1
|
Li Z, Zhao S, Yang J, Murai T, Funahashi S, Wu J, Zhang Z. Is P3 amplitude associated with greater gaze distraction effect in schizotypy? Schizophr Res 2024; 267:422-431. [PMID: 38640853 DOI: 10.1016/j.schres.2024.04.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 02/27/2024] [Accepted: 04/03/2024] [Indexed: 04/21/2024]
Abstract
A recently proposed "Hyperfocusing hypothesis" suggests that schizotypy is associated with a more narrow but more intense way of allocating attention. The current study aims to test a vital prediction of this hypothesis in a social context, that schizotypy may be related to greater difficulty overcoming the distracting effects of gaze. This could cause a longer time to respond to targets that are invalidly cued by gaze. The current study tested this prediction in a modified Posner cueing paradigm by using P3 as an indicator for attentional resources. Seventy-four young healthy individuals with different levels of schizotypy were included, they were asked to detect the location of a target that was cued validly or invalidly by the gaze and head orientation. The results revealed that (a) schizotypy is associated with hyperfocusing on gaze direction, leading to greater difficulty overcoming the distracting effect of gaze. The higher the trait-schizotypy score, the more time needed to respond to targets that were invalidly cued by gaze (b) schizotypy is associated with reduced P3 which is directed by social communicative stimuli. The higher the trait-schizotypy score, the smaller the amplitude of P3 (c) the relationship between schizotypal traits and response times of the gaze-invalid condition is fully intermediated by P3. The findings of the current study suggest the P3 component may be a crucial neural mechanism underlying joint attention deficits in schizophrenia.
Collapse
Affiliation(s)
- Zimo Li
- Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, Japan; Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Shuo Zhao
- School of Psychology, ShenZhen University, ShenZhen, GuangDong, China.
| | - Jiajia Yang
- Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, Japan
| | - Toshiya Murai
- Department of Psychiatry, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Shintaro Funahashi
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Jinglong Wu
- Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, Japan; Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Zhilin Zhang
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China; Department of Psychiatry, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
| |
Collapse
|
2
|
Li J, Zhong BL, Zhou D, Fu Y, Huang X, Chen L, Liu H, Zheng J, Tang E, Li Y, Guan C, Shen M, Chen H. The dynamic process of hyperfocusing and hyperfiltering in schizophrenia. NATURE MENTAL HEALTH 2024; 2:367-378. [DOI: 10.1038/s44220-024-00211-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 01/24/2024] [Indexed: 08/01/2024]
|
3
|
Ronconi L, Florio V, Bronzoni S, Salvetti B, Raponi A, Giupponi G, Conca A, Basso D. Wider and Stronger Inhibitory Ring of the Attentional Focus in Schizophrenia. Brain Sci 2023; 13:brainsci13020211. [PMID: 36831754 PMCID: PMC9954763 DOI: 10.3390/brainsci13020211] [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: 12/15/2022] [Revised: 01/17/2023] [Accepted: 01/24/2023] [Indexed: 01/31/2023] Open
Abstract
Anomalies of attentional selection have been repeatedly described in individuals with schizophrenia spectrum disorders. However, a precise analysis of their ability to inhibit irrelevant visual information during attentional selection is not documented. Recent behavioral as well as neurophysiological and computational evidence showed that attentional search among different competing stimuli elicits an area of suppression in the immediate surrounding of the attentional focus. In the present study, the strength and spatial extension of this surround suppression were tested in individuals with schizophrenia and neurotypical controls. Participants were asked to report the orientation of a visual "pop-out" target, which appeared in different positions within a peripheral array of non-target stimuli. In half of the trials, after the target appeared, a probe circle circumscribed a non-target stimulus at various target-to-probe distances; in this case, participants were asked to report the probe orientation instead. Results suggest that, as compared to neurotypical controls, individuals with schizophrenia showed stronger and spatially more extended filtering of visual information in the areas surrounding their attentional focus. This increased filtering of visual information outside the focus of attention might potentially hamper their ability to integrate different elements into coherent percepts and influence higher order behavioral, affective, and cognitive domains.
