisensory Integration Dominates Hypnotisability and Expectations in the Rubber Hand Illusion. Front Hum Neurosci 2022; 16:834492. [PMID: 35782045 PMCID: PMC9244625 DOI: 10.3389/fnhum.2022.834492] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 05/04/2022] [Indexed: 12/02/2022] Open
Abstract
Some recent papers by P. Lush and colleagues have argued that the rubber hand illusion (RHI), where participants can feel a rubber hand as their own under appropriate multisensory stimulation, may be caused mainly by hypnotic suggestibility and expectations (demand characteristics). These papers rely primarily on a study with 353 participants who took part in a RHI experiment carried out in a classical way with brush stroking. Participants experienced a synchronous condition where the rubber hand was seen to be touched in synchrony with touch felt on their corresponding hidden real hand, or the touches were applied asynchronously as a control. Each participant had a related measure of their hypnotisability on a scale known as the Sussex-Waterloo Scale of Hypnotisability (SWASH). The authors found a correlation between the questionnaire ratings of the RHI in the synchronous condition and the SWASH score. From this, they concluded that the RHI is largely driven by suggestibility and further proposed that suggestibility and expectations may even entirely explain the RHI. Here we examine their claims in a series of extensive new analyses of their data. We find that at every level of SWASH, the synchronous stimulation results in greater levels of the illusion than the asynchronous condition; moreover, proprioceptive drift is greater in the synchronous case at every level of SWASH. Thus, while the level of hypnotisability does modestly influence the subjective reports (higher SWASH is associated with somewhat higher illusion ratings), the major difference between the synchronous and asynchronous stimulation is always present. Furthermore, by including in the model the participants' expectancy ratings of how strongly they initially believed they would experience the RHI in the two conditions, we show that expectations had a very small effect on the illusion ratings; model comparisons further demonstrate that the multisensory condition is two-to-three-times as dominant as the other factors, with hypnotisability contributing modestly and expectations negligibly. Thus, although the results indicate that trait suggestibility may modulate the RHI, presumably through intersubject variations in top-down factors, the findings also suggest that the primary explanation for the RHI is as a multisensory bodily illusion.
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Affiliation(s)
- Mel Slater
- Event Lab, Department of Clinical Psychology and Psychobiology, University of Barcelona, Barcelona, Spain
- Institute of Neurosciences of the University of Barcelona, Barcelona, Spain
| | - H. Henrik Ehrsson
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
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11
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He J, Ren H, Li J, Dong M, Dai L, Li Z, Miao Y, Li Y, Tan P, Gu L, Chen X, Tang J. Deficits in Sense of Body Ownership, Sensory Processing, and Temporal Perception in Schizophrenia Patients With/Without Auditory Verbal Hallucinations. Front Neurosci 2022; 16:831714. [PMID: 35495040 PMCID: PMC9046910 DOI: 10.3389/fnins.2022.831714] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 03/15/2022] [Indexed: 11/13/2022] Open
Abstract
It has been claimed that individuals with schizophrenia have difficulty in self-recognition and, consequently, are unable to identify the sources of their sensory perceptions or thoughts, resulting in delusions, hallucinations, and unusual experiences of body ownership. The deficits also contribute to the enhanced rubber hand illusion (RHI; a body perception illusion, induced by synchronous visual and tactile stimulation). Evidence based on RHI paradigms is emerging that auditory information can make an impact on the sense of body ownership, which relies on the process of multisensory inputs and integration. Hence, we assumed that auditory verbal hallucinations (AVHs), as an abnormal auditory perception, could be linked with body ownership, and the RHI paradigm could be conducted in patients with AVHs to explore the underlying mechanisms. In this study, we investigated the performance of patients with/without AVHs in the RHI. We administered the RHI paradigm to 80 patients with schizophrenia (47 with AVHs and 33 without AVHs) and 36 healthy controls. We conducted the experiment under two conditions (synchronous and asynchronous) and evaluated the RHI effects by both objective and subjective measures. Both patient groups experienced the RHI more quickly and strongly than HCs. The RHI effects of patients with AVHs were significantly smaller than those of patients without AVHs. Another important finding was that patients with AVHs did not show a reduction in RHI under asynchronous conditions. These results emphasize the disturbances of the sense of body ownership in schizophrenia patients with/without AVHs and the associations with AVHs. Furthermore, it is suggested that patients with AVHs may have multisensory processing dysfunctions and internal timing deficits.
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Affiliation(s)
- Jingqi He
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Honghong Ren
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Jinguang Li
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
- Affiliated Wuhan Mental Health Center, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Min Dong
- Guangdong Mental Health Center, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Lulin Dai
- Department of Neurosurgery, Center for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Zhijun Li
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Yating Miao
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Yunjin Li
- Department of Pathology, School of Basic Medical Sciences, Central South University, Changsha, China
| | - Peixuan Tan
- Department of Medical Psychology and Behavioral Medicine, School of Public Health, Guangxi Medical University, Nanning, China
| | - Lin Gu
- RIKEN Center for Advanced Intelligence Project, Tokyo, Japan
- Research Center for Advanced Science and Technology (RCAST), University of Tokyo, Tokyo, Japan
| | - Xiaogang Chen
- Department of Psychiatry, National Clinical Research Center for Mental Disorders, The Second Xiangya Hospital of Central South University, Changsha, China
- *Correspondence: Xiaogang Chen,
| | - Jinsong Tang
- Department of Psychiatry, Sir Run-Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- Zigong Mental Health Center, Zigong, China
- Jinsong Tang,
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12
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Hsu TY, Zhou JF, Yeh SL, Northoff G, Lane TJ. Intrinsic neural activity predisposes susceptibility to a body illusion. Cereb Cortex Commun 2022; 3:tgac012. [PMID: 35382092 PMCID: PMC8976633 DOI: 10.1093/texcom/tgac012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 02/21/2022] [Accepted: 03/01/2022] [Indexed: 11/13/2022] Open
Abstract
Susceptibility to the rubber hand illusion (RHI) varies. To date, however, there is no consensus explanation of this variability. Previous studies, focused on the role of multisensory integration, have searched for neural correlates of the illusion. But those studies have failed to identify a sufficient set of functionally specific neural correlates. Because some evidence suggests that frontal α power is one means of tracking neural instantiations of self, we hypothesized that the higher the frontal α power during the eyes-closed resting state, the more stable the self. As a corollary, we infer that the more stable the self, the less susceptible are participants to a blurring of boundaries—to feeling that the rubber hand belongs to them. Indeed, we found that frontal α amplitude oscillations negatively correlate with susceptibility. Moreover, since lower frequencies often modulate higher frequencies, we explored the possibility that this might be the case for the RHI. Indeed, some evidence suggests that high frontal α power observed in low-RHI participants is modulated by δ frequency oscillations. We conclude that while neural correlates of multisensory integration might be necessary for the RHI, sufficient explanation involves variable intrinsic neural activity that modulates how the brain responds to incompatible sensory stimuli.
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Affiliation(s)
- Tzu-Yu Hsu
- Graduate Institute of Mind, Brain, and Consciousness, Taipei Medical University, Taipei, Taiwan
- Brain and Consciousness Research Centre, TMU Shuang Ho Hospital, New Taipei City, Taiwan
| | - Ji-Fan Zhou
- Department of Psychology and Behavioral Sciences, Zhejiang University, Hang Zhou, China
| | - Su-Ling Yeh
- Department of Psychology, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Brain and Mind Sciences, National Taiwan University, Taipei, Taiwan
- Neurobiology and Cognitive Neuroscience Center, National Taiwan University, Taipei, Taiwan
- Center for Artificial Intelligence and Advanced Robotics, National Taiwan University, Taipei, Taiwan
| | - Georg Northoff
- Institute of Mental Health Research, University of Ottawa, Ottawa, Canada
| | - Timothy Joseph Lane
- Graduate Institute of Mind, Brain, and Consciousness, Taipei Medical University, Taipei, Taiwan
- Brain and Consciousness Research Centre, TMU Shuang Ho Hospital, New Taipei City, Taiwan
- Institute of European and American Studies, Academia Sinica, Taipei, Taiwan
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13
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Barbato M, Arora T, Al Hemeiri S, AlJassmi MA. Looking within: Interoceptive sensibility in young adults with psychotic-like experiences. Early Interv Psychiatry 2021; 15:1705-1712. [PMID: 33442933 DOI: 10.1111/eip.13117] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 12/13/2020] [Accepted: 01/04/2021] [Indexed: 02/06/2023]
Abstract
AIM Interoception is the ability to sense internal bodily changes and research indicates that it may play a role in the development of mental illness. In recent years, preliminary evidence has shown that interoception is impaired in people with psychosis. Interoceptive sensibility, a meta-cognitive aspect of interoception, has never been studied across the psychosis continuum. The present study aimed at assessing interoceptive sensibility in youth with psychotic-like experiences. METHOD We invited a sample of young adults (N = 609; age 19-21 years) to complete an online survey that included a measure of interoceptive sensibility (the Multidimensional Assessment of Interoceptive Awareness-2) and the Community Assessment of Psychotic Experiences-Positive Scale -15 (CAPE-P15). Using the recommended cutoff for the CAPE-P15, the overall sample was divided into two groups (high/low risk for psychosis). RESULTS Significant group differences were observed in several dimensions of interoceptive sensibility. A logistic regression analysis indicated that scores in the subscales of Not-Distracting, Not-Worrying, Attention-Regulation, Emotional Awareness, Body Listening, and Trusting significantly predicted increased risk for psychosis. CONCLUSION Abnormal interoceptive sensibility may be a vulnerability marker for psychosis. These results, however, await further validation from additional comprehensive, longitudinal studies. Enhanced interoceptive sensibility has been reported following contemplative training, thus creating opportunities for future interventions to delay or prevent psychotic illness.
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Affiliation(s)
- Mariapaola Barbato
- Department of Psychology, College of Natural and Health Sciences, Zayed University, Dubai, United Arab Emirates
| | - Teresa Arora
- Department of Psychology, College of Natural and Health Sciences, Zayed University, Dubai, United Arab Emirates
| | | | - Maryam A AlJassmi
- Department of Psychology, College of Natural and Health Sciences, Zayed University, Dubai, United Arab Emirates
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14
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Muller AM, Dalal TC, Stevenson RA. Schizotypal personality traits and multisensory integration: An investigation using the McGurk effect. Acta Psychol (Amst) 2021; 218:103354. [PMID: 34174491 DOI: 10.1016/j.actpsy.2021.103354] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 06/04/2021] [Accepted: 06/10/2021] [Indexed: 12/14/2022] Open
Abstract
Multisensory integration, the process by which sensory information from different sensory modalities are bound together, is hypothesized to contribute to perceptual symptomatology in schizophrenia, in whom multisensory integration differences have been consistently found. Evidence is emerging that these differences extend across the schizophrenia spectrum, including individuals in the general population with higher levels of schizotypal traits. In the current study, we used the McGurk task as a measure of multisensory integration. We measured schizotypal traits using the Schizotypal Personality Questionnaire (SPQ), hypothesizing that higher levels of schizotypal traits, specifically Unusual Perceptual Experiences and Odd Speech subscales, would be associated with decreased multisensory integration of speech. Surprisingly, Unusual Perceptual Experiences were not associated with multisensory integration. However, Odd Speech was associated with multisensory integration, and this association extended more broadly across the Disorganized factor of the SPQ, including Odd or Eccentric Behaviour. Individuals with higher levels of Odd or Eccentric Behaviour scores also demonstrated poorer lip-reading abilities, which partially explained performance in the McGurk task. This suggests that aberrant perceptual processes affecting individuals across the schizophrenia spectrum may relate to disorganized symptomatology.
