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Michael GA, Guyot D, Tarroux E, Comte M, Salgues S. Feeling Oneself Requires Embodiment: Insights From the Relationship Between Own-Body Transformations, Schizotypal Personality Traits, and Spontaneous Bodily Sensations. Front Psychol 2021; 11:578237. [PMID: 33424690 PMCID: PMC7786119 DOI: 10.3389/fpsyg.2020.578237] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 12/07/2020] [Indexed: 12/25/2022] Open
Abstract
Subtle bodily sensations such as itching or fluttering that occur in the absence of any external trigger (i.e., spontaneous sensations, or SPS) may serve to locate the spatial boundaries of the body. They may constitute the normal counterpart of extreme conditions in which body-related hallucinations and perceptual aberrations are experienced. Previous investigations have suggested that situations in which the body is spontaneously experienced as being deformed are related to the ability to perform own-body transformations, i.e., mental rotations of the body requiring disembodiment. We therefore decided to consider whether the perception of SPS might relate to embodiment as assessed through (i) the ability to perform own-body transformations (OBT task) and (ii) schizotypal traits (Schizotypal Personality Questionnaire, or SPQ), since high degrees of schizotypy in the general population have been associated with more vivid perceptions and aberrant perceptual experiences. Then participants completed a standard SPS task. Our analysis revealed that the slower the response time in the OBT task, the more frequent the perception of SPS. This suggests that difficulties in disembodying and mentally transforming one's own body facilitate feeling oneself. Furthermore, a greater number of correct responses in the OBT task was associated with less frequent perception of SPS. This suggests that finding it easier to disembody and perform mental own-body transformations interferes with the ability to sense oneself. The results also show that higher schizotypal traits, as assessed through the SPQ, are associated with more frequent perception of SPS. Taken together, these results provide a coherent picture and suggest that embodiment is required in order to correctly feel oneself, as expressed through the perception of SPS. The ability to easily experience disembodiment reduces the sense of feeling oneself, and proneness to schizotypal traits produces body misperceptions that enhance and amplify this feeling. The results are discussed in the light of current knowledge and theories about body representations, taking into account attention and interoception as factors that influence body awareness. We offer explanations for perceptual aberrations, body-related delusions, and hallucinations based on misperceived or misinterpreted SPS, and we discuss possible mechanisms that may contribute to feeling and misperceiving oneself.
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Affiliation(s)
- George A Michael
- University of Lyon, Lyon, France.,University Lyon 2, Laboratoire EMC (Cognitive Mechanisms Research Laboratory) (EA 3082), Lyon, France.,University Lyon 2, Institute of Psychology, Lyon, France
| | - Deborah Guyot
- University of Lyon, Lyon, France.,University Lyon 2, Laboratoire EMC (Cognitive Mechanisms Research Laboratory) (EA 3082), Lyon, France.,University Lyon 2, Institute of Psychology, Lyon, France
| | - Emilie Tarroux
- University of Lyon, Lyon, France.,University Lyon 2, Laboratoire EMC (Cognitive Mechanisms Research Laboratory) (EA 3082), Lyon, France.,University Lyon 2, Institute of Psychology, Lyon, France
| | - Mylène Comte
- University of Lyon, Lyon, France.,University Lyon 2, Laboratoire EMC (Cognitive Mechanisms Research Laboratory) (EA 3082), Lyon, France.,University Lyon 2, Institute of Psychology, Lyon, France
| | - Sara Salgues
- University of Lyon, Lyon, France.,University Lyon 2, Laboratoire EMC (Cognitive Mechanisms Research Laboratory) (EA 3082), Lyon, France.,University Lyon 2, Institute of Psychology, Lyon, France
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To the self and beyond: Arousal and functional connectivity of the temporo-parietal junction contributes to spontaneous sensations perception. Behav Brain Res 2020; 396:112880. [PMID: 32910970 DOI: 10.1016/j.bbr.2020.112880] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 07/27/2020] [Accepted: 08/19/2020] [Indexed: 01/29/2023]
Abstract
The temporoparietal junction (TPJ), along with the anterior insula (AI) and the extrastriate body area (EBA), play a major part in embodiment and self-awareness. However, these connections also appear to be frequently engaged in arousal and attentional processing of external events. Considering that these networks may focus attention both toward and away from the self, we set to investigate how they contribute to the perception of spontaneous sensations (SPS), a common phenomenon related to self-awareness and mediated by both interoceptive and attentional processes. In Experiment 1, resting-state EEG was recorded, as well as arousal reported via a questionnaire, followed by a SPS task. Functional TPJ-AI and TPJ-EBA connectivity were computed using eLORETA. Spatial correlational analyses showed that less frequent SPS coincided with greater TPJ-AI and TPJ-EBA functional connectivity, especially in the theta and alpha frequency bands. High self-reported arousal predicted low intensity and low confidence in the location of SPS. Resting-state skin conductance level (SCL) was recorded in Experiment 2, followed by the SPS task. Less frequent SPS coincided with greater SCL. Findings are interpreted in terms of attention and self-related processes, and a discussion of the TPJ participation in self-awareness through SPS is presented.
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Dafni‐Merom A, Peters‐Founshtein G, Kahana‐Merhavi S, Arzy S. A unified brain system of orientation and its disruption in Alzheimer's disease. Ann Clin Transl Neurol 2019; 6:2468-2478. [PMID: 31738022 PMCID: PMC6917329 DOI: 10.1002/acn3.50940] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 10/17/2019] [Indexed: 01/01/2023] Open
Abstract
OBJECTIVE To investigate whether a unified brain system manages one's orientation to different places, events and people in one's environment, and test the hypothesis that failure of this system (disorientation) is an early sign of Alzheimer's disease (AD). METHODS A total of 46 participants (patients along the AD continuum and cognitively normal control subjects) were tested in a personalized, ecologically valid task of orientation relating to the participant's own world in space, time and person under high-density electroencephalography. As a first step, we used evoked potential mapping to search for brain topography correlated with participants' performance in orientating themselves to different places (space), events (time) and people (person) (Experiment 1). We then compared behavioral and electrophysiological changes in patients along the AD continuum (Experiment 2). RESULTS We identified a specific brain topography ("orientation map") that was active for orientation in space, time and person in correlation to participants' performance. Both performance and the map's strength gradually decreased from health to mild cognitive impairment (MCI) and from MCI to AD. Another map, immediately preceding the orientation map, showed the longest activity in patients with MCI, significantly more than both patients with AD and cognitively normal controls. INTERPRETATION Our findings demonstrate that the same brain topography accounts for orientation in the different domains of space, time and person and provide a nexus between deterioration in patients' orientation with the aggravation of Alzheimer's disease.