Collapse
Affiliation(s)
- Luca Ronconi
- School of Psychology, Vita-Salute San Raffaele University, 20132 Milan, Italy
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132 Milan, Italy
- Correspondence:
| | - Vincenzo Florio
- Psychiatric Service of the Health District of Bozen, 39100 Bozen, Italy
| | - Silvia Bronzoni
- Psychiatric Service of the Health District of Bozen, 39100 Bozen, Italy
| | - Beatrice Salvetti
- Psychiatric Service of the Health District of Bozen, 39100 Bozen, Italy
| | - Agnese Raponi
- Psychiatric Service of the Health District of Bozen, 39100 Bozen, Italy
| | | | - Andreas Conca
- Psychiatric Service of the Health District of Bozen, 39100 Bozen, Italy
| | - Demis Basso
- CESLab, Faculty of Education, Free University of Bozen, 39042 Brixen, Italy
- Centro de Investigación en Neuropsicologia y Neurociencias Cognitivas (CINPSI Neurocog), Universidad Católica del Maule, Av. San Miguel, Talca 3480094, Chile
| |
Collapse
|
4
|
Reavis EA, Wynn JK, Green MF. The flickering spotlight of visual attention: Characterizing abnormal object-based attention in schizophrenia. Schizophr Res 2022; 248:151-157. [PMID: 36063606 PMCID: PMC10362949 DOI: 10.1016/j.schres.2022.08.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 07/22/2022] [Accepted: 08/21/2022] [Indexed: 10/14/2022]
Abstract
Schizophrenia is associated with deficits in both object perception and visual attention. However, few studies in schizophrenia have investigated object-based attention, which is dissociable from other forms of visuospatial attention. Recent research in healthy populations has shown that the 'spotlight' of sustained visual attention flickers in a rhythmic, oscillatory fashion at specific frequencies in the 4-12 Hz range. In healthy samples, this oscillatory signature has been used to investigate spatiotemporal dynamics of object-based attention, showing that the attentional spotlight spreads to uncued locations within cued objects, and also periodically alternates focus between cued and uncued objects. In this study, we adapted a performance-based visual object cueing task to investigate object-based attention in individuals with a schizophrenia diagnosis and healthy controls. In controls, spatiotemporal patterns of object-based attention closely resembled those reported in previous studies of healthy individuals. In the schizophrenia group, the oscillatory signature of attention also appeared in the location of the cue and on uncued objects, similar to the effects in controls. Indeed, the oscillatory signature of attention at the spatial location of the cue was stronger in the schizophrenia group than in controls. However, attention did not spread across the cued object in schizophrenia; rather, attention appeared to remain hyperfocused at the spatial location of the cue. These findings provide the first evidence that visual attention has oscillatory characteristics in schizophrenia, as in the general population. The results also show that the fundamental process of attentional spreading which underlies object-based attention is abnormal in schizophrenia.
Collapse
Affiliation(s)
- Eric A Reavis
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, United States of America; VA Greater Los Angeles Healthcare System, United States of America.
| | - Jonathan K Wynn
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, United States of America; VA Greater Los Angeles Healthcare System, United States of America
| | - Michael F Green
- Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, United States of America; VA Greater Los Angeles Healthcare System, United States of America
| |
Collapse
|
5
|
Abstract
Attention is clearly a core area of cognitive dysfunction in schizophrenia, but the concept of "attention" is complex and multifaceted. This chapter focuses on three different aspects of attentional function that are of particular interest in schizophrenia. First, we discuss the evidence that schizophrenia involves a reduction in global alertness, leading to an inward focusing of attention and a neglect of external stimuli and tasks. Second, we discuss the control of attention, the set of processes that allow general goals to be translated into shifts of attention toward task-relevant information. When a goal is adequately represented, people with schizophrenia often show no deficit in using the goal to direct attention in the visual modality unless challenged by stimuli that strongly activate the magnocellular processing pathway. Finally, we discuss the implementation of selection, the processes that boost relevant information and suppress distractors once attention has been directed to a given source of information. Although early evidence indicated an impairment in selection, more recent evidence indicating that people with schizophrenia actually focus their attention more narrowly and more intensely that healthy individuals (hyperfocusing). However, this hyperfocused attention may be directed toward goal-irrelevant information, creating the appearance of impaired attentional filtering.