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Affiliation(s)
- Anne-Marie Muller
- Department of Psychology, University of Western Ontario, London, ON, Canada; Brain and Mind Institute, University of Western Ontario, London, ON, Canada
| | - Tyler C Dalal
- Department of Psychology, University of Western Ontario, London, ON, Canada; Brain and Mind Institute, University of Western Ontario, London, ON, Canada
| | - Ryan A Stevenson
- Department of Psychology, University of Western Ontario, London, ON, Canada; Brain and Mind Institute, University of Western Ontario, London, ON, Canada.
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15
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Jakobson LS, Rigby SN. Alexithymia and Sensory Processing Sensitivity: Areas of Overlap and Links to Sensory Processing Styles. Front Psychol 2021; 12:583786. [PMID: 34108902 PMCID: PMC8182761 DOI: 10.3389/fpsyg.2021.583786] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 04/14/2021] [Indexed: 01/28/2023] Open
Abstract
Alexithymia is a dimensional trait characterized by difficulties identifying and describing feelings and an externally oriented thinking (EOT) style. Here, we explored interrelationships between alexithymia and measures assessing how individuals process and regulate their responses to environmental and body-based cues. Young adults (N = 201) completed self-report questionnaires assessing alexithymia, sensory processing sensitivity (SPS), interoceptive accuracy (IA), sensory processing styles, and current levels of depression, anxiety, and stress. Whereas EOT was related to low orienting sensitivity, problems with emotional appraisal (difficulties identifying feelings/difficulties describing feelings) were related to heightened sensory sensitivity. In addition, features of SPS improved the prediction of alexithymia above and beyond that accounted for by IA. We suggest that EOT is linked to problems maintaining a representation of one’s emotions in working memory and that low IA and problems with emotional appraisal are linked to atypicalities in sensory processing that may impact embodiment. A latent profile analysis revealed five classes of individuals distinguished by the relative strength of different alexithymic traits and by differences in IA and sensory processing styles. The classes identified included two lexithymic, one modal, and two alexithymic groups, showing different susceptibilities to SPS. Overall, our findings lend support to the view that alexithymia is associated with atypicalities in both bottom–up and top–down processes that impact emotion processing and regulation. They also raise the possibility that individuals with different alexithymia subtypes may differ with regard to a range of factors, including not only SPS but also early life experiences, mental health outcomes, and susceptibility to various personality disorders.
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Affiliation(s)
- Lorna S Jakobson
- Department of Psychology, University of Manitoba, Winnipeg, MB, Canada
| | - Sarah N Rigby
- Department of Psychology, University of Manitoba, Winnipeg, MB, Canada
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16
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Spaccasassi C, Frigione I, Maravita A. Bliss in and Out of the Body: The (Extra)Corporeal Space Is Impervious to Social Pleasant Touch. Brain Sci 2021; 11:brainsci11020225. [PMID: 33673297 PMCID: PMC7917648 DOI: 10.3390/brainsci11020225] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/08/2021] [Accepted: 02/10/2021] [Indexed: 11/16/2022] Open
Abstract
Slow, gentle stimulation of hairy skin is generally accompanied by hedonic sensations. This phenomenon, also known as (positive) affective touch, is likely to be the basis of affiliative interactions with conspecifics by promoting inter-individual bindings. Previous studies on healthy humans have demonstrated that affective touch can remarkably impact behavior. For instance, by administering the Rubber Hand Illusion (RHI) paradigm, the embodiment of a fake hand enhances after a slow, affective touch compared to a fast, neutral touch. However, results coming from this area are not univocal. In addition, there are no clues in the existing literature on the relationship between affective touch and the space around our body. To overcome these lacks, we carried out two separate experiments where participants underwent a RHI paradigm (Experiment 1) and a Visuo-Tactile Interaction task (Experiment 2), designed to tap into body representation and peripersonal space processing, respectively. In both experiments, an affective touch (CT-optimal, 3 cm/s) and neutral touch (CT-suboptimal, 18 cm/s) were delivered by the experimenter on the dorsal side of participants’ hand through a “skin to skin” contact. In Experiment 1, we did not find any modulation of body representation—not at behavioral nor at a physiological level—by affective touch. In Experiment 2, no visuo-tactile spatial modulation emerged depending upon the pleasantness of the touch received. These null findings are interpreted in the light of the current scientific context where the real nature of affective touch is often misguided, and they offer the possibility to pave the way for understanding the real effects of affective touch on body/space representation.
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Affiliation(s)
- Chiara Spaccasassi
- Centre for Studies and Research in Cognitive Neuroscience, ‘Alma Mater Studiorum’, Department of Psychology, Cesena Campus, Bologna University, 47521 Cesena, Italy
- Correspondence:
| | - Ivana Frigione
- Department of Psychology, University of Milano-Bicocca, Piazza Ateneo Nuovo 1, 20126 Milano, Italy; (I.F.); (A.M.)
| | - Angelo Maravita
- Department of Psychology, University of Milano-Bicocca, Piazza Ateneo Nuovo 1, 20126 Milano, Italy; (I.F.); (A.M.)
- Milan Centre for Neurosciences, 20126 Milano, Italy
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17
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Dalal TC, Muller AM, Stevenson RA. The Relationship Between Multisensory Temporal Processing and Schizotypal Traits. Multisens Res 2021; 34:1-19. [PMID: 33706260 DOI: 10.1163/22134808-bja10044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 01/06/2021] [Indexed: 11/19/2022]
Abstract
Recent literature has suggested that deficits in sensory processing are associated with schizophrenia (SCZ), and more specifically hallucination severity. The DSM-5's shift towards a dimensional approach to diagnostic criteria has led to SCZ and schizotypal personality disorder (SPD) being classified as schizophrenia spectrum disorders. With SCZ and SPD overlapping in aetiology and symptomatology, such as sensory abnormalities, it is important to investigate whether these deficits commonly reported in SCZ extend to non-clinical expressions of SPD. In this study, we investigated whether levels of SPD traits were related to audiovisual multisensory temporal processing in a non-clinical sample, revealing two novel findings. First, less precise multisensory temporal processing was related to higher overall levels of SPD symptomatology. Second, this relationship was specific to the cognitive-perceptual domain of SPD symptomatology, and more specifically, the Unusual Perceptual Experiences and Odd Beliefs or Magical Thinking symptomatology. The current study provides an initial look at the relationship between multisensory temporal processing and schizotypal traits. Additionally, it builds on the previous literature by suggesting that less precise multisensory temporal processing is not exclusive to SCZ but may also be related to non-clinical expressions of schizotypal traits in the general population.
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Affiliation(s)
- Tyler C Dalal
- 1Department of Psychology, University of Western Ontario, London, ON, M6G 2N5, Canada
- 2Brain and Mind Institute, University of Western Ontario, London, ON, M6G 2N5, Canada
| | - Anne-Marie Muller
- 1Department of Psychology, University of Western Ontario, London, ON, M6G 2N5, Canada
- 2Brain and Mind Institute, University of Western Ontario, London, ON, M6G 2N5, Canada
| | - Ryan A Stevenson
- 1Department of Psychology, University of Western Ontario, London, ON, M6G 2N5, Canada
- 2Brain and Mind Institute, University of Western Ontario, London, ON, M6G 2N5, Canada
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18
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Zopf R, Boulton K, Langdon R, Rich AN. Perception of visual-tactile asynchrony, bodily perceptual aberrations, and bodily illusions in schizophrenia. Schizophr Res 2021; 228:534-540. [PMID: 33234423 DOI: 10.1016/j.schres.2020.11.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 10/12/2020] [Accepted: 11/16/2020] [Indexed: 11/26/2022]
Abstract
Body perception can be altered in individuals with schizophrenia resulting in experiences of undefined boundaries, loss of ownership, and size changes. These individuals may also be more susceptible to the rubber hand illusion (RHI: an illusion of body perception that can also be induced in neurotypical populations), but the findings are mixed. Furthermore, the perception of multisensory timing, which is thought to be fundamental for body perception, is altered in schizophrenia. We tested whether altered perception of the temporal relationship between visual and tactile signals in schizophrenia predicts self-reported perceptual aberrations and RHI susceptibility. We found that the sensitivity to detect temporal asynchronies is reduced in schizophrenia and this is a significant predictor for bodily perceptual symptoms. In contrast, we found no evidence for a direct relationship between asynchrony detection sensitivity and RHI susceptibility. Instead, our findings suggest that experiencing more bodily perceptual symptoms increases the likelihood of endorsing unusual bodily experiences, resulting in higher RHI self-ratings but not higher proprioceptive drift scores. Our findings provide new insight into factors that may underlie the report of unusual body perceptions in schizophrenia.
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Affiliation(s)
- Regine Zopf
- Department of Cognitive Science, Faculty of Medical, Health & Human Sciences, Macquarie University, Sydney, Australia; Perception in Action Research Centre, Faculty of Medical, Health & Human Sciences, Macquarie University, Sydney, Australia; Body Image and Ingestion Group, Macquarie University, Sydney, Australia.
| | - Kelsie Boulton
- Department of Psychology, Faculty of Medical, Health & Human Sciences, Macquarie University, Sydney, Australia
| | - Robyn Langdon
- Department of Cognitive Science, Faculty of Medical, Health & Human Sciences, Macquarie University, Sydney, Australia
| | - Anina N Rich
- Department of Cognitive Science, Faculty of Medical, Health & Human Sciences, Macquarie University, Sydney, Australia; Perception in Action Research Centre, Faculty of Medical, Health & Human Sciences, Macquarie University, Sydney, Australia; Centre for Elite Performance, Training & Expertise, Macquarie University, Sydney, Australia
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19
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Awareness of voluntary action, rather than body ownership, improves motor control. Sci Rep 2021; 11:418. [PMID: 33432104 PMCID: PMC7801649 DOI: 10.1038/s41598-020-79910-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 12/15/2020] [Indexed: 01/02/2023] Open
Abstract
Awareness of the body is essential for accurate motor control. However, how this awareness influences motor control is poorly understood. The awareness of the body includes awareness of visible body parts as one’s own (sense of body ownership) and awareness of voluntary actions over that visible body part (sense of agency). Here, I show that sense of agency over a visible hand improves the initiation of movement, regardless of sense of body ownership. The present study combined the moving rubber hand illusion, which allows experimental manipulation of agency and body ownership, and the finger-tracking paradigm, which allows behavioral quantification of motor control by the ability to coordinate eye with hand movements. This eye–hand coordination requires awareness of the hand to track the hand with the eye. I found that eye–hand coordination is improved when participants experience a sense of agency over a tracked artificial hand, regardless of their sense of body ownership. This improvement was selective for the initiation, but not maintenance, of eye–hand coordination. These results reveal that the prospective experience of explicit sense of agency improves motor control, suggesting that artificial manipulation of prospective agency may be beneficial to rehabilitation and sports training techniques.