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Affiliation(s)
- Amnon Dafni‐Merom
- Neuropsychiatry LaboratoryDepartment of Medical NeurobiologyFaculty of MedicineHebrew University of JerusalemJerusalemIsrael
- Department of NeurologyHadassah Hebrew University Medical CenterJerusalemIsrael
| | - Gregory Peters‐Founshtein
- Neuropsychiatry LaboratoryDepartment of Medical NeurobiologyFaculty of MedicineHebrew University of JerusalemJerusalemIsrael
- Department of NeurologyHadassah Hebrew University Medical CenterJerusalemIsrael
| | | | - Shahar Arzy
- Neuropsychiatry LaboratoryDepartment of Medical NeurobiologyFaculty of MedicineHebrew University of JerusalemJerusalemIsrael
- Department of NeurologyHadassah Hebrew University Medical CenterJerusalemIsrael
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Zouraraki C, Karamaouna P, Karagiannopoulou L, Giakoumaki SG. Schizotypy-Independent and Schizotypy-Modulated Cognitive Impairments in Unaffected First-Degree Relatives of Schizophrenia-spectrum Patients. Arch Clin Neuropsychol 2017; 32:1010-1025. [PMID: 28383650 DOI: 10.1093/arclin/acx029] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2016] [Accepted: 03/27/2017] [Indexed: 11/14/2022] Open
Abstract
Objective The aim of the study was to compare the neurocognitive profile of unaffected first-degree relatives of schizophrenia patients with control individuals, controlling for different schizotypal traits. Method One hundred and fifteen adult unaffected first-degree relatives of schizophrenia-spectrum patients and 122 controls were tested for schizotypy with the Schizotypal Personality Questionnaire. They also underwent a thorough neurocognitive assessment with a range of tasks covering several aspects of executive functioning. Between-group differences in cognition were examined first with multivariate analysis of variance and then with a series of multivariate analyses of covariance, including the schizotypal dimensions as covariates. Results The relatives had higher scores on all schizotypal dimensions compared with controls and poorer planning, problem solving, strategy formation and working memory, irrespective of schizotypal traits. They also scored lower in executive working memory and verbal fluency. The difference in executive working memory was sensitive to the effects of paranoid and negative schizotypy (both dimensions abolished the between-group difference) whereas the difference in verbal fluency was sensitive only to the effects of paranoid schizotypy. Neither cognitive-perceptual nor disorganized schizotypy accounted for any differences in neurocognition between relatives and the controls. Conclusions Impairments in planning, problem solving, strategy formation and working memory are "core" impairments in the schizophrenia-spectrum, possibly due to high heritability effects in these functions. Impairments in executive working memory and verbal fluency are associated with paranoid and negative schizotypy, possibly due to alterations in a common fronto-temporo-parietal neural network.
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Affiliation(s)
- Chrysoula Zouraraki
- Department of Psychology, Faculty of Social Sciences, University of Crete, Rethymno 74100, Crete, Greece
| | - Penny Karamaouna
- Department of Psychology, Faculty of Social Sciences, University of Crete, Rethymno 74100, Crete, Greece
| | - Leda Karagiannopoulou
- Department of Psychology, Faculty of Social Sciences, University of Crete, Rethymno 74100, Crete, Greece
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5
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Transcranial direct current stimulation of the right temporoparietal junction impairs third-person perspective taking. COGNITIVE AFFECTIVE & BEHAVIORAL NEUROSCIENCE 2017; 17:9-23. [PMID: 27649972 PMCID: PMC5272883 DOI: 10.3758/s13415-016-0462-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Given the current debates about the precise functional role of the right temporoparietal junction (rTPJ) in egocentric and exocentric perspective taking, in the present study we manipulated activity in the rTPJ to investigate the effects on a spatial perspective-taking task. Participants engaged in a mental body transformation task, requiring them to mentally rotate their own body to the position of an avatar, while undergoing anodal, cathodal, or sham transcranial direct current stimulation (tDCS) of the rTPJ. As a control task, participants judged the laterality of a stimulus feature with respect to a fixation cross on the screen. For the first half of the experiment (only during online tDCS), a task-selective effect of tDCS was observed, reflected in slower reaction times following anodal than following cathodal and sham tDCS for the mental body transformation task, but not for the control task. The effects of tDCS were most pronounced for stimuli implying a more difficult mental body transformation. No effects of tDCS were observed during the second half of the experiment. The effects of tDCS were most pronounced for participants scoring low on aberrant perceptual beliefs and spiritual transcendence, suggesting a relation between third-person perspective taking and bodily and perceptual experiences. The finding that anodal stimulation of the rTPJ impairs third-person perspective taking indicates a key role of this region in exocentric spatial processing.
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Katz J, Saadon-Grosman N, Arzy S. The life review experience: Qualitative and quantitative characteristics. Conscious Cogn 2017; 48:76-86. [DOI: 10.1016/j.concog.2016.10.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 10/04/2016] [Accepted: 10/21/2016] [Indexed: 01/07/2023]
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Brosey EA, Woodward ND. Neuroanatomical correlates of perceptual aberrations in psychosis. Schizophr Res 2017; 179:125-131. [PMID: 27729190 DOI: 10.1016/j.schres.2016.10.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 09/27/2016] [Accepted: 10/01/2016] [Indexed: 01/02/2023]
Abstract
BACKGROUND Aberrations in body perception are common in psychotic disorders. The insula and temporoparietal junction (TPJ) are involved in body ownership and spatial perception suggesting that abnormal structure of these regions might be related to the expression of perceptual aberrations in psychosis. METHODS 58 individuals with a primary psychotic disorder and 40 healthy subjects completed the Chapman Perceptual Aberration Scale (PAS) and underwent structural magnetic resonance imaging (MRI). Grey matter volume was extracted from a-priori defined TPJ, whole insula, and insula sub-division regions-of-interest (ROIs) and correlated with PAS scores. Additionally, a voxel-based morphometry (VBM) analysis examining the correlation between voxel-wise grey matter volume and PAS scores was conducted. RESULTS PAS scores in psychosis patients correlated with bilateral whole insula (right: r=-0.30, p=0.026; left: r=-0.35, p=0.011) and right TPJ (r=-0.27, p=0.024) volumes. The correlation between grey matter volume and PAS was strongest for the posterior sub-division of the insula (right: r=-0.32, p=0.017; left: r=-0.37, p=0.006). VBM analyses confirmed the ROI results: negative correlations with PAS were identified in clusters within the posterior and dorsal anterior insula, and the right TPJ. An exploratory, whole-brain analysis also revealed two additional regions located in the left middle orbitofrontal gyrus and left inferior temporal gyrus that inversely correlated with PAS scores. CONCLUSIONS Perceptual aberrations in individuals with psychosis are related to lower grey matter volume in the insula and TPJ. This relationship was strongest in the posterior region of the insula and right TPJ; brain areas that have been implicated in interoception and somesthesis.
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Affiliation(s)
- Erin A Brosey
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University School of Medicine, Nashville, TN 37212, USA
| | - Neil D Woodward
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University School of Medicine, Nashville, TN 37212, USA.
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Eddy CM. The junction between self and other? Temporo-parietal dysfunction in neuropsychiatry. Neuropsychologia 2016; 89:465-477. [PMID: 27457686 DOI: 10.1016/j.neuropsychologia.2016.07.030] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 05/13/2016] [Accepted: 07/22/2016] [Indexed: 11/18/2022]
Affiliation(s)
- Clare M Eddy
- Department of Neuropsychiatry, BSMHFT The Barberry, National Centre for Mental Health, Birmingham, UK; School of Clinical and Experimental Medicine, College of Medical and Dental Sciences, University of Birmingham, Birmingham, UK.
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9
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What Happens in Your Brain During Mental Dissociation? A Quest Towards Neural Markers of a Unified Sense of Self. Curr Behav Neurosci Rep 2016. [DOI: 10.1007/s40473-016-0063-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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10
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Borda JP, Sass LA. Phenomenology and neurobiology of self disorder in schizophrenia: Primary factors. Schizophr Res 2015; 169:464-473. [PMID: 26516103 DOI: 10.1016/j.schres.2015.09.024] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 09/16/2015] [Accepted: 09/18/2015] [Indexed: 12/13/2022]
Abstract
Schizophrenia is a heterogeneous syndrome, varying between persons and over course of illness. In this and a companion article, we argue that comprehension of this condition or set of conditions may require combining a phenomenological perspective emphasizing disorders of basic-self experience ("ipseity disturbance") with a multidimensional appreciation of possible neurobiological correlates--both primary and secondary. Previous attempts to link phenomenology and neurobiology generally focus on a single neurocognitive factor. We consider diverse aspects of schizophrenia in light of a diverse, albeit interacting, set of neurocognitive abnormalities, examining both synchronic (structural) interdependence and diachronic (temporal) succession. In this article we focus on the primary or foundational role of early perceptual and motoric disturbances that affect perceptual organization and especially intermodal or multisensory perceptual integration (“perceptual dys-integration”). These disturbances are discussed in terms of their implications for three interconnected aspects of selfhood in schizophrenia, primary forms of: disrupted "hold" or "grip" on the world, hyperreflexivity, diminished self-presence (self-affection). Disturbances of organization or integration imply forms of perceptual incoherence or diminished cognitive coordination. The effect is to disrupt one's ability to apprehend the world in holistic, vital, or contextually grounded fashion, or to fully identify with or experience the unity of one's own body or thinking--thereby generating an early and profound (albeit often subtle) disruption or diminishment of basic or core self and of the sense of existing in a coherent world. We discuss interrelationships or possible complementarities between these three aspects, and consider their relevance for a neurodevelopmental account of schizophrenia.