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20
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Macpherson MC, Bîrlӑdeanu A, Miles LK. Examining the relationship between subclinical levels of social anxiety and the rubber hand illusion. Acta Psychol (Amst) 2021; 212:103209. [PMID: 33197642 DOI: 10.1016/j.actpsy.2020.103209] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 09/24/2020] [Accepted: 10/26/2020] [Indexed: 02/05/2023] Open
Abstract
An embodied sense of self allows individuals to acquire moment-to-moment insight regarding the relationship between themselves and their environment. Fundamental to this experience is information regarding body ownership and self-location, which can inform both intrapersonal and interpersonal functioning. Although it is well documented that variation in mental health symptoms can impact the accuracy of bodily self-perception, little research has, to date, explored the influence of social anxiety on the embodied self. To address this issue, here we propose to examine the impact of social anxiety on the rubber hand illusion (RHI), a procedure which can distort perceptions of body location and ownership. Related literature points to competing predictions relative to how symptoms of social anxiety potentially impact susceptibility to the RHI. In the current manuscript we present the results of a pilot study indicating a positive relationship between the strength of the RHI and social anxiety, and detail a proposed registered report that seeks to replicate and extend this experiment.
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Affiliation(s)
- M C Macpherson
- School of Psychological Science, University of Western Australia, Australia.
| | - A Bîrlӑdeanu
- School of Computing Science, University of Glasgow, United Kingdom
| | - L K Miles
- School of Psychological Science, University of Western Australia, Australia
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21
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Lee HS, Griffith T, Park S. Bodily Self-Disturbances in Schizophrenia: A Comparative Study of South Korea and the USA. Psychopathology 2021; 54:262-274. [PMID: 34380136 DOI: 10.1159/000517933] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 06/17/2021] [Indexed: 11/19/2022]
Abstract
BACKGROUND Bodily self-disturbances are highly salient to the phenomenology of schizophrenia (SZ) but difficult to quantify owing to the subjective nature of these experiences that challenge verbal descriptions. The Benson et al. [PsyCh J. 2019 Mar;8(1):110-21] Body Disturbances Inventory (B-BODI) provides visual aids to help participants access the frequency, distressfulness, and vividness of subjective self-experiences with good reliability and validity in North American samples. However, the concept of the self and, accordingly, the conceptualization of self-disorders are influenced by culture. Therefore, we examined self-disturbances in individuals with SZ and control (CO) participants in 2 distinct cultures. METHODS B-BODI was administered to South Korean and North American participants, with and without SZ. Severity of symptoms in diagnosed individuals with SZ and schizotypy in CO was assessed. We also assessed perceived social isolation and mood in all participants. RESULTS Endorsement and frequency of bodily self-disturbances in SZ were similar in both cultures. In contrast, there were significant cultural differences in the degree of distress and vividness of self-disturbances. Bodily self-disturbances were experienced as more vivid and distressing to Americans than Koreans, regardless of diagnosis. For both cultures, B-BODI scores were associated with positive, but not negative, symptoms in SZ. For CO, elevated schizotypy was associated with B-BODI scores. Mood and loneliness were not associated with B-BODI scores. CONCLUSION SZ reported overall increased levels of bodily self-disturbances compared with CO, regardless of culture. However, there were cultural differences in one's emotional reaction to these experiences. Americans were more distressed by self-disturbances and experienced them more vividly than Koreans. These findings suggest that Americans may be less accepting of anomalous bodily self-experiences relative to Koreans. Last, B-BODI appears to be a useful tool for future cross-cultural studies of SZ phenomenology.
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Affiliation(s)
- Hyeon-Seung Lee
- Department of Psychology, Vanderbilt University, Nashville, Tennessee, USA
| | - Taylor Griffith
- Department of Psychology, Vanderbilt University, Nashville, Tennessee, USA
| | - Sohee Park
- Department of Psychology, Vanderbilt University, Nashville, Tennessee, USA
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22
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Chancel M, Ehrsson HH. Which hand is mine? Discriminating body ownership perception in a two-alternative forced-choice task. Atten Percept Psychophys 2020; 82:4058-4083. [PMID: 32856222 PMCID: PMC7593318 DOI: 10.3758/s13414-020-02107-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The experience of one's body as one's own is referred to as the sense of body ownership. This central part of human conscious experience determines the boundary between the self and the external environment, a crucial distinction in perception, action, and cognition. Although body ownership is known to involve the integration of signals from multiple sensory modalities, including vision, touch, and proprioception, little is known about the principles that determine this integration process, and the relationship between body ownership and perception is unclear. These uncertainties stem from the lack of a sensitive and rigorous method to quantify body ownership. Here, we describe a two-alternative forced-choice discrimination task that allows precise and direct measurement of body ownership as participants decide which of two rubber hands feels more like their own in a version of the rubber hand illusion. In two experiments, we show that the temporal and spatial congruence principles of multisensory stimulation, which determine ownership discrimination, impose tighter constraints than previously thought and that texture congruence constitutes an additional principle; these findings are compatible with theoretical models of multisensory integration. Taken together, our results suggest that body ownership constitutes a genuine perceptual multisensory phenomenon that can be quantified with psychophysics in discrimination experiments.
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Affiliation(s)
- Marie Chancel
- Department of Neuroscience, Brain, Body and Self Laboratory, Karolinska Institute, SE-171 77, Stockholm, Sweden.
| | - H Henrik Ehrsson
- Department of Neuroscience, Brain, Body and Self Laboratory, Karolinska Institute, SE-171 77, Stockholm, Sweden
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23
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Muller AM, Dalal TC, Stevenson RA. Schizotypal traits are not related to multisensory integration or audiovisual speech perception. Conscious Cogn 2020; 86:103030. [PMID: 33120291 DOI: 10.1016/j.concog.2020.103030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 09/02/2020] [Accepted: 10/04/2020] [Indexed: 12/01/2022]
Abstract
Multisensory integration, the binding of sensory information from different sensory modalities, may contribute to perceptual symptomatology in schizophrenia, including hallucinations and aberrant speech perception. Differences in multisensory integration and temporal processing, an important component of multisensory integration, are consistently found in schizophrenia. Evidence is emerging that these differences extend across the schizophrenia spectrum, including individuals in the general population with higher schizotypal traits. In the current study, we investigated the relationship between schizotypal traits and perceptual functioning, using audiovisual speech-in-noise, McGurk, and ternary synchrony judgment tasks. We measured schizotypal traits using the Schizotypal Personality Questionnaire (SPQ), hypothesizing that higher scores on Unusual Perceptual Experiences and Odd Speech subscales would be associated with decreased multisensory integration, increased susceptibility to distracting auditory speech, and less precise temporal processing. Surprisingly, these measures were not associated with the predicted subscales, suggesting that these perceptual differences may not be present across the schizophrenia spectrum.
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Affiliation(s)
- Anne-Marie Muller
- Department of Psychology, University of Western Ontario, London, ON, Canada; Brain and Mind Institute, University of Western Ontario, London, ON, Canada
| | - Tyler C Dalal
- Department of Psychology, University of Western Ontario, London, ON, Canada; Brain and Mind Institute, University of Western Ontario, London, ON, Canada
| | - Ryan A Stevenson
- Department of Psychology, University of Western Ontario, London, ON, Canada; Brain and Mind Institute, University of Western Ontario, London, ON, Canada.
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24
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Crivelli D, Balconi M. Extending the Body Ownership to Affective Experience of an Embodied Artificial Hand: a Power Spectra Investigation. Multisens Res 2020; 34:441-453. [PMID: 33706268 DOI: 10.1163/22134808-bja10037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 08/13/2020] [Indexed: 11/19/2022]
Abstract
According to implicit accounts, human self-awareness grounds on the so-called sense of ownership (SoO). Empirical investigations of SoO have mostly focused on the manipulation of self-ascription of sensations and experiences involving the body via the induction of bodily illusions, such as the Rubber-Hand Illusion (RHI). While it has been proposed that the affective dimension necessarily contributes to the development of a full ownership ascription, the relationship between affective experience and body ownership still presents many open questions. This study thus aimed at investigating the boundaries of ownership ascriptions and the extent to which an external object can be incorporated within one's own body representation, with a specific focus on the possibility for it to become a potential object of own affective experience marked by specific electrophysiological responses. Therefore, we induced RHI in 16 participants and then applied an aversive vs. pleasant stimulation to the embodied external object, while monitoring their electrophysiological activity for central physiological markers of affective processing. Data analysis revealed the effect of the stimulation condition on alpha band power over frontal areas, with higher alpha power during the pleasant stimulation condition with respect to the aversive stimulation one over medial and right frontal electrode sites. The present findings add to the limited pieces of evidence concerning the link between experiences of illusory body ownership, embodiment mechanisms, and affective factors, suggesting that the boundaries of body ownership might be extended to making incorporated objects the source of complex emotional responses beyond basic defensive reactions.
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Affiliation(s)
- Davide Crivelli
- Research Unit in Affective and Social Neuroscience, Catholic University of the Sacred Heart, Largo Gemelli 1, 20123 Milan, Italy.,Department of Psychology, Catholic University of the Sacred Heart, Largo Gemelli 1, 20123 Milan, Italy
| | - Michela Balconi
- Research Unit in Affective and Social Neuroscience, Catholic University of the Sacred Heart, Largo Gemelli 1, 20123 Milan, Italy.,Department of Psychology, Catholic University of the Sacred Heart, Largo Gemelli 1, 20123 Milan, Italy
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25
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Lev-Ari L, Hirschmann S, Dyskin O, Goldman O, Hirschmann I. The Rubber Hand Illusion Paradigm as a Sensory Learning Process in Patients with Schizophrenia. Eur Psychiatry 2020; 30:868-73. [DOI: 10.1016/j.eurpsy.2015.06.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 06/27/2015] [Accepted: 06/28/2015] [Indexed: 11/30/2022] Open
Abstract
AbstractObjective:The Rubber Hand Illusion (RHI) has previously been used to depict the hierarchy between visual, tactile and perceptual stimuli. Studies on schizophrenia inpatients (SZs) have found mixed results in the ability to first learn the illusion, and have yet to explain the learning process involved. This study's aim was two-fold: to examine the learning process of the RHI in SZs and healthy controls over time, and to better understand the relationship between psychotic symptoms and the RHI.Method:Thirty schizophrenia inpatients and 30 healthy controls underwent five different trials of the RHI over a two-week period.Results:As has been found in previous studies, SZs felt the initial illusion faster than healthy controls did, but their learning process throughout the trials was inconsistent. Furthermore, for SZs, no correlations between psychotic symptoms and the learning of the illusion emerged.Conclusion:Healthy individuals show a delayed reaction to first feeling the illusion (due to latent inhibition), but easily learn the illusion over time. For SZs, both strength of the illusion and the ability to learn the illusion over time are inconsistent. The cognitive impairment in SZ impedes the learning process of the RHI, and SZs are unable to utilize the repetition of the process as healthy individuals can.
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Effects of Human Synchronous Hand Movements in Eliciting a Sense of Agency and Ownership. Sci Rep 2020; 10:2038. [PMID: 32029854 PMCID: PMC7005016 DOI: 10.1038/s41598-020-59014-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Accepted: 01/23/2020] [Indexed: 11/21/2022] Open
Abstract
The self is built as an entity independent from the external world using the human ability to experience the senses of agency and ownership. Humans usually experience these senses during movement. Nevertheless, researchers recently reported that another person’s synchronous mirror-symmetrical movements elicited both agency and ownership in research participants. However, it is unclear whether this elicitation was caused by the synchronicity or the mirror symmetry of the movements. To address this question, we investigated the effect of interpersonal synchronization on the self-reported sense of agency and ownership in two conditions, using movements with and without mirror symmetry. Participants performed rhythmic hand movements while viewing the experimenter’s synchronous or random hand movements, and then reported their perceptions of agency and ownership in a questionnaire. We observed that agency and ownership were significantly elicited by the experimenter’s synchronous hand movements in both conditions. The results suggested that the synchronous movements of another person—rather than mirror- or non-mirror-symmetrical movements—appear to elicit the experience of a sense of agency and ownership. The results also suggested that people could experience these senses not only from their own movements but also from another person’s synchronous movements.
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Burin D, Pignolo C, Ales F, Giromini L, Pyasik M, Ghirardello D, Zennaro A, Angilletta M, Castellino L, Pia L. Relationships Between Personality Features and the Rubber Hand Illusion: An Exploratory Study. Front Psychol 2019; 10:2762. [PMID: 31920815 PMCID: PMC6914866 DOI: 10.3389/fpsyg.2019.02762] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Accepted: 11/25/2019] [Indexed: 01/31/2023] Open
Abstract
The rubber hand illusion paradigm allows investigating human body ownership by inducing an illusion of owning a life-sized fake hand. Despite the wide consensus on the fact that integration of multisensory signals is the main interpretative framework of the rubber hand illusion, increasing amount of data show that additional factors might contribute to the emergence of the illusion and, in turn, explain the strong inter-individual differences of the illusory patterns. Here, we explored whether and how personality features contribute to the emergence of the illusion by administering to healthy participants the rubber hand illusion paradigm along with two well-known personality tests, i.e., the Personality Assessment Inventory (PAI) and the Rorschach test. Results showed that two Rorschach domains (i.e., "Perception and Thinking Problems" and "Self and Other Representation") were positively correlated with the illusory mislocalization of the own left hand toward the fake hand. Further analyses suggested that while the tendency to perceive unconventionally is related to mislocalizing the own hand toward the fake hand, the association of the RHI index and other personality features measured by the Rorschach remain uncertain. However, our findings in general suggest that personality features might have a role in the emergence of the rubber hand illusion. This, in turn, could explain the high inter-individual variability of the illusory effects.
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Affiliation(s)
- Dalila Burin
- Kawashima Laboratory, Institute of Development, Aging and Cancer and Smart-Aging Research Center, Tohoku University, Sendai, Japan
| | | | - Francesca Ales
- Department of Psychology, University of Turin, Turin, Italy
| | | | - Maria Pyasik
- SpAtial, Motor and Bodily Awareness Research Group, Department of Psychology, University of Turin, Turin, Italy
| | | | | | | | | | - Lorenzo Pia
- SpAtial, Motor and Bodily Awareness Research Group, Department of Psychology, University of Turin, Turin, Italy
- Neuroscience Institute of Turin, Turin, Italy
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Crespi B, Dinsdale N. Autism and psychosis as diametrical disorders of embodiment. Evol Med Public Health 2019; 2019:121-138. [PMID: 31402979 PMCID: PMC6682708 DOI: 10.1093/emph/eoz021] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 07/11/2019] [Indexed: 12/12/2022] Open
Abstract
Humans have evolved an elaborate system of self-consciousness, self-identity, self-agency, and self-embodiment that is grounded in specific neurological structures including an expanded insula. Instantiation of the bodily self has been most-extensively studied via the 'rubber hand illusion', whereby parallel stimulation of a hidden true hand, and a viewed false hand, leads to the felt belief that the false hand is one's own. Autism and schizophrenia have both long been regarded as conditions centrally involving altered development of the self, but they have yet to be compared directly with regard to the self and embodiment. Here, we synthesize the embodied cognition literature for these and related conditions, and describe evidence that these two sets of disorders exhibit opposite susceptibilities from typical individuals to the rubber hand illusion: reduced on the autism spectrum and increased in schizophrenia and other psychotic-affective conditions. Moreover, the opposite illusion effects are mediated by a consilient set of associated phenomena, including empathy, interoception, anorexia risk and phenotypes, and patterns of genetic correlation. Taken together, these findings: (i) support the diametric model of autism and psychotic-affective disorders, (ii) implicate the adaptive human system of self-embodiment, and its neural bases, in neurodevelopmental disorders, and suggest new therapies and (iii) experimentally ground Bayesian predictive coding models with regard to autism compared with psychosis. Lay summary: Humans have evolved a highly developed sense of self and perception of one's own body. The 'rubber hand illusion' can be used to test individual variation in sense of self, relative to connection with others. We show that this illusion is reduced in autism spectrum disorders, and increased in psychotic and mood disorders. These findings have important implications for understanding and treatment of mental disorders.
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Affiliation(s)
- Bernard Crespi
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada
| | - Natalie Dinsdale
- Department of Biological Sciences, Simon Fraser University, 8888 University Drive, Burnaby, BC, Canada
- Department of Psychology, University of Saskatchewan, Saskatoon, SK, Canada
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Increased plasticity of bodily self-experience in individuals who may carry latent liability for schizophrenia. Schizophr Res 2019; 207:58-62. [PMID: 29793817 DOI: 10.1016/j.schres.2018.05.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 05/02/2018] [Accepted: 05/06/2018] [Indexed: 11/21/2022]
Abstract
Self-disturbances such as altered perception of one's own body boundary are central to the lived-in experience of schizophrenia. Bodily self-disturbances are also prevalent in healthy individuals who may carry latent liability for schizophrenia. Much of the research on self-disturbances rely on clinical interviews but these experiences are often difficult to verbalize, conceptualize and quantify. Furthermore, experimental evidence for plasticity of bodily self-experience in the schizophrenia-spectrum is scarce. We sought to quantify body boundary experience in healthy young adults who might be at an increased risk for schizophrenia with a multisensory paradigm known as the Pinocchio Illusion (PI) task that engenders the feeling that one's nose is changing, and has previously been used to demonstrate increased plasticity of bodily self-boundary in schizophrenia. 62 college students participated in the PI task that assessed bodily self-disturbances, and a tactile discrimination task. We administered the Prodromal Questionnaire Brief (PQ-B) and the Schizotypal Personality Questionnaire (SPQ) to assess latent liability for schizophrenia. We found that PI was enhanced in individuals with elevated PQ-B scores but their tactile sensitivity was intact. PI was associated with the positive syndrome of schizotypy, but not with negative or disorganized factors. Increased PQ-B and SPQ scores were associated with loneliness. To conclude, these results highlight the importance of bodily self-disturbances in the broader context of the schizophrenia spectrum.
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Prikken M, van der Weiden A, Baalbergen H, Hillegers MH, Kahn RS, Aarts H, van Haren NE. Multisensory integration underlying body-ownership experiences in schizophrenia and offspring of patients: a study using the rubber hand illusion paradigm. J Psychiatry Neurosci 2019; 44:177-184. [PMID: 30525317 PMCID: PMC6488483 DOI: 10.1503/jpn.180049] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Schizophrenia is a disorder of basic self-disturbance. Evidence suggests that people with schizophrenia may have aberrant experiences of body ownership: they may feel that they are not the subject of their own body experiences. However, little is known about the development of such disturbances. METHODS Using a rubber hand illusion paradigm, we assessed body ownership in patients with schizophrenia (n = 54), healthy controls (n = 56), children/adolescents at increased familial risk of developing schizophrenia (n = 24) or mood disorders (n = 33), and children/adolescents without this risk (n = 18). In this paradigm, a rubber hand (visible) and a participant’s real hand (invisible) were stroked synchronously and asynchronously; we then measured subjective illusory experiences and proprioceptive drift. RESULTS All groups showed the expected effect of the rubber hand illusion: stronger proprioceptive drift and increased subjective illusory experiences after synchronous versus asynchronous stroking. The effect of synchronicity on subjective experiences was significantly weaker in patients with schizophrenia than in healthy controls, and subjective ratings were positively correlated with delusions in patients. We found no significant differences between children/adolescents with and without increased familial risk. LIMITATIONS Large individual differences raised questions for future research. CONCLUSION We found subtle disturbances in body-ownership experiences in patients with schizophrenia, which were associated with delusions. We found no evidence for impairments in children/adolescents at increased familial risk of developing schizophrenia or a mood disorder. Longitudinal data might reveal whether impairments in body ownership are predictive of psychosis onset.