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Affiliation(s)
- Juan P Borda
- Dept of Mental Health, Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Louis A Sass
- Rutgers University, Piscataway, N.J. 08854, U.S.A.
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11
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Cohen AS, Mohr C, Ettinger U, Chan RCK, Park S. Schizotypy as an organizing framework for social and affective sciences. Schizophr Bull 2015; 41 Suppl 2:S427-35. [PMID: 25810057 PMCID: PMC4373637 DOI: 10.1093/schbul/sbu195] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Schizotypy, defined in terms of commonly occurring personality traits related to the schizophrenia spectrum, has been an important construct for understanding the neurodevelopment and stress-diathesis of schizophrenia. However, as schizotypy nears its sixth decade of application, it is important to acknowledge its impressively rich literature accumulating outside of schizophrenia research. In this article, we make the case that schizotypy has considerable potential as a conceptual framework for understanding individual differences in affective and social functions beyond those directly involved in schizophrenia spectrum pathology. This case is predicated on (a) a burgeoning literature noting anomalies in a wide range of social functioning, affiliative, positive and negative emotional, expressive, and social cognitive systems, (b) practical and methodological features associated with schizotypy research that help facilitate empirical investigation, and (c) close ties to theoretical constructs of central importance to affective and social science (eg, stress diathesis, neural compensation). We highlight recent schizotypy research, ie providing insight into the nature of affective and social systems more generally. This includes current efforts to clarify the neurodevelopmental, neurobiological, and psychological underpinnings of affiliative drives, hedonic capacity, social cognition, and stress responsivity systems. Additionally, we discuss neural compensatory and resilience factors that may mitigate the expression of stress-diathesis and functional outcome, and highlight schizotypy's potential role for understanding cultural determinants of social and affective functions.
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Affiliation(s)
- Alex S. Cohen
- Department of Psychology, Louisiana State University, Baton Rouge, LA;,*To whom correspondence should be addressed; Department of Psychology, Louisiana State University, 236 Audubon Hall, Baton Rouge, LA 70808, US; tel: 225-578-7017, fax: 225-578-4125, e-mail:
| | - Christine Mohr
- Institute of Psychology, University of Lausanne, Switzerland
| | | | - Raymond C. K. Chan
- Neuropsychology and Applied Cognitive Neuroscience Laboratory, Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
| | - Sohee Park
- Department of Psychology, Vanderbilt University, Nashville, TN
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12
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A novel manipulation method of human body ownership using an fMRI-compatible master–slave system. J Neurosci Methods 2014; 235:25-34. [DOI: 10.1016/j.jneumeth.2014.05.038] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 05/18/2014] [Accepted: 05/24/2014] [Indexed: 11/19/2022]
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13
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Embodied and disembodied allocentric simulation in high schizotypal subjects. Exp Brain Res 2014; 232:3023-33. [DOI: 10.1007/s00221-014-3991-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2013] [Accepted: 05/10/2014] [Indexed: 10/25/2022]
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Smith AM, Messier C. Voluntary Out-of-Body Experience: An fMRI Study. Front Hum Neurosci 2014; 8:70. [PMID: 24575000 PMCID: PMC3918960 DOI: 10.3389/fnhum.2014.00070] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 01/28/2014] [Indexed: 11/29/2022] Open
Abstract
The present single-case study examined functional brain imaging patterns in a participant that reported being able, at will, to produce somatosensory sensations that are experienced as her body moving outside the boundaries of her physical body all the while remaining aware of her unmoving physical body. We found that the brain functional changes associated with the reported extra-corporeal experience (ECE) were different than those observed in motor imagery. Activations were mainly left-sided and involved the left supplementary motor area and supramarginal and posterior superior temporal gyri, the last two overlapping with the temporal parietal junction that has been associated with out-of-body experiences. The cerebellum also showed activation that is consistent with the participant’s report of the impression of movement during the ECE. There was also left middle and superior orbital frontal gyri activity, regions often associated with action monitoring. The results suggest that the ECE reported here represents an unusual type of kinesthetic imagery.
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Affiliation(s)
- Andra M Smith
- School of Psychology, University of Ottawa , Ottawa, ON , Canada
| | - Claude Messier
- School of Psychology, University of Ottawa , Ottawa, ON , Canada
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Ettinger U, Meyhöfer I, Steffens M, Wagner M, Koutsouleris N. Genetics, cognition, and neurobiology of schizotypal personality: a review of the overlap with schizophrenia. Front Psychiatry 2014; 5:18. [PMID: 24600411 PMCID: PMC3931123 DOI: 10.3389/fpsyt.2014.00018] [Citation(s) in RCA: 185] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 02/06/2014] [Indexed: 01/22/2023] Open
Abstract
Schizotypy refers to a set of temporally stable traits that are observed in the general population and that resemble the signs and symptoms of schizophrenia. Here, we review evidence from studies on genetics, cognition, perception, motor and oculomotor control, brain structure, brain function, and psychopharmacology in schizotypy. We specifically focused on identifying areas of overlap between schizotypy and schizophrenia. Evidence was corroborated that significant overlap exists between the two, covering the behavioral brain structural and functional as well molecular levels. In particular, several studies showed that individuals with high levels of schizotypal traits exhibit alterations in neurocognitive task performance and underlying brain function similar to the deficits seen in patients with schizophrenia. Studies of brain structure have shown both volume reductions and increase in schizotypy, pointing to schizophrenia-like deficits as well as possible protective or compensatory mechanisms. Experimental pharmacological studies have shown that high levels of schizotypy are associated with (i) enhanced dopaminergic response in striatum following administration of amphetamine and (ii) improvement of cognitive performance following administration of antipsychotic compounds. Together, this body of work suggests that schizotypy shows overlap with schizophrenia across multiple behavioral and neurobiological domains, suggesting that the study of schizotypal traits may be useful in improving our understanding of the etiology of schizophrenia.
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Affiliation(s)
- Ulrich Ettinger
- Department of Psychology, University of Bonn , Bonn , Germany
| | - Inga Meyhöfer
- Department of Psychology, University of Bonn , Bonn , Germany
| | - Maria Steffens
- Department of Psychology, University of Bonn , Bonn , Germany
| | - Michael Wagner
- Department of Psychiatry and Psychotherapy, University of Bonn , Bonn , Germany
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Self-face recognition in schizophrenia is related to insight. Eur Arch Psychiatry Clin Neurosci 2013; 263:655-62. [PMID: 23494332 DOI: 10.1007/s00406-013-0400-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2011] [Accepted: 03/01/2013] [Indexed: 12/19/2022]
Abstract
A core feature of schizophrenia is the breakdown of the sense of self. A widespread clinical consequence of impaired self-awareness is a lack of insight. Self-face recognition is regarded as one aspect of self-awareness; how this relates to other self-referential processes such as insight into the disorder is as yet unknown. Nineteen patients with schizophrenia performed a facial recognition task using video morphings during which an average face gradually transformed into one's own, a famous or an unfamiliar face (and vice versa). Reaction times to detect faces during the transitions were compared between patients and a matched control group. In the patient group, we also examined correlations between face recognition and insight, psychopathology, and self-evaluation. Both patients with schizophrenia and controls recognised their own faces faster than unfamiliar faces. Whereas healthy subjects recognised a famous face at an intermediate speed that did not differ significantly from the recognition of one's own and unfamiliar faces, schizophrenia patients recognised the famous face, similar to their own face, significantly faster than an unfamiliar face. Moreover, in the patient group, higher insight correlated with faster reaction times in distinguishing one's own from famous faces. Patients with schizophrenia seem to distinguish less than controls between their own and a famous face relative to an unfamiliar face. Patients with good insight into the disorder, however, were better able to differentiate between their own and a famous face. This study supports the view that self-face recognition is an indicator for higher-order self-awareness.
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Conson M, Trojano L, Vitale C, Mazzarella E, Allocca R, Barone P, Grossi D, Santangelo G. The role of embodied simulation in mental transformation of whole-body images: evidence from Parkinson's disease. Hum Mov Sci 2013; 33:343-53. [PMID: 24290611 DOI: 10.1016/j.humov.2013.10.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Revised: 10/23/2013] [Accepted: 10/24/2013] [Indexed: 12/13/2022]
Abstract
It has been repeatedly demonstrated that mentally performing an action and mentally transforming body-parts entail simulation of one's own body movements, consistent with predictions of embodied cognition theories. However, the involvement of embodied simulation in mental transformation of whole-body images is still disputed. Here, we assessed own body transformation in Parkinson's disease (PD) patients with symptoms most affecting the left or the right body side. PD patients were required to perform left-right judgments on front-facing or back-facing human figures, and a letter rotation task. Results demonstrated that PD patients were selectively impaired in judging the side of back-facing human figures corresponding to their own most affected side, but performed as well as healthy subjects on mental transformation of front-facing bodies and on letter rotation. These findings demonstrate a parallel impairment between motor and mental simulation mechanisms in PD patients, thus highlighting the specific contribution of embodied cognition to mental transformation of whole-body images.
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Affiliation(s)
- Massimiliano Conson
- Neuropsychology Laboratory, Department of Psychology, Second University of Naples, Viale Ellittico 31, 81100 Caserta, Italy.
| | - Luigi Trojano
- Neuropsychology Laboratory, Department of Psychology, Second University of Naples, Viale Ellittico 31, 81100 Caserta, Italy; Salvatore Maugeri Foundation, IRCCS Institute of Telese Terme (BN), Italy
| | - Carmine Vitale
- IDC "Hermitage-Capodimonte", Naples, Italy; University of Naples Parthenope, Naples, Italy
| | - Elisabetta Mazzarella
- Department of Neuromotor Physiology, Scientific Institute Foundation Santa Lucia, Via Ardeatina 306, 00179 Rome, Italy
| | - Roberto Allocca
- Department of Neurological Sciences, University Federico II, Naples, Italy
| | - Paolo Barone
- IDC "Hermitage-Capodimonte", Naples, Italy; Neurodegenerative Diseases Center, University of Salerno, Salerno, Italy
| | - Dario Grossi
- Neuropsychology Laboratory, Department of Psychology, Second University of Naples, Viale Ellittico 31, 81100 Caserta, Italy
| | - Gabriella Santangelo
- Neuropsychology Laboratory, Department of Psychology, Second University of Naples, Viale Ellittico 31, 81100 Caserta, Italy; IDC "Hermitage-Capodimonte", Naples, Italy.
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A Tutorial on Data-Driven Methods for Statistically Assessing ERP Topographies. Brain Topogr 2013; 27:72-83. [DOI: 10.1007/s10548-013-0310-1] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Accepted: 08/14/2013] [Indexed: 10/26/2022]
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Rektor I, Schachter SC, Arzy S, Baloyannis SJ, Bazil C, Brázdil M, Engel J, Helmstaedter G, Hesdorffer DC, Jones-Gotman M, Kesner L, Komárek V, Krämer G, Leppik IE, Mann MW, Mula M, Risse GL, Stoker GW, Kasteleijn-Nolst Trenité DGA, Trimble M, Tyrliková I, Korczyn AD. Epilepsy, behavior, and art (Epilepsy, Brain, and Mind, part 1). Epilepsy Behav 2013; 28:261-82. [PMID: 23764495 DOI: 10.1016/j.yebeh.2013.03.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/28/2013] [Indexed: 01/22/2023]
Abstract
Epilepsy is both a disease of the brain and the mind. Brain diseases, structural and/or functional, underlie the appearance of epilepsy, but the notion of epilepsy is larger and cannot be reduced exclusively to the brain. We can therefore look at epilepsy from two angles. The first perspective is intrinsic: the etiology and pathophysiology, problems of therapy, impact on the brain networks, and the "mind" aspects of brain functions - cognitive, emotional, and affective. The second perspective is extrinsic: the social interactions of the person with epilepsy, the influence of the surrounding environment, and the influences of epilepsy on society. All these aspects reaching far beyond the pure biological nature of epilepsy have been the topics of two International Congresses of Epilepsy, Brain, and Mind that were held in Prague, Czech Republic, in 2010 and 2012 (the third Congress will be held in Brno, Czech Republic on April 3-5, 2014; www.epilepsy-brain-mind2014.eu). Here, we present the first of two papers with extended summaries of selected presentations of the 2012 Congress that focused on epilepsy, behavior, and art.
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Affiliation(s)
- Ivan Rektor
- Masaryk University, Brno Epilepsy Center, St. Anne's Hospital and School of Medicine, and Central European Institute of Technology (CEITEC), Brno, Czech Republic
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Mohr C, Rowe AC, Kurokawa I, Dendy L, Theodoridou A. Bodily perspective taking goes social: the role of personal, interpersonal, and intercultural factors. JOURNAL OF APPLIED SOCIAL PSYCHOLOGY 2013. [DOI: 10.1111/jasp.12093] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Hippocampal physiology, structure and function and the neuroscience of schizophrenia: a unified account of declarative memory deficits, working memory deficits and schizophrenic symptoms. Behav Sci (Basel) 2013; 3:298-315. [PMID: 25379240 PMCID: PMC4217628 DOI: 10.3390/bs3020298] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 05/30/2013] [Accepted: 06/08/2013] [Indexed: 01/06/2023] Open
Abstract
Memory impairment is a consistent feature of the schizophrenic syndrome. Hippocampal dysfunction has also been consistently demonstrated. This review will discuss neurophysiological and neuroanatomical aspects of memory formation and how they relate to memory impairment in schizophrenia. An understanding of the cellular physiology and connectivity of the hippocampus with other regions can also aid in understanding the relationship between schizophrenic declarative or relational memory deficits, working memory deficits and the clinical symptoms of the syndrome.
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Knyazev GG. EEG correlates of self-referential processing. Front Hum Neurosci 2013; 7:264. [PMID: 23761757 PMCID: PMC3674309 DOI: 10.3389/fnhum.2013.00264] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 05/24/2013] [Indexed: 11/13/2022] Open
Abstract
Self-referential processing has been principally investigated using functional magnetic resonance imaging (fMRI). However, understanding of the brain functioning is not possible without careful comparison of the evidence coming from different methodological domains. This paper aims to review electroencephalographic (EEG) studies of self-referential processing and to evaluate how they correspond, complement, or contradict the existing fMRI evidence. There are potentially two approaches to the study of EEG correlates of self-referential processing. Firstly, because simultaneous registration of EEG and fMRI has become possible, the degree of overlap between these two signals in brain regions related to self-referential processing could be determined. Second and more direct approach would be the study of EEG correlates of self-referential processing per se. In this review, I discuss studies, which employed both these approaches and show that in line with fMRI evidence, EEG correlates of self-referential processing are most frequently found in brain regions overlapping with the default network, particularly in the medial prefrontal cortex. In the time domain, the discrimination of self- and others-related information is mostly associated with the P300 ERP component, but sometimes is observed even earlier. In the frequency domain, different frequency oscillations have been shown to contribute to self-referential processing, with spontaneous self-referential mentation being mostly associated with the alpha frequency band.