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Affiliation(s)
- Merel Prikken
- From the Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Utrecht, the Netherlands (Prikken, Baalbergen, Hillegers, Kahn, Van Haren); the Utrecht University, Department of Psychology, Utrecht, the Netherlands (Van der Weiden, Aarts); the Department of Child and Adolescent Psychiatry/Psychology, Sophia Children’s Hospital, Erasmus Medical Centre, Rotterdam, the Netherlands (Hillegers); and the Icahn School of Medicine at Mount Sinai, Department of Psychiatry, New York, NY (Kahn)
| | - Anouk van der Weiden
- From the Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Utrecht, the Netherlands (Prikken, Baalbergen, Hillegers, Kahn, Van Haren); the Utrecht University, Department of Psychology, Utrecht, the Netherlands (Van der Weiden, Aarts); the Department of Child and Adolescent Psychiatry/Psychology, Sophia Children’s Hospital, Erasmus Medical Centre, Rotterdam, the Netherlands (Hillegers); and the Icahn School of Medicine at Mount Sinai, Department of Psychiatry, New York, NY (Kahn)
| | - Heleen Baalbergen
- From the Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Utrecht, the Netherlands (Prikken, Baalbergen, Hillegers, Kahn, Van Haren); the Utrecht University, Department of Psychology, Utrecht, the Netherlands (Van der Weiden, Aarts); the Department of Child and Adolescent Psychiatry/Psychology, Sophia Children’s Hospital, Erasmus Medical Centre, Rotterdam, the Netherlands (Hillegers); and the Icahn School of Medicine at Mount Sinai, Department of Psychiatry, New York, NY (Kahn)
| | - Manon H.J. Hillegers
- From the Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Utrecht, the Netherlands (Prikken, Baalbergen, Hillegers, Kahn, Van Haren); the Utrecht University, Department of Psychology, Utrecht, the Netherlands (Van der Weiden, Aarts); the Department of Child and Adolescent Psychiatry/Psychology, Sophia Children’s Hospital, Erasmus Medical Centre, Rotterdam, the Netherlands (Hillegers); and the Icahn School of Medicine at Mount Sinai, Department of Psychiatry, New York, NY (Kahn)
| | - René S. Kahn
- From the Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Utrecht, the Netherlands (Prikken, Baalbergen, Hillegers, Kahn, Van Haren); the Utrecht University, Department of Psychology, Utrecht, the Netherlands (Van der Weiden, Aarts); the Department of Child and Adolescent Psychiatry/Psychology, Sophia Children’s Hospital, Erasmus Medical Centre, Rotterdam, the Netherlands (Hillegers); and the Icahn School of Medicine at Mount Sinai, Department of Psychiatry, New York, NY (Kahn)
| | - Henk Aarts
- From the Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Utrecht, the Netherlands (Prikken, Baalbergen, Hillegers, Kahn, Van Haren); the Utrecht University, Department of Psychology, Utrecht, the Netherlands (Van der Weiden, Aarts); the Department of Child and Adolescent Psychiatry/Psychology, Sophia Children’s Hospital, Erasmus Medical Centre, Rotterdam, the Netherlands (Hillegers); and the Icahn School of Medicine at Mount Sinai, Department of Psychiatry, New York, NY (Kahn)
| | - Neeltje E.M. van Haren
- From the Brain Centre Rudolf Magnus, University Medical Centre Utrecht, Utrecht, the Netherlands (Prikken, Baalbergen, Hillegers, Kahn, Van Haren); the Utrecht University, Department of Psychology, Utrecht, the Netherlands (Van der Weiden, Aarts); the Department of Child and Adolescent Psychiatry/Psychology, Sophia Children’s Hospital, Erasmus Medical Centre, Rotterdam, the Netherlands (Hillegers); and the Icahn School of Medicine at Mount Sinai, Department of Psychiatry, New York, NY (Kahn)
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Pienkos E, Giersch A, Hansen M, Humpston C, McCarthy-Jones S, Mishara A, Nelson B, Park S, Raballo A, Sharma R, Thomas N, Rosen C. Hallucinations Beyond Voices: A Conceptual Review of the Phenomenology of Altered Perception in Psychosis. Schizophr Bull 2019; 45:S67-S77. [PMID: 30715544 PMCID: PMC6357976 DOI: 10.1093/schbul/sby057] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Recent psychiatric research and treatment initiatives have tended to move away from traditional diagnostic categories and have focused instead on transdiagnostic phenomena, such as hallucinations. However, this emphasis on isolated experiences may artificially limit the definition of such phenomena and ignore the rich, complex, and dynamic changes occurring simultaneously in other domains of experience. This article reviews the literature on a range of experiential features associated with psychosis, with a focus on their relevance for hallucinations. Phenomenological research on changes in cognition, perception, selfhood and reality, temporality, interpersonal experience, and embodiment are discussed, along with their implications for traditional conceptualizations of hallucinations. We then discuss several phenomenological and neurocognitive theories, as well as the potential impact of trauma on these phenomena. Hallucinations are suggested to be an equifinal outcome of multiple genetic, neurocognitive, subjective, and social processes; by grouping them together under a single, operationalizable definition, meaningful differences in etiology and phenomenology may be ignored. It is suggested that future research efforts strive to incorporate a broader range of experiential alterations, potentially expanding on traditional definitions of hallucinations. Relevance for clinical practice, including emphasizing phenomenologically responsive techniques and developing targeted new therapies, is discussed.
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Affiliation(s)
- Elizabeth Pienkos
- Graduate Institute of Professional Psychology, University of Hartford, West Hartford, CT
| | - Anne Giersch
- INSERM U1114, Pôle de Psychiatrie, Fédération de Médecine Translationnelle de Strasbourg (FMTS), Centre Hospitalier Régional Universitaire of Strasbourg, Université de Strasbourg, Strasbourg, France
| | - Marie Hansen
- Department of Clinical Psychology, Long Island University Brooklyn, Brooklyn, NY
| | - Clara Humpston
- Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | | | - Aaron Mishara
- Clinical Psychology Department, The Chicago School of Professional Psychology, Los Angeles, CA
| | - Barnaby Nelson
- Orygen, The National Centre of Excellence in Youth Mental Health, Parkville, Victoria, Australia
- Centre for Youth Mental Health, The University of Melbourne, Parkville, Australia
| | - Sohee Park
- Department of Psychology, Vanderbilt University, Nashville, TN
- Kyung Hee University, Seoul, Korea
| | - Andrea Raballo
- Department of Psychology, Psychopathology and Development Research Unit, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
- Department of Medicine, Division of Psychiatry, Clinical Psychology and Rehabilitation, University of Perugia, Perugia, Italy
| | - Rajiv Sharma
- Department of Psychiatry, University of Illinois at Chicago, Chicago, IL
- Jesse Brown Veterans Affairs Medical Center, Chicago, IL
| | - Neil Thomas
- Centre for Mental Health, Swinburne University of Technology, Hawthorn, Victoria, Australia
| | - Cherise Rosen
- Department of Psychiatry, University of Illinois at Chicago, Chicago, IL
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Weakening of the Sense of Body Ownership in Schizophrenia: Implications for the Psychological Mechanism of Anxiety Reduction. CURRENT PSYCHOLOGY 2019. [DOI: 10.1007/s12144-017-9593-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Xu A, Cullen B, Penner C, Zimmerman C, Kerr C, Schmalzl L. Comparing embodiment experiences in expert meditators and non-meditators using the rubber hand illusion. Conscious Cogn 2018; 65:325-333. [DOI: 10.1016/j.concog.2018.09.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 08/24/2018] [Accepted: 09/03/2018] [Indexed: 10/28/2022]
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Shaqiri A, Roinishvili M, Kaliuzhna M, Favrod O, Chkonia E, Herzog MH, Blanke O, Salomon R. Rethinking Body Ownership in Schizophrenia: Experimental and Meta-analytical Approaches Show no Evidence for Deficits. Schizophr Bull 2018; 44:643-652. [PMID: 29036731 PMCID: PMC5890460 DOI: 10.1093/schbul/sbx098] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Schizophrenia is a severe psychiatric disorder, in which patients experience an abnormal sense of self. While deficits in sensorimotor self-representation (agency) are well documented in schizophrenia, less is known about other aspects of bodily self-representation (body ownership). Here, we tested a large cohort (N = 59) of chronic schizophrenia patients and matched controls (N = 30) on a well-established body illusion paradigm, the Full Body Illusion (FBI). In this paradigm, changes in body ownership are induced through prolonged multisensory stimulation, in which participants are stroked on their back while seeing the stroking on the back of a virtual body. When the felt and seen stroking are synchronous, participants typically feel higher identification with the seen body as well as a drift in self-location towards it. However, when the stroking is asynchronous, no such changes occur. Our results show no evidence for abnormal body ownership in schizophrenia patients. A meta-analysis of previous work corroborates this result. Thus, while schizophrenia patients may be impaired in the sense of agency, their multisensory bodily self-representation, as tested here, seems to be unaffected by the illness.
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Affiliation(s)
- Albulena Shaqiri
- Laboratory of Psychophysics, Brain Mind Institute, EPFL, Lausanne, Switzerland
| | - Maya Roinishvili
- Vision Research Laboratory, Beritashvili Centre of Experimental Biomedicine, Tbilisi, Georgia
- Institute of Cognitive Neurosciences, Agricultural University of Georgia, Tbilisi, Georgia
| | - Mariia Kaliuzhna
- Laboratory of Cognitive Neuroscience, Brain Mind Institute, EPFL, Lausanne, Switzerland
- Chair in Cognitive Neuroprosthetics, Center for Neuroprosthetics, School of Life Science, EPFL, Geneva, Switzerland
- Department of Cognitive Science, Macquarie University, Sydney, Australia
| | - Ophélie Favrod
- Laboratory of Psychophysics, Brain Mind Institute, EPFL, Lausanne, Switzerland
| | - Eka Chkonia
- Institute of Cognitive Neurosciences, Agricultural University of Georgia, Tbilisi, Georgia
- Department of Psychiatry, Tbilisi State Medical University, Tbilisi, Georgia
| | - Michael H Herzog
- Laboratory of Psychophysics, Brain Mind Institute, EPFL, Lausanne, Switzerland
| | - Olaf Blanke
- Laboratory of Cognitive Neuroscience, Brain Mind Institute, EPFL, Lausanne, Switzerland
- Chair in Cognitive Neuroprosthetics, Center for Neuroprosthetics, School of Life Science, EPFL, Geneva, Switzerland
| | - Roy Salomon
- Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat Gan, Israel
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Dauphin J. Differentiation Between Schizophreniform Configurations and Psychotic Personality Structures. Psychodyn Psychiatry 2018; 45:187-215. [PMID: 28590204 DOI: 10.1521/pdps.2017.45.2.187] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The symptom overlap between primary psychotic and severe personality disorders renders timely diagnosis challenging, which often results in ambiguous treatment and poorly defined outcomes. Kernberg's (1984) structural model of personality, treating symptoms as a non-pathognomonic higher order construct, has much contributed to our understanding of the nature of some severe disorders, highlighting fundamental facets of personality function. However, the model's main focus is on borderline personality organization and thus offers an incomplete formulation of psychotic structure. With regard to the psychotic structure, two distinct pathological disorders are currently confounded and need to be distinguished: (1) the authentic psychotic structures, mainly resulting from failures in early relational and affective development, and (2) schizophreniform configurations, mostly derived from a neurodevelopmental etiology. This differentiation, while specifying the notion of psychotic personality structure, takes into consideration: (a) the role of temperament bias, hypersensitity in particular; (b) dissimilar productions in response to projective testing, such as the Rorschach inkblot test; (c) differential processes in response to psychotherapy, including typical transferential manifestations; (d) differential symptom presentation. Key criteria to facilitate the differential diagnosis with severely regressed borderline structures are suggested. Clinical material illustrates the application of the proposed revised model. Therapeutic implications are discussed.