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Affiliation(s)
- Gennady G Knyazev
- Institute of Physiology, Siberian Branch of Russian Academy of Medical Sciences , Novosibirsk , Russia
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23
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Theodoridou A, Rowe AC, Mohr C. Men perform comparably to women in a perspective taking task after administration of intranasal oxytocin but not after placebo. Front Hum Neurosci 2013; 7:197. [PMID: 23754995 PMCID: PMC3664327 DOI: 10.3389/fnhum.2013.00197] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 04/27/2013] [Indexed: 11/13/2022] Open
Abstract
Oxytocin (OT) is thought to play an important role in human interpersonal information processing and behavior. By inference, OT should facilitate empathic responding, i.e., the ability to feel for others and to take their perspective. In two independent double-blind, placebo-controlled between-subjects studies, we assessed the effect of intranasally administered OT on affective empathy and perspective taking, whilst also examining potential sex differences (e.g., women being more empathic than men). In study 1, we provided 96 participants (48 men) with an empathy scenario and recorded self-reports of empathic reactions to the scenario, while in study 2, a sample of 120 individuals (60 men) performed a computerized implicit perspective taking task. Whilst results from Study 1 showed no influence of OT on affective empathy, we found in Study 2 that OT exerted an effect on perspective taking ability in men. More specifically, men responded faster than women in the placebo group but they responded as slowly as women in the OT group. We conjecture that men in the OT group adopted a social perspective taking strategy, such as did women in both groups, but not men in the placebo group. On the basis of results across both studies, we suggest that self-report measures (such as used in Study 1) might be less sensitive to OT effects than more implicit measures of empathy such as that used in Study 2. If these assumptions are confirmed, one could infer that OT effects on empathic responses are more pronounced in men than women, and that any such effect is best studied using more implicit measures of empathy rather than explicit self-report measures.
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Affiliation(s)
| | - Angela C. Rowe
- School of Experimental Psychology, University of BristolBristol, UK
| | - Christine Mohr
- Institute of Psychology, University of LausanneLausanne, Switzerland
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Molnar-Szakacs I, Arzy S. Searching for an integrated self-representation. Commun Integr Biol 2013; 2:365-7. [PMID: 19721893 DOI: 10.4161/cib.2.4.8290] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2009] [Accepted: 02/24/2009] [Indexed: 11/19/2022] Open
Abstract
Recent inquiries into the nature of self-representation have put forward a new and interesting conceptualization of the self, as a "center of gravity" of one's private and social behavior. We review recent neuroimaging work that has suggested interactions among brain regions comprising the default state network, including medial and temporo-parietal cortical regions and the mirror neuron system including lateral fronto-parietal regions as two interacting neural systems that work in concert to produce a cohesive self-representation through simulation. Simulation processes-broadly construed here as using existing representations as templates for understanding novel information-are instantiated by these brain systems across a wide range of domains including time, space, physical and social, giving rise to the multifaceted Self that we all are. Accumulating evidence also suggests, that these simulation processes are used in a multitude of cognitions that constitute the self, including autobiographical memory and prospection, perspective taking, understanding other's actions and mental states and embodied self-representation.
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Affiliation(s)
- Istvan Molnar-Szakacs
- Tennenbaum Center for the Biology of Creativity; Semel Institute for Neuroscience and Human Behavior; Department of Psychiatry and Biobehavioral Sciences; David Geffen School of Medicine; University of California, Los Angeles, USA
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Kühn S, Schubert F, Gallinat J. Higher prefrontal cortical thickness in high schizotypal personality trait. J Psychiatr Res 2012; 46:960-5. [PMID: 22551659 DOI: 10.1016/j.jpsychires.2012.04.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Revised: 03/07/2012] [Accepted: 04/05/2012] [Indexed: 10/28/2022]
Abstract
A model of schizophrenia-spectrum disorders hypothesized that schizotypy shares biomarkers with schizophrenia but due to protective factors such as a greater prefrontal cortex those individuals have a reduced vulnerability to schizophrenia. In contrast to previous studies exploring volumetric brain correlates of schizotypy focussing on clinical samples or relying on between-group comparisons we measured cortical thickness and correlated it with the expression of schizotypal personality traits in a mentally healthy sample. We acquired high-resolution MRI scans from 34 subjects and used FreeSurfer to model the grey-white and pial surfaces for each individual cortex in order to compute the distance between these surfaces to obtain a measure of cortical thickness. Differences in cortical thickness were correlated with positive and negative factors of schizotypy as assessed by means of the schizotypal personality questionnaire. We found a significant positive correlation between right dorso-lateral prefrontal cortex (DLPFC) and right dorsal premotor cortex/frontal eye fields (dPMC/FEF) and the total schizotypy score, between right DLPFC and the positive factor, and between right temporo-parietal junction and the negative factor of schizotypy. The volume of thalamus was negatively correlated with schizotypy. A significant negative correlation between thalamus volume and dPMC/FEF cortical thickness was observed. One may speculate that this finding is in line with the hypothesis of a compensatory role of greater prefrontal cortex in schizotypy in healthy populations.
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Affiliation(s)
- Simone Kühn
- Charité University Medicine, St. Hedwig Krankenhaus, Clinic for Psychiatry and Psychotherapy, Große Hamburger Straße 5-11, 10115 Berlin, Germany.
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Cognitive and prepulse inhibition deficits in psychometrically high schizotypal subjects in the general population: relevance to schizophrenia research. J Int Neuropsychol Soc 2012; 18:643-56. [PMID: 22613272 DOI: 10.1017/s135561771200029x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Schizophrenia and schizotypal personality disorder share common clinical profiles, neurobiological and genetic substrates along with Prepulse Inhibition and cognitive deficits; among those, executive, attention, and memory dysfunctions are more consistent. Schizotypy is considered to be a non-specific "psychosis-proneness," and understanding the relationship between schizotypal traits and cognitive function in the general population is a promising approach for endophenotypic research in schizophrenia spectrum disorders. In this review, findings for executive function, attention, memory, and Prepulse Inhibition impairments in psychometrically defined schizotypal subjects have been summarized and compared to schizophrenia patients and their unaffected first-degree relatives. Cognitive flexibility, sustained attention, working memory, and Prepulse Inhibition impairments were consistently reported in high schizotypal subjects in accordance to schizophrenia patients. Genetic studies assessing the effects of various candidate gene polymorphisms in schizotypal traits and cognitive function are promising, further supporting a polygenic mode of inheritance. The implications of the findings, methodological issues, and suggestions for future research are discussed.
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Gardner MR, Sorhus I, Edmonds CJ, Potts R. Sex differences in components of imagined perspective transformation. Acta Psychol (Amst) 2012; 140:1-6. [PMID: 22426425 DOI: 10.1016/j.actpsy.2012.02.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2011] [Revised: 02/02/2012] [Accepted: 02/06/2012] [Indexed: 01/19/2023] Open
Abstract
Little research to date has examined whether sex differences in spatial ability extend to the mental self rotation involved in taking on a third party perspective. This question was addressed in the present study by assessing components of imagined perspective transformations in twenty men and twenty women. Participants made speeded left-right judgements about the hand in which an object was held by front- and back- facing schematic human figures in an "own body transformation task." Response times were longer when the figure did not share the same spatial orientation as the participant, and were substantially longer than those made for a control task requiring left-right judgements about the same stimuli from the participant's own point of view. A sex difference in imagined perspective transformation favouring males was found to be restricted to the speed of imagined self rotation, and was not observed for components indexing readiness to take a third party point of view, nor in left-right confusion. These findings indicate that the range of spatial abilities for which a sex difference has been established should be extended to include imagined perspective transformations. They also suggest that imagined perspective transformations may not draw upon those empathic social-emotional perspective taking processes for which females show an advantage.
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Affiliation(s)
- Mark R Gardner
- Department of Psychology, University of Westminster, 309 Regent Street, London, W1B 2UW, United Kingdom.
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28
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Venneri A, Pentore R, Cobelli M, Nichelli P, Shanks MF. Translocation of the embodied self without visuospatial neglect. Neuropsychologia 2012; 50:973-8. [PMID: 22349442 DOI: 10.1016/j.neuropsychologia.2012.02.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Revised: 01/27/2012] [Accepted: 02/03/2012] [Indexed: 10/28/2022]
Abstract
This is the case report of RB, a 68-year-old retired woman who, following an extensive right sided ischaemic stroke, showed hemiplegia, anosognosia and allochiria, but no somato-sensory deficits and no visuospatial neglect. A high resolution 3D MRI structural scan of her brain was acquired to define the structural damage in detail. Morphometric analyses of grey and white matter data revealed a large lesion which involved most of her right parietal, temporal, and mesial frontal cortex, with partial sparing of the right dorsolateral prefrontal cortex and part of the posterior corpus callosum. Detailed examination showed that RB attributed sensory stimuli, both on the left and on the right, to the opposite side of her body. This mirror reversed representation of her body caused misattribution of items even in the absence of stimulation, as for instance when the patient spontaneously reported pain in her right knee while pointing to her left knee. RB's neuropsychological profile showed normal or borderline performance on most cognitive tasks. Language comprehension was intact and she could tell left from right without difficulty in all instances except for those referable to her soma. To our knowledge this is the first description of severe allochiria for body representation in the absence of neglect. The evidence from this case supports the developing concept that the body representation is not simply a systematic registration of proprioceptive inputs, but that the brain has a more sophisticated high level representation of one's body map which is updated on the basis of multimodal information.
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Affiliation(s)
- Annalena Venneri
- Department of Neuroscience, University of Sheffield and Sheffield Teaching Hospital NHS Foundation Trust, Sheffield, UK.
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29
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Thakkar KN, Nichols HS, McIntosh LG, Park S. Disturbances in body ownership in schizophrenia: evidence from the rubber hand illusion and case study of a spontaneous out-of-body experience. PLoS One 2011; 6:e27089. [PMID: 22073126 PMCID: PMC3205058 DOI: 10.1371/journal.pone.0027089] [Citation(s) in RCA: 160] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2011] [Accepted: 10/10/2011] [Indexed: 11/25/2022] Open
Abstract
Background A weakened sense of self may contribute to psychotic experiences. Body ownership, one component of self-awareness, can be studied with the rubber hand illusion (RHI). Watching a rubber hand being stroked while one's unseen hand is stroked synchronously can lead to a sense of ownership over the rubber hand, a shift in perceived position of the real hand, and a limb-specific drop in stimulated hand temperature. We aimed to assess the RHI in schizophrenia using quantifiable measures: proprioceptive drift and stimulation-dependent changes in hand temperature. Methods The RHI was elicited in 24 schizophrenia patients and 21 matched controls by placing their unseen hand adjacent to a visible rubber hand and brushing real and rubber hands synchronously or asynchronously. Perceived finger location was measured before and after stimulation. Hand temperature was taken before and during stimulation. Subjective strength of the illusion was assessed by a questionnaire. Results Across groups, the RHI was stronger during synchronous stimulation, indicated by self-report and proprioceptive drift. Patients reported a stronger RHI than controls. Self-reported strength of RHI was associated with schizotypy in controls Proprioceptive drift was larger in patients, but only following synchronous stimulation. Further, we observed stimulation-dependent changes in skin temperature. During right hand stimulation, temperature dropped in the stimulated hand and rose in the unstimulated hand. Interestingly, induction of RHI led to an out-of-body experience in one patient, linking body disownership and psychotic experiences. Conclusions The RHI is quantitatively and qualitatively stronger in schizophrenia. These findings suggest that patients have a more flexible body representation and weakened sense of self, and potentially indicate abnormalities in temporo-parietal networks implicated in body ownership. Further, results suggest that these body ownership disturbances might be at the heart of a subset of the pathognomonic delusions of passivity.
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Affiliation(s)
- Katharine N. Thakkar
- Department of Psychology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Heathman S. Nichols
- Department of Psychology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Lindsey G. McIntosh
- Department of Psychology, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Sohee Park
- Department of Psychology, Vanderbilt University, Nashville, Tennessee, United States of America
- Department of Psychiatry, Vanderbilt University Medical College, Nashville, Tennessee, United States of America
- * E-mail:
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Gardner MR, Potts R. Domain general mechanisms account for imagined transformations of whole body perspective. Acta Psychol (Amst) 2011; 137:371-81. [PMID: 21596360 DOI: 10.1016/j.actpsy.2011.04.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Revised: 04/01/2011] [Accepted: 04/19/2011] [Indexed: 11/27/2022] Open
Abstract
Three experiments investigated the contribution of domain general processes to imagined transformations of whole body perspective. In a task where participants make left-right judgements about a schematic human figure, reaction times made from the point of view of the figure are longer when the figure does not share the same spatial orientation as the participant and are substantially longer than those made from the participant's own point of view. These phenomena have been attributed to a specialised mechanism for imagined perspective transformations. In the present experiments, the effect of orientation on performance was influenced by factors that affect spatial stimulus-response (S-R) compatibility; it was attenuated with reduced dimensional overlap and reversed by crossed S-R mappings. Performance in a control experiment in which no figure was present suggests that processes moderating S-R mappings may account for the effect of adopting another's point of view. Our findings demonstrate a role for domain general processes in imagined transformations of whole body perspective, imply that egocentric codes for spatial relationships within visually presented bodies are automatically generated, and undermine evidence for a specialised mechanism for imagined perspective transformations.
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Urgesi C, Fornasari L, De Faccio S, Perini L, Mattiussi E, Ciano R, Balestrieri M, Fabbro F, Brambilla P. Body schema and self-representation in patients with bulimia nervosa. Int J Eat Disord 2011; 44:238-48. [PMID: 20186715 DOI: 10.1002/eat.20816] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Neuroimaging evidences in eating disorder (ED) patients document dysfunctional neural activity of the posterior parietal cortex, which is engaged in the representation of body schema. Yet a full neuropsychological investigation of body schema representation in ED patients is lacking. We examined mental imagery and body schema representation in patients with bulimia nervosa (BN) and binge eating disorder (BED). METHOD Consecutive samples of 15 BN patients and 15 BED patients were compared with two groups of 15 age-matched controls in tasks requiring body or object mental transformation. RESULTS BN, but not BED patients, were selectively impaired in the mental transformation of their own body, although this deficit was not correlated with measures of body dissatisfaction. In contrast, no patient group was impaired in the mental transformation of external objects. DISCUSSION Results showed altered self-body representation in BN, but not BED patients, as the neuropsychological consequences of posterior parietal cortex dysfunctions.
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Affiliation(s)
- Cosimo Urgesi
- Department of Philosophy, University of Udine, Udine, Italy.
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Asai T, Mao Z, Sugimori E, Tanno Y. Rubber hand illusion, empathy, and schizotypal experiences in terms of self-other representations. Conscious Cogn 2011; 20:1744-50. [PMID: 21371911 DOI: 10.1016/j.concog.2011.02.005] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2010] [Revised: 02/01/2011] [Accepted: 02/05/2011] [Indexed: 11/19/2022]
Abstract
When participants observed a rubber hand being touched, their sense of touch was activated (rubber hand illusion: RHI). While this illusion might be caused by multi-modal integration, it may also be related to empathic function, which enables us to simulate the observed information. We examined individual differences in the RHI, including empathic and schizotypal personality traits, as previous research had suggested that schizophrenic patients would be more subject to the RHI. The results indicated that people who experience a stronger RHI might have stronger empathic and schizotypal personalites simultaneously. We discussed these relationships in terms of self-other representations.
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Affiliation(s)
- Tomohisa Asai
- Department of Cognitive and Behavioral Science, Graduate School of Arts and Sciences, University of Tokyo, Japan.