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Affiliation(s)
- Julie Dauphin
- Institut universitaire en santé mentale de Montréal (Programme des troubles psychotiques), Montréal (Québec), Canada
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36
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Botan V, Fan S, Critchley H, Ward J. Atypical susceptibility to the rubber hand illusion linked to sensory-localised vicarious pain perception. Conscious Cogn 2018. [PMID: 29529588 DOI: 10.1016/j.concog.2018.02.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The Rubber Hand Illusion (RHI) paradigm has been widely used to investigate the sense of body ownership. People who report experiencing the pain of others are hypothesised to have differences in computing body ownership and, hence, we predicted that they would perform atypically on the RHI. The Vicarious Pain Questionnaire (VPQ), was used to divide participants into three groups: (1) non-responders (people who report no pain when seeing someone else experiencing physical pain), (2) sensory-localised responders (report sensory qualities and a localised feeling of pain) and (3) affective-general responders (report a generalised and emotional feeling of pain). The sensory-localised group, showed susceptibility to the RHI (increased proprioceptive drift) irrespective of whether stimulation was synchronous or asynchronous, whereas the other groups only showed the RHI in the synchronous condition. This is not a general bias to always incorporate the dummy hand as we did not find increased susceptibility in other conditions (seeing touch without feeling touch, or feeling touch without seeing touch), but there was a trend for this group to incorporate the dummy hand when it was stroked with a laser light. Although individual differences in the RHI have been noted previously, this particular pattern is rare. It suggests a greater malleability (i.e. insensitivity to asynchrony) in the conditions in which other bodies influence own-body judgments.
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Affiliation(s)
- V Botan
- School of Psychology, University of Sussex, UK; Sackler Centre for Consciousness Science, UK.
| | - S Fan
- School of Psychology, University of Sussex, UK
| | - H Critchley
- School of Psychology, University of Sussex, UK; Sackler Centre for Consciousness Science, UK; Brighton and Sussex Medical School, UK
| | - J Ward
- School of Psychology, University of Sussex, UK; Sackler Centre for Consciousness Science, UK
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Graham-Schmidt KT, Martin-Iverson MT, Waters FAV. Self- and other-agency in people with passivity (first rank) symptoms in schizophrenia. Schizophr Res 2018; 192:75-81. [PMID: 28416095 DOI: 10.1016/j.schres.2017.04.024] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 04/10/2017] [Accepted: 04/11/2017] [Indexed: 10/19/2022]
Abstract
Individuals with passivity (first-rank) symptoms report that their actions, thoughts and sensations are influenced or controlled by an external (non-self) agent. Passivity symptoms are closely linked to schizophrenia and related disorders yet they remain poorly understood. One dominant framework posits a role for deficits in the sense of agency. An important question is whether deficits in self-agency can be differentiated from other-agency in schizophrenia and passivity symptoms. This study aimed to evaluate self- and other-agency in 51 people with schizophrenia (n=20 current, 10 past, 21 no history of passivity symptoms), and 48 healthy controls. Participants completed the projected hand illusion (PHI) with active and passive movements, as well as immediate and delayed visual feedback. Experiences of agency and loss of agency over the participant's hand and the image ('the other hand') were assessed with a self-report questionnaire. Those with passivity symptoms (current and past) reported less difference in agency between active and passive movements on items assessing agency over their own hand (but not agency over the other hand). Relative to the healthy controls, the current and never groups continued to experience the illusion with delayed visual feedback suggesting impaired timing mechanisms regardless of symptom profile. These findings are consistent with a reduced contribution of proprioceptive predictive cues to agency judgements specific to self representations in people with passivity symptoms, and a subsequent reliance on external visual cues in these judgements. Altogether, these findings emphasise the multifactorial nature of agency and the contribution of multiple impairments to passivity symptoms.
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Affiliation(s)
- Kyran T Graham-Schmidt
- School of Medicine and Pharmacology, Faculty of Medicine, Dentistry and Health Sciences, The University of Western Australia, Perth, Australia.
| | - Mathew T Martin-Iverson
- School of Medicine and Pharmacology, Faculty of Medicine, Dentistry and Health Sciences, The University of Western Australia, Perth, Australia
| | - Flavie A V Waters
- School of Psychiatry and Clinical Neurosciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Western Australia, Perth, Australia; Clinical Research Centre, Graylands Health Campus, North Metropolitan Health Services - Mental Health, Perth, Australia
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38
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Chen W, Zhang J, Qian Y, Gao Q. How disentangled sense of agency and sense of ownership can interact with different emotional events on stress feelings. PSICOLOGIA-REFLEXAO E CRITICA 2017; 30:17. [PMID: 32026071 PMCID: PMC6974349 DOI: 10.1186/s41155-017-0071-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 08/02/2017] [Indexed: 11/10/2022] Open
Abstract
We used the virtual hand illusion paradigm to study how sense of agency and sense of (body) ownership can interact with different emotional events on stress feelings. Converging evidence for at least the partial independence of agency and ownership was found. For instance, sense of agency was a better predictor of individual anxiety levels than sense of ownership and males showed stronger effects related to agency-presumably due to gender-specific attribution styles and empathy skills. Moreover, agency and ownership also interacted with emotional events and led to different anxiety levels. Taken together, our findings suggest that the disentangled sense of agency and sense of ownership can interact with different emotional events and influenced stress feelings more in threatening situations than awarding ones.
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Affiliation(s)
- Wei Chen
- Department of Psychology, Shaoxing University, Shaoxing, China.
| | - Jing Zhang
- Institute of Psychological Health, Hangzhou Dianzi University, Hangzhou, China.,Leiden Institute for Brain and Cognition, Leiden University, Leiden, The Netherlands
| | - Yanyan Qian
- School of Psychology, Nanjing Normal University, Nanjing, China
| | - Qiyang Gao
- Department of Psychology, Shaoxing University, Shaoxing, China
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39
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Ferri F, Nikolova YS, Perrucci MG, Costantini M, Ferretti A, Gatta V, Huang Z, Edden RAE, Yue Q, D’Aurora M, Sibille E, Stuppia L, Romani GL, Northoff G. A Neural "Tuning Curve" for Multisensory Experience and Cognitive-Perceptual Schizotypy. Schizophr Bull 2017; 43:801-813. [PMID: 28168302 PMCID: PMC5472158 DOI: 10.1093/schbul/sbw174] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Our coherent perception of external events is enabled by the integration of inputs from different senses occurring within a range of temporal offsets known as the temporal binding window (TBW), which varies from person to person. A relatively wide TBW may increase the likelihood that stimuli originating from different environmental events are erroneously integrated and abnormally large TBW has been found in psychiatric disorders characterized by unusual perceptual experiences. Despite strong evidence of inter-individual differences in TBW, both within clinical and nonclinical populations, the neurobiological underpinnings of this variability remain unclear. We adopted an integrated strategy linking TBW to temporal dynamics in functional magnetic resonance imaging (fMRI)-resting-state activity and cortical excitation/inhibition (E/I) balance. E/I balance was indexed by glutamate/Gamma-AminoButyric Acid (GABA) concentrations and common variation in glutamate and GABA genes in a healthy sample. Stronger resting-state long-range temporal correlations, indicated by larger power law exponent (PLE), in the auditory cortex, robustly predicted narrower audio-tactile TBW, which was in turn associated with lower cognitive-perceptual schizotypy. Furthermore, PLE was highest and TBW narrowest for individuals with intermediate levels of E/I balance, with shifts towards either extreme resulting in reduced multisensory temporal precision and increased schizotypy, effectively forming a neural "tuning curve" for multisensory experience and schizophrenia risk. Our findings shed light on the neurobiological underpinnings of multisensory integration and its potentially clinically relevant inter-individual variability.
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Affiliation(s)
- Francesca Ferri
- Department of Psychology, University of Essex, Colchester, UK;,Institute of Mental Health Research, Brain and Mind Research Centre, University of Ottawa, Ottawa, ON, Canada;,These authors contributed equally to the article
| | - Yuliya S. Nikolova
- Campbell Family Mental Health Research Institute of CAMH, Toronto, ON, Canada;,These authors contributed equally to the article
| | - Mauro Gianni Perrucci
- Department of Neuroscience, Imaging and Clinical Science, “G.d’Annunzio” University of Chieti, and ITAB—Institute for Advanced Biomedical Technologies, Chieti, Italy
| | - Marcello Costantini
- Department of Psychology, University of Essex, Colchester, UK;,Department of Neuroscience, Imaging and Clinical Science, “G.d’Annunzio” University of Chieti, and ITAB—Institute for Advanced Biomedical Technologies, Chieti, Italy
| | - Antonio Ferretti
- Department of Neuroscience, Imaging and Clinical Science, “G.d’Annunzio” University of Chieti, and ITAB—Institute for Advanced Biomedical Technologies, Chieti, Italy
| | - Valentina Gatta
- Department of Psychological, Humanities and Territorial Sciences, “G.d’Annunzio” University of Chieti, Chieti, Italy
| | - Zirui Huang
- Institute of Mental Health Research, Brain and Mind Research Centre, University of Ottawa, Ottawa, ON, Canada
| | - Richard A. E. Edden
- Russel H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University, Baltimore, MD;,F. M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, MD
| | - Qiang Yue
- Department of Radiology, West China Hospital of Sichuan University, Chengdu, China
| | - Marco D’Aurora
- Department of Psychological, Humanities and Territorial Sciences, “G.d’Annunzio” University of Chieti, Chieti, Italy
| | - Etienne Sibille
- Campbell Family Mental Health Research Institute of CAMH, Toronto, ON, Canada;,Departments of Psychiatry and of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
| | - Liborio Stuppia
- Department of Psychological, Humanities and Territorial Sciences, “G.d’Annunzio” University of Chieti, Chieti, Italy
| | - Gian Luca Romani
- Department of Neuroscience, Imaging and Clinical Science, “G.d’Annunzio” University of Chieti, and ITAB—Institute for Advanced Biomedical Technologies, Chieti, Italy
| | - Georg Northoff
- Institute of Mental Health Research, Brain and Mind Research Centre, University of Ottawa, Ottawa, ON, Canada
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40
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Blain SD, Peterman JS, Park S. Subtle cues missed: Impaired perception of emotion from gait in relation to schizotypy and autism spectrum traits. Schizophr Res 2017; 183:157-160. [PMID: 27838096 DOI: 10.1016/j.schres.2016.11.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 10/04/2016] [Accepted: 11/04/2016] [Indexed: 10/20/2022]
Abstract
BACKGROUND Deficits in emotion perception are central features of schizophrenia and autism spectrum disorders. These conditions are also associated with disrupted embodiment and impaired processing of biological motion. However, medication and the impact of illness over time complicate the study of socioemotional processing in such neuropsychiatric populations. Thus, the current study investigated the perception of emotional cues from gait, in relation to autistic and schizotypal traits in the general population. METHODS Self-report measures of schizotypy and autism-spectrum were obtained from 107 healthy participants. An affective biological motion task that required participants to discriminate emotions from the gait patterns of polygonal avatars at varying levels of emotional intensity was used to assess accuracy of emotion perception. RESULTS Emotion perception accuracy depended on the stimulus intensity. Those with elevated autism spectrum quotient and those with elevated positive syndrome (cognitive-perceptual) schizotypy showed deficits in emotion perception from gait. CONCLUSIONS Perception of emotion from low-intensity gait cues is compromised in those who may carry liability for autism or psychosis. Emotion perception deficits may be a core feature of autism and schizophrenia, rather than simply being a downstream consequence of illness duration or medication.