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Arzy S, Mohr C, Molnar-Szakacs I, Blanke O. Schizotypal perceptual aberrations of time: correlation between score, behavior and brain activity. PLoS One 2011; 6:e16154. [PMID: 21267456 PMCID: PMC3022658 DOI: 10.1371/journal.pone.0016154] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2010] [Accepted: 12/14/2010] [Indexed: 11/22/2022] Open
Abstract
A fundamental trait of the human self is its continuum experience of space and time. Perceptual aberrations of this spatial and temporal continuity is a major characteristic of schizophrenia spectrum disturbances – including schizophrenia, schizotypal personality disorder and schizotypy. We have previously found the classical Perceptual Aberration Scale (PAS) scores, related to body and space, to be positively correlated with both behavior and temporo-parietal activation in healthy participants performing a task involving self-projection in space. However, not much is known about the relationship between temporal perceptual aberration, behavior and brain activity. To this aim, we composed a temporal Perceptual Aberration Scale (tPAS) similar to the traditional PAS. Testing on 170 participants suggested similar performance for PAS and tPAS. We then correlated tPAS and PAS scores to participants' performance and neural activity in a task of self-projection in time. tPAS scores correlated positively with reaction times across task conditions, as did PAS scores. Evoked potential mapping and electrical neuroimaging showed self-projection in time to recruit a network of brain regions at the left anterior temporal cortex, right temporo-parietal junction, and occipito-temporal cortex, and duration of activation in this network positively correlated with tPAS and PAS scores. These data demonstrate that schizotypal perceptual aberrations of both time and space, as reflected by tPAS and PAS scores, are positively correlated with performance and brain activation during self-projection in time in healthy individuals along the schizophrenia spectrum.
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Affiliation(s)
- Shahar Arzy
- Laboratory of Cognitive Neuroscience, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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34
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Gardner MR, Potts R. Hand dominance influences the processing of observed bodies. Brain Cogn 2010; 73:35-40. [DOI: 10.1016/j.bandc.2010.02.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Revised: 02/12/2010] [Accepted: 02/20/2010] [Indexed: 10/19/2022]
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Rapp AM, Mutschler DE, Wild B, Erb M, Lengsfeld I, Saur R, Grodd W. Neural correlates of irony comprehension: the role of schizotypal personality traits. BRAIN AND LANGUAGE 2010; 113:1-12. [PMID: 20071019 DOI: 10.1016/j.bandl.2009.11.007] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2009] [Revised: 10/06/2009] [Accepted: 11/21/2009] [Indexed: 05/28/2023]
Abstract
To detect that a conversational turn is intended to be ironic is a difficult challenge in everyday language comprehension. Most authors suggested a theory of mind deficit is crucial for irony comprehension deficits in psychiatric disorders like schizophrenia; however, the underlying pathophysiology and neurobiology are unknown and recent research highlights the possible role of language comprehension abnormalities. Fifteen female right-handed subjects completed personality testing as well as functional magnetic resonance imaging (fMRI) and neuropsychology. Subjects were recruited from the general population. No subject had a lifetime history of relevant psychiatric disorder; however, subjects differed in their score on the German version of the schizotypal personality questionnaire (SPQ). During fMRI scans, the subjects silently read 44 short text vignettes that ended in either an ironic or a literal statement. Imaging was performed using a 3 T Siemens scanner. The influence of schizotypy on brain activation was investigated by using an SPM5 regression analysis with the SPQ total score and the SPQ cognitive-perceptual score as regressors. Reading ironic in contrast to literal sentences activated a bilateral network including left medial prefrontal and left inferior parietal gyri. During reading of ironic sentences, brain activation in the middle temporal gyrus of both hemispheres showed a significant negative association with the SPQ total score and the SPQ cognitive-perceptual score. Significant positive correlation with the SPQ total score was present in the left inferior frontal gyrus. We conclude schizotypal personality traits are associated with a dysfunctional lateral temporal language rather than a theory of mind network.
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Affiliation(s)
- A M Rapp
- Department of Psychiatry, University of Tuebingen, Osianderstrasse 26, Tuebingen, Germany.
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36
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Mental Imagery for Full and Upper Human Bodies: Common Right Hemisphere Activations and Distinct Extrastriate Activations. Brain Topogr 2010; 23:321-32. [DOI: 10.1007/s10548-010-0138-x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Accepted: 02/12/2010] [Indexed: 11/25/2022]
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Britz J, Michel CM. Errors can be related to pre-stimulus differences in ERP topography and their concomitant sources. Neuroimage 2009; 49:2774-82. [PMID: 19850140 DOI: 10.1016/j.neuroimage.2009.10.033] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2009] [Revised: 10/09/2009] [Accepted: 10/12/2009] [Indexed: 10/20/2022] Open
Abstract
Much of the variation in both neuronal and behavioral responses to stimuli can be explained by pre-stimulus fluctuations in brain activity. We hypothesized that also errors are the result of stochastic fluctuations in pre-stimulus activity and investigated the temporal dynamics of the scalp topography and their concomitant intracranial generators of stimulus- and response-locked high-density event-related potentials (ERPs) to errors and correct trials in a Stroop task. We found significant differences in ERP map topography and intracranial sources before the onset of the stimulus and after the initiation of the response but not as a function of stimulus-induced conflict. Before the stimulus, topographic differences were accompanied by differential activity in lateral frontal, parietal and temporal areas known to be involved in voluntary reorientation of attention and cognitive control. Differential post-response activity propagated both medially and laterally on a rostral-caudal axis of a network typically involved in performance monitoring. Analysis of the statistical properties of error occurrences revealed their stochasticity.
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Affiliation(s)
- Juliane Britz
- Department of Fundamental Neuroscience, Centre Médical Universitaire, University of Geneva, 1 Rue Michel Servet, CH-1211 Geneva, Switzerland. juliane.britz@unige
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38
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Schwabe L, Lenggenhager B, Blanke O. The timing of temporoparietal and frontal activations during mental own body transformations from different visuospatial perspectives. Hum Brain Mapp 2009; 30:1801-12. [PMID: 19343800 DOI: 10.1002/hbm.20764] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The perspective from where the world is perceived is an important aspect of the bodily self and may break down in neurological conditions such as out-of-body experiences (OBEs). These striking disturbances are characterized by disembodiment, an external perspective and have been observed after temporoparietal damage. Using mental own body imagery, recent neuroimaging work has linked perspectival changes to the temporoparietal cortex. Because the disembodied perspective during OBEs is elevated in the majority of cases, we tested whether an elevated perspective will interfere with such temporoparietal mechanisms mental own body imagery. We designed stimuli of life-sized humans rotated around the vertical axis and rendered as if viewed from three different perspectives: elevated, lowered, and normal. Reaction times (RTs) in an own body transformation task, but not the control condition, were dependent on the rotation angle. Furthermore, RTs were shorter for the elevated as compared with the normal or lowered perspective. Using high-density EEG and evoked potential (EP) mapping, we found a bilateral temporoparietal and frontal activation at approximately 330-420 ms after stimulus onset that was dependent on the rotation angle, but not on the perspective. This activation was also found in response-locked EPs. In the time period approximately 210-330 ms we found a temporally distinct posterior temporal activation with its duration being dependent on the perspective, but not the rotation angle. Collectively, the present findings suggest that temporoparietal and frontal as well as posterior temporal activations and their timing are crucial neuronal correlates of the bodily self as studied by mental imagery.
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Affiliation(s)
- Lars Schwabe
- Department of Computer Science and Electrical Engineering, Laboratory of Adaptive and Regenerative Software Systems, Albert-Einstein-Strasse 21, Rostock, Germany.