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Affiliation(s)
- Scott D Blain
- Department of Psychology, Vanderbilt University, 111, 21st Avenue South, Nashville, TN 37240, United States.
| | - Joel S Peterman
- Department of Psychology, Vanderbilt University, 111, 21st Avenue South, Nashville, TN 37240, United States.
| | - Sohee Park
- Department of Psychology, Vanderbilt University, 111, 21st Avenue South, Nashville, TN 37240, United States.
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41
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Noel JP, Cascio CJ, Wallace MT, Park S. The spatial self in schizophrenia and autism spectrum disorder. Schizophr Res 2017; 179:8-12. [PMID: 27650196 PMCID: PMC5219859 DOI: 10.1016/j.schres.2016.09.021] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 09/07/2016] [Accepted: 09/14/2016] [Indexed: 11/25/2022]
Abstract
Schizophrenia (SZ) and autism spectrum disorder (ASD) have been both described as disorders of the self. However, the manner in which the sense of self is impacted in these disorders is strikingly different. In the current review, we propose that SZ and ASD lay at opposite extremes of a particular component of the representation of self; namely, self-location and the construct of peripersonal space. We evaluate emerging literature suggesting that while SZ individuals possess an extremely weak or variable bodily boundary between self and other, ASD patients possess a sharper self-other boundary. Furthermore, based on recent behavioral and neural network modeling findings, we propose that multisensory training focused on either sharpening (for SZ) or making shallower (for ASD) the self-other boundary may hold promise as an interventional tool in the treatment of these disorders.
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Affiliation(s)
- Jean-Paul Noel
- Neuroscience Graduate Program, Vanderbilt Brain Institute, Vanderbilt University Medical Center, Vanderbilt University, Nashville, TN, USA.
| | - Carissa J Cascio
- Department of Psychiatry, Vanderbilt School of Medicine, Vanderbilt University, Nashville, TN, USA; Vanderbilt Kennedy Center, Vanderbilt University, Nashville, TN, USA
| | - Mark T Wallace
- Vanderbilt Kennedy Center, Vanderbilt University, Nashville, TN, USA; Department of Hearing and Speech, Vanderbilt School of Medicine, Vanderbilt University, Nashville, TN, USA; Department of Psychology, Vanderbilt University, Nashville, TN, USA
| | - Sohee Park
- Department of Psychiatry, Vanderbilt School of Medicine, Vanderbilt University, Nashville, TN, USA; Department of Psychology, Vanderbilt University, Nashville, TN, USA
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42
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Marotta A, Tinazzi M, Cavedini C, Zampini M, Fiorio M. Individual Differences in the Rubber Hand Illusion Are Related to Sensory Suggestibility. PLoS One 2016; 11:e0168489. [PMID: 27977783 PMCID: PMC5158054 DOI: 10.1371/journal.pone.0168489] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 11/30/2016] [Indexed: 01/28/2023] Open
Abstract
In the rubber hand illusion (RHI), watching a rubber hand being stroked in synchrony with one’s own hidden hand may induce a sense of ownership over the rubber hand. The illusion relies on bottom-up multisensory integration of visual, tactile, and proprioceptive information, and on top-down processes through which the rubber hand is incorporated into pre-existing representations of the body. Although the degree of illusory experience varies largely across individuals, the factors influencing individual differences are unknown. We investigated whether sensory suggestibility might modulate susceptibility to the RHI. Sensory suggestibility is a personality trait related to how individuals react to sensory information. Because of its sensory nature, this trait could be relevant for studies using the RHI paradigm. Seventy healthy volunteers were classified by Sensory Suggestibility Scale (SSS) scores as having high or low suggestibility and assigned to either a high- (High-SSS) or a low-suggestibility (Low-SSS) group. Two components of the RHI were evaluated in synchronous and asynchronous stroking conditions: subjective experience of sense of ownership over the rubber hand via a 9-statement questionnaire, and proprioceptive drift as measured with a ruler. The High-SSS group was generally more susceptible to the subjective component; in the synchronous condition, they rated the statement assessing the sense of ownership higher than the Low-SSS group. The scores for this statement significantly correlated with the total SSS score, indicating that the higher the sensory suggestibility, the stronger the sense of ownership. No effect of sensory suggestibility on proprioceptive drift was observed, suggesting that the effect is specific for the subjective feeling of ownership. This study demonstrates that sensory suggestibility may contribute to participants’ experience of the illusion and should be considered when using the RHI paradigm.
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Affiliation(s)
- Angela Marotta
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
- * E-mail: (MF); (AM)
| | - Michele Tinazzi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Clelia Cavedini
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Massimiliano Zampini
- Department of Psychology and Cognitive Science, University of Trento, Rovereto, Italy
- Center for Mind/Brain Sciences, University of Trento, Trento, Italy
| | - Mirta Fiorio
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
- * E-mail: (MF); (AM)
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43
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Ferri F, Ambrosini E, Costantini M. Spatiotemporal processing of somatosensory stimuli in schizotypy. Sci Rep 2016; 6:38735. [PMID: 27934937 PMCID: PMC5146666 DOI: 10.1038/srep38735] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 11/14/2016] [Indexed: 12/26/2022] Open
Abstract
Unusual interaction behaviors and perceptual aberrations, like those occurring in schizotypy and schizophrenia, may in part originate from impaired remapping of environmental stimuli in the body space. Such remapping is contributed by the integration of tactile and proprioceptive information about current body posture with other exteroceptive spatial information. Surprisingly, no study has investigated whether alterations in such remapping occur in psychosis-prone individuals. Four hundred eleven students were screened with respect to schizotypal traits using the Schizotypal Personality Questionnaire. A subgroup of them, classified as low, moderate, and high schizotypes were to perform a temporal order judgment task of tactile stimuli delivered on their hands, with both uncrossed and crossed arms. Results revealed marked differences in touch remapping in the high schizotypes as compared to low and moderate schizotypes. For the first time here we reveal that the remapping of environmental stimuli in the body space, an essential function to demarcate the boundaries between self and external world, is altered in schizotypy. Results are discussed in relation to recent models of 'self-disorders' as due to perceptual incoherence.
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Affiliation(s)
- Francesca Ferri
- Centre for Brain Science, Department of Psychology, University of Essex, Colchester, UK
| | | | - Marcello Costantini
- Centre for Brain Science, Department of Psychology, University of Essex, Colchester, UK.,Laboratory of Neuropsychology and Cognitive Neuroscience, Department of Neuroscience and Imaging, University G. d'Annunzio &Institute for Advanced Biomedical Technologies - ITAB, Foundation University G. d'Annunzio, Chieti, Italy
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44
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Michael J, Park S. Anomalous bodily experiences and perceived social isolation in schizophrenia: An extension of the Social Deafferentation Hypothesis. Schizophr Res 2016; 176:392-397. [PMID: 27344986 PMCID: PMC8070733 DOI: 10.1016/j.schres.2016.06.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 06/07/2016] [Accepted: 06/10/2016] [Indexed: 10/21/2022]
Abstract
BACKGROUND Disturbances of the bodily self are fundamental to the phenomenological experience of individuals with schizophrenia, a population at risk for social isolation. Both proprioception and exteroception contribute to a sense of consistent body boundary that contains the self across time and space, and this process is influenced by self-other (social) interactions. However, the relationship between social isolation, exteroception, and in-the-moment changes in body representation has not been elucidated. We investigated susceptibility to anomalous bodily experiences with a phantom nose induction procedure that elicits a sensation that one's nose is changing (Pinocchio Illusion: PI) in relation to exteroceptive awareness and social isolation. METHODS 25 individuals with schizophrenia (SZ) and 15 matched controls (CO) participated in a PI induction procedure to quantify susceptibility to bodily aberrations and a tactile discrimination task to assess exteroception. Clinical symptoms in SZ and schizotypy in CO were assessed, in addition to a self-report measure of perceived social isolation. RESULTS Compared to CO, SZ showed increased PI and impaired tactile discriminability. SZ reported greater loneliness than CO. PI scores were correlated with increased loneliness and decreased tactile discriminability. CONCLUSIONS Greater susceptibility to anomalous bodily experiences, together with reduced exteroceptive awareness and increased loneliness, is compatible with the framework of Hoffman's Social Deafferentation Hypothesis, which posits that a functional "amputation" from one's social environment could lead to a reorganization of the social brain network, resulting in hallucinations and delusions. These findings underscore the importance of the relationship between social isolation and self-disturbances in schizophrenia.
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Affiliation(s)
- Jamie Michael
- Department of Psychology, Vanderbilt University, 111, 21(st) Avenue South, Nashville, TN 37240, United States.
| | - Sohee Park
- Department of Psychology, Vanderbilt University, 111, 21(st) Avenue South, Nashville, TN 37240, United States.
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45
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Ardizzi M, Ambrosecchia M, Buratta L, Ferri F, Peciccia M, Donnari S, Mazzeschi C, Gallese V. Interoception and Positive Symptoms in Schizophrenia. Front Hum Neurosci 2016; 10:379. [PMID: 27512369 PMCID: PMC4961721 DOI: 10.3389/fnhum.2016.00379] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 07/13/2016] [Indexed: 11/13/2022] Open
Abstract
The present study focuses on the multifaceted concept of self-disturbance in schizophrenia, adding knowledge about a not yet investigated aspect, which is the interoceptive accuracy. Starting from the assumption that interoceptive accuracy requires an intact sense of self, which otherwise was proved to be altered in schizophrenia, the aim of the present study was to explore interoceptive accuracy in a group of schizophrenia patients, compared to healthy controls. Furthermore, the possible association between interoceptive accuracy and patients' positive and negative symptomatology was assessed. To pursue these goals, a group of 23 schizophrenia patients and a group of 23 healthy controls performed a heartbeat perception task. Patients' symptomatology was assessed by means of the Positive and Negative Syndrome Scale (PANSS). Results demonstrated significantly lower interoceptive accuracy in schizophrenia patients compared to healthy controls. This difference was not accounted for participants' age, BMI, anxiety levels, and heart rate. Furthermore, patients' illness severity, attention and pharmacological treatment did not influence their interoceptive accuracy levels. Interestingly, a strong positive relation between interoceptive accuracy and positive symptoms severity, especially Grandiosity, was found. The present results demonstrate for the first time that interoceptive accuracy is altered in schizophrenia. Furthermore, they prove a specific association between interoceptive accuracy and positive symptomatology, suggesting that the symptom Grandiosity might be protective against an altered basic sense of self in patients characterized by higher sensibility to their inner bodily sensations.
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Affiliation(s)
- Martina Ardizzi
- Department of Neuroscience, University of Parma Parma, Italy
| | | | - Livia Buratta
- Department of Human Science and Education, University of Perugia Perugia, Italy
| | - Francesca Ferri
- Department of Psychology, University of Essex Colchester, UK
| | - Maurizio Peciccia
- Department of Human Science and Education, University of Perugia Perugia, Italy
| | | | - Claudia Mazzeschi
- Department of Human Science and Education, University of Perugia Perugia, Italy
| | - Vittorio Gallese
- Department of Neuroscience, University of ParmaParma, Italy; Institute of Philosophy, School of Advanced Study, University of LondonLondon, UK
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46
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Klaver M, Dijkerman HC. Bodily Experience in Schizophrenia: Factors Underlying a Disturbed Sense of Body Ownership. Front Hum Neurosci 2016; 10:305. [PMID: 27378895 PMCID: PMC4911393 DOI: 10.3389/fnhum.2016.00305] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 06/03/2016] [Indexed: 11/24/2022] Open
Abstract
Emerging evidence is now challenging the view that patients diagnosed with schizophrenia experience a selective deficit in their sense of agency. Additional disturbances seem to exist in their sense of body ownership. However, the factors underlying this disturbance in body ownership remain elusive. Knowledge of these factors, and increased understanding of how body ownership is related to other abnormalities seen in schizophrenia, could ultimately advance development of new treatments. Research on body ownership in schizophrenia has mainly been investigated with the rubber hand illusion (RHI). Schizophrenia patients show higher susceptibility to the RHI, which may be explained by a stronger reliance on multisensory information over weaker stored body representations. This review shows that a coherent sense of body ownership arises from the integration of both bottom-up sensory processes and higher order, top-down bodily- and perceptual representations. Multisensory integration, temporal binding, anticipation, intention and efferent signals all partly modulate the complex experience of body ownership. Specifically, we propose that patients with schizophrenia have weaker stored body representations, and rely to a greater extent on external stimuli, such as visual information, due to imprecise or highly variable internal predictions. Moreover, the reduced sense of agency in schizophrenia may additionally contribute to the disturbed sense of body ownership, as evidence from healthy participants suggests that agency and body ownership are interrelated. Vice versa, a reduced sense of body ownership may also contribute to a reduced sense of agency. Future studies should explicitly target the precise relationship between the two in schizophrenia.
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Affiliation(s)
- Maayke Klaver
- Department of Experimental Psychology, Helmholtz Institute, Utrecht University CS Utrecht, Netherlands
| | - H Chris Dijkerman
- Department of Experimental Psychology, Helmholtz Institute, Utrecht University CS Utrecht, Netherlands
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47
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Lee KW, Chan KW, Chang WC, Lee EHM, Hui CLM, Chen EYH. A systematic review on definitions and assessments of psychotic-like experiences. Early Interv Psychiatry 2016; 10:3-16. [PMID: 25772746 DOI: 10.1111/eip.12228] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 12/19/2014] [Indexed: 01/26/2023]
Abstract
AIMS Psychotic-like experiences (PLEs) or subclinical psychotic experiences have received increased attention as some studies have suggested continuity between PLEs and psychotic disorders. However, epidemiological and correlational studies of PLEs showed mixed findings - it is observed that different studies use a wide variety of definitions of PLEs, as well as different assessment tools that are designed to capture such described experiences. The differences in definitions and assessment tools adopted could contribute to the discrepancy of findings. The current review aims to examine the definitions and assessment tools adopted in the studies of PLEs. METHODS Literature search was conducted between October 2013 and February 2014 using three search engines: Medline, Web of Science and PubMed. RESULTS A total of 76 papers met the selection criteria and were included in the current review. It is found that the majority of papers reviewed defined PLEs quantitatively using assessment tools and do not have a specific phenomenological definition, whereas assessment tools adopted have a wide variety. Furthermore, phenomenological studies of PLEs were rare. CONCLUSIONS The variations in definitions and assessment tools of PLEs might contribute to mixed findings in researches. Reaching to a consensus through the study of phenomenology of PLEs is essential to further advancement of the research in this area.
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Affiliation(s)
- Kit-Wai Lee
- Department of Psychiatry, The University of Hong Kong, Hong Kong
| | - Kit-Wa Chan
- Department of Psychiatry, The University of Hong Kong, Hong Kong
| | - Wing-Chung Chang
- Department of Psychiatry, The University of Hong Kong, Hong Kong
| | | | | | - Eric Yu-Hai Chen
- Department of Psychiatry, The University of Hong Kong, Hong Kong
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48
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Kállai J, Hegedüs G, Feldmann Á, Rózsa S, Darnai G, Herold R, Dorn K, Kincses P, Csathó Á, Szolcsányi T. Temperament and psychopathological syndromes specific susceptibility for rubber hand illusion. Psychiatry Res 2015; 229:410-9. [PMID: 26160198 DOI: 10.1016/j.psychres.2015.05.109] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 05/20/2015] [Accepted: 05/23/2015] [Indexed: 10/23/2022]
Abstract
The aim of this study is to explore individual capacity for self-integration, susceptibility to the Rubber Hand Illusion (RHI) and the role of temperament factors in the emergence of body schema and body image dissociation. The RHI factors, proprioceptive drift, body ownership and body disownership were assessed in 48 university students. Personality and psychiatric vulnerability were measured by the Temperament and Character Inventory (TCI-R) and the Symptom Checklist-90-R (SCL-90-R). Our study pointed to the fact that the extent of behaviourally defined proprioceptive drift was associated with temperament factors, especially with Novelty Seeking and Harm Avoidance. Further, the ownership was associated with Symptom Checklist factors, especially with elevated Interpersonal Sensitivity and vulnerability to Schizotypy and Paranoid Ideation and elevated disownership score was found in the case of elevated Schizotypy, including a depersonalisation feeling when the RHI was induced. The RHI may be considered as a conflicting situation, in which a way to cope with incongruent multimodal, visual, haptic and proprioceptive stimulation provides an opportunity to test body integration and embodiment processes in healthy participants and patients without disadvantageous outcomes. The results support and replenish the two opposite processing models of the RHI with a third, temperament-based procedural mechanism.
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Affiliation(s)
- János Kállai
- Institute of Behavioral Sciences, Medical Faculty University of Pécs, 7624-H Hungray.
| | - Gábor Hegedüs
- Institute of Behavioral Sciences, Medical Faculty University of Pécs, 7624-H Hungray.
| | - Ádám Feldmann
- Institute of Behavioral Sciences, Medical Faculty University of Pécs, 7624-H Hungray.
| | - Sándor Rózsa
- Department of Neurology, Medical Faculty, University of Pécs, 7624-H Hungray.
| | - Gergely Darnai
- Institute of Psychology, Eötvös Loránd University, Budapest, 1064-H Hungray.
| | - Róbert Herold
- Department of Psychiatry and Psychotherapy, Medical Faculty, University of Pécs, 7624-H Hungray.
| | - Krisztina Dorn
- Pediatric Clinic, Clinical Center, University of Pécs, 7623-H Hungray.
| | - Péter Kincses
- Institute of Behavioral Sciences, Medical Faculty University of Pécs, 7624-H Hungray.
| | - Árpád Csathó
- Institute of Behavioral Sciences, Medical Faculty University of Pécs, 7624-H Hungray
| | - Tibor Szolcsányi
- Institute of Behavioral Sciences, Medical Faculty University of Pécs, 7624-H Hungray.
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Yin H, Tully LM, Lincoln SH, Hooker CI. Adults with high social anhedonia have altered neural connectivity with ventral lateral prefrontal cortex when processing positive social signals. Front Hum Neurosci 2015; 9:469. [PMID: 26379532 PMCID: PMC4549656 DOI: 10.3389/fnhum.2015.00469] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 08/11/2015] [Indexed: 11/17/2022] Open
Abstract
Social anhedonia (SA) is a debilitating characteristic of schizophrenia, a common feature in individuals at psychosis-risk, and a vulnerability for developing schizophrenia-spectrum disorders. Prior work (Hooker et al., 2014) revealed neural deficits in the ventral lateral prefrontal cortex (VLPFC) when processing positive social cues in a community sample of people with high SA. Lower VLPFC neural activity was related to more severe self-reported schizophrenia-spectrum symptoms as well as the exacerbation of symptoms after social stress. In the current study, psycho-physiological interaction (PPI) analysis was applied to further investigate the neural mechanisms mediated by the VLPFC during emotion processing. PPI analysis revealed that, compared to low SA controls, participants with high SA exhibited reduced connectivity between the VLPFC and the motor cortex, the inferior parietal and the posterior temporal regions when viewing socially positive (relative to neutral) emotions. Across all participants, VLPFC connectivity correlated with behavioral and self-reported measures of attentional control, emotion management, and reward processing. Our results suggest that impairments to the VLPFC mediated neural circuitry underlie the cognitive and emotional deficits associated with social anhedonia, and may serve as neural targets for prevention and treatment of schizophrenia-spectrum disorders.
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Affiliation(s)
- Hong Yin
- Department of Psychology, Harvard University Cambridge, MA, USA
| | - Laura M Tully
- Psychiatry and Behavioral Sciences, University of California at Davis Sacramento, CA, USA ; Imaging Research Center, University of California at Davis Sacramento, CA, USA
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Louzolo A, Kalckert A, Petrovic P. When Passive Feels Active--Delusion-Proneness Alters Self-Recognition in the Moving Rubber Hand Illusion. PLoS One 2015; 10:e0128549. [PMID: 26090797 PMCID: PMC4474665 DOI: 10.1371/journal.pone.0128549] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 04/28/2015] [Indexed: 11/19/2022] Open
Abstract
Psychotic patients have problems with bodily self-recognition such as the experience of self-produced actions (sense of agency) and the perception of the body as their own (sense of ownership). While it has been shown that such impairments in psychotic patients can be explained by hypersalient processing of external sensory input it has also been suggested that they lack normal efference copy in voluntary action. However, it is not known how problems with motor predictions like efference copy contribute to impaired sense of agency and ownership in psychosis or psychosis-related states. We used a rubber hand illusion based on finger movements and measured sense of agency and ownership to compute a bodily self-recognition score in delusion-proneness (indexed by Peters' Delusion Inventory - PDI). A group of healthy subjects (n=71) experienced active movements (involving motor predictions) or passive movements (lacking motor predictions). We observed a highly significant correlation between delusion-proneness and self-recognition in the passive conditions, while no such effect was observed in the active conditions. This was seen for both ownership and agency scores. The result suggests that delusion-proneness is associated with hypersalient external input in passive conditions, resulting in an abnormal experience of the illusion. We hypothesize that this effect is not present in the active condition because deficient motor predictions counteract hypersalience in psychosis proneness.
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Affiliation(s)
- Anaïs Louzolo
- Department of clinical neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Andreas Kalckert
- Department of neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Predrag Petrovic
- Department of clinical neuroscience, Karolinska Institutet, Stockholm, Sweden
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