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39
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Nahum L, Morand S, Barcellona-Lehmann S, Schnider A. Instinctive modulation of cognitive behavior: a human evoked potential study. Hum Brain Mapp 2009; 30:2120-31. [PMID: 18781593 DOI: 10.1002/hbm.20654] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Successful adaptive behavior requires fast information processing. Behavioral switches may be necessary in response to threatening stimuli or when anticipated outcomes fail to occur. In this study, we explored the cortical processing of these two components using high-resolution evoked potentials. Subjects made a reversal learning task where they had to predict which one of two faces had a target stimulus on the nose. We found early electrocortical differences at 100-200 ms depending on whether the target stimulus was a spider or a disk. Source estimation indicated that this distinction was mediated by an anterior medial temporal region including the amygdala and adjacent cortex. When a switch to the alternate face was required, there was a discrete early electrocortical correlate after 200 ms, mediated by ventromedial prefrontal areas. Continued validity of stimulus-target associations was signaled at 400-520 ms, mediated by the parahippocampal region. The study indicates rapid serial processing of innate emotional quality, then cognitive-behavioral relevance of stimuli, mediated by limbic and paralimbic structures.
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Affiliation(s)
- Louis Nahum
- Department of Clinical Neurosciences, Division of Neurorehabilitation, University Hospitals and University of Geneva, Switzerland
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40
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Three sequential brain activations encode mental transformations of upright and inverted human bodies: A high resolution evoked potential study. Neuroscience 2009; 159:1316-25. [DOI: 10.1016/j.neuroscience.2009.02.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2008] [Revised: 02/02/2009] [Accepted: 02/04/2009] [Indexed: 11/20/2022]
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41
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The incidence and determinants of visual phenomenology during out-of-body experiences. Cortex 2009; 45:236-42. [DOI: 10.1016/j.cortex.2007.06.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Revised: 04/03/2007] [Accepted: 06/12/2007] [Indexed: 01/18/2023]
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42
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Easton S, Blanke O, Mohr C. A putative implication for fronto-parietal connectivity in out-of-body experiences. Cortex 2009; 45:216-27. [DOI: 10.1016/j.cortex.2007.07.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2006] [Revised: 07/13/2007] [Accepted: 07/23/2007] [Indexed: 11/30/2022]
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43
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A Cognitive Neuroscience View of Schizophrenic Symptoms: Abnormal Activation of a System for Social Perception and Communication. Brain Imaging Behav 2008; 3:85-110. [PMID: 19809534 PMCID: PMC2757313 DOI: 10.1007/s11682-008-9052-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We will review converging evidence that language related symptoms of the schizophrenic syndrome such as auditory verbal hallucinations arise at least in part from processing abnormalities in posterior language regions. These language regions are either adjacent to or overlapping with regions in the (posterior) temporal cortex and temporo-parietal occipital junction that are part of a system for processing social cognition, emotion, and self representation or agency. The inferior parietal and posterior superior temporal regions contain multi-modal representational systems that may also provide rapid feedback and feed-forward activation to unimodal regions such as auditory cortex. We propose that the over-activation of these regions could not only result in erroneous activation of semantic and speech (auditory word) representations, resulting in thought disorder and voice hallucinations, but could also result in many of the other symptoms of schizophrenia. These regions are also part of the so-called “default network”, a network of regions that are normally active; and their activity is also correlated with activity within the hippocampal system.
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44
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Self in time: imagined self-location influences neural activity related to mental time travel. J Neurosci 2008; 28:6502-7. [PMID: 18562621 DOI: 10.1523/jneurosci.5712-07.2008] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Conscious awareness of the self as continuous through time is attributed to the human ability to remember the past and to predict the future, a cogitation that has been called "mental time travel" (MTT). MTT allows one to re-experience one's own past by subjectively "locating" the self to a previously experienced place and time, or to pre-experience an event by locating the self into the future. Here, we used a novel behavioral paradigm in combination with evoked potential mapping and electrical neuroimaging, revealing that MTT is composed of two different cognitive processes: absolute MTT, which is the location of the self to different points in time (past, present, or future), and relative MTT, which is the location of one's self with respect to the experienced event (relative past and relative future). These processes recruit a network of brain areas in distinct time periods including the occipitotemporal, temporoparietal, and anteromedial temporal cortices. Our findings suggest that in addition to autobiographical memory processes, the cognitive mechanisms of MTT also involve mental imagery and self-location, and that relative MTT, but not absolute MTT, is more strongly directed to future prediction than to past recollection.
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45
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Mégevand P, Quairiaux C, Lascano AM, Kiss JZ, Michel CM. A mouse model for studying large-scale neuronal networks using EEG mapping techniques. Neuroimage 2008; 42:591-602. [PMID: 18585931 DOI: 10.1016/j.neuroimage.2008.05.016] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 04/17/2008] [Accepted: 05/07/2008] [Indexed: 11/15/2022] Open
Abstract
Human functional imaging studies are increasingly focusing on the identification of large-scale neuronal networks, their temporal properties, their development, and their plasticity and recovery after brain lesions. A method targeting large-scale networks in rodents would open the possibility to investigate their neuronal and molecular basis in detail. We here present a method to study such networks in mice with minimal invasiveness, based on the simultaneous recording of epicranial EEG from 32 electrodes regularly distributed over the head surface. Spatiotemporal analysis of the electrical potential maps similar to human EEG imaging studies allows quantifying the dynamics of the global neuronal activation with sub-millisecond resolution. We tested the feasibility, stability and reproducibility of the method by recording the electrical activity evoked by mechanical stimulation of the mystacial vibrissae. We found a series of potential maps with different spatial configurations that suggested the activation of a large-scale network with generators in several somatosensory and motor areas of both hemispheres. The spatiotemporal activation pattern was stable both across mice and in the same mouse across time. We also performed 16-channel intracortical recordings of the local field potential across cortical layers in different brain areas and found tight spatiotemporal concordance with the generators estimated from the epicranial maps. Epicranial EEG mapping thus allows assessing sensory processing by large-scale neuronal networks in living mice with minimal invasiveness, complementing existing approaches to study the neurophysiological mechanisms of interaction within the network in detail and to characterize their developmental, experience-dependent and lesion-induced plasticity in normal and transgenic animals.
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Affiliation(s)
- Pierre Mégevand
- Fundamental Neuroscience Department, Geneva University Medical School, Rue Michel-Servet 1, 1211 Geneva 14, Switzerland
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Murray MM, Brunet D, Michel CM. Topographic ERP analyses: a step-by-step tutorial review. Brain Topogr 2008; 20:249-64. [PMID: 18347966 DOI: 10.1007/s10548-008-0054-5] [Citation(s) in RCA: 757] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2008] [Accepted: 02/13/2008] [Indexed: 11/29/2022]
Abstract
In this tutorial review, we detail both the rationale for as well as the implementation of a set of analyses of surface-recorded event-related potentials (ERPs) that uses the reference-free spatial (i.e. topographic) information available from high-density electrode montages to render statistical information concerning modulations in response strength, latency, and topography both between and within experimental conditions. In these and other ways these topographic analysis methods allow the experimenter to glean additional information and neurophysiologic interpretability beyond what is available from canonical waveform analyses. In this tutorial we present the example of somatosensory evoked potentials (SEPs) in response to stimulation of each hand to illustrate these points. For each step of these analyses, we provide the reader with both a conceptual and mathematical description of how the analysis is carried out, what it yields, and how to interpret its statistical outcome. We show that these topographic analysis methods are intuitive and easy-to-use approaches that can remove much of the guesswork often confronting ERP researchers and also assist in identifying the information contained within high-density ERP datasets.
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Affiliation(s)
- Micah M Murray
- Electroencephalography Brain Mapping Core, Center for Biomedical Imaging of Lausanne and Geneva, Radiologie CHUV BH08.078, Bugnon 46 Lausanne, Switzerland.
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Beyond Conventional Event-related Brain Potential (ERP): Exploring the Time-course of Visual Emotion Processing Using Topographic and Principal Component Analyses. Brain Topogr 2008; 20:265-77. [DOI: 10.1007/s10548-008-0053-6] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2007] [Accepted: 02/04/2008] [Indexed: 10/22/2022]
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