Collapse
Affiliation(s)
- Steven J Luck
- Department of Psychology, Center for Mind and Brain, University of California, Davis, CA, USA.
| | - James M Gold
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, USA
| |
Collapse
|
6
|
Kınıklıoğlu M, Boyaci H. Increasing the spatial extent of attention strengthens surround suppression. Vision Res 2022; 199:108074. [PMID: 35717748 DOI: 10.1016/j.visres.2022.108074] [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: 11/29/2021] [Revised: 04/20/2022] [Accepted: 04/27/2022] [Indexed: 10/18/2022]
Abstract
Here we investigate how the extent of spatial attention affects center-surround interaction in visual motion processing. To do so, we measured motion direction discrimination thresholds in humans using drifting gratings and two attention conditions. Participants were instructed to limit their attention to the central part of the stimulus under the narrow attention condition, and to both central and surround parts under the wide attention condition. We found stronger surround suppression under the wide attention condition. The magnitude of the attention effect increased with the size of the surround when the stimulus had low contrast, but did not change when it had high contrast. Results also showed that attention had a weaker effect when the center and surround gratings drifted in opposite directions. Next, to establish a link between the behavioral results and the neuronal response characteristics, we performed computer simulations using the divisive normalization model. Our simulations showed that using smaller versus larger multiplicative attentional gain and parameters derived from the medial temporal (MT) area of the cortex, the model can successfully predict the observed behavioral results. These findings reveal the critical role of spatial attention on surround suppression and establish a link between neuronal activity and behavior. Further, these results also suggest that the reduced surround suppression found in certain clinical disorders (e.g., schizophrenia and autism spectrum disorder) may be caused by abnormal attention mechanisms.
Collapse
Affiliation(s)
- Merve Kınıklıoğlu
- Interdisciplinary Neuroscience Program, Bilkent University, Ankara 06800, Turkey; Aysel Sabuncu Brain Research Center & National Magnetic Resonance Research Center (UMRAM), Bilkent University, Ankara 06800, Turkey.
| | - Huseyin Boyaci
- Interdisciplinary Neuroscience Program, Bilkent University, Ankara 06800, Turkey; Aysel Sabuncu Brain Research Center & National Magnetic Resonance Research Center (UMRAM), Bilkent University, Ankara 06800, Turkey; Department of Psychology, Bilkent University, Ankara 06800, Turkey; Department of Psychology, Justus Liebig University Giessen, Giessen, Germany.
| |
Collapse
|
7
|
Lack of neural load modulation explains attention and working memory deficits in first-episode schizophrenia. Clin Neurophysiol 2022; 136:206-218. [DOI: 10.1016/j.clinph.2022.02.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 01/29/2022] [Accepted: 02/02/2022] [Indexed: 11/23/2022]
|
8
|
Zhao YJ, Ma T, Zhang L, Ran X, Zhang RY, Ku Y. Atypically larger variability of resource allocation accounts for visual working memory deficits in schizophrenia. PLoS Comput Biol 2021; 17:e1009544. [PMID: 34748538 PMCID: PMC8601612 DOI: 10.1371/journal.pcbi.1009544] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 11/18/2021] [Accepted: 10/07/2021] [Indexed: 11/18/2022] Open
Abstract
Working memory (WM) deficits have been widely documented in schizophrenia (SZ), and almost all existing studies attributed the deficits to decreased capacity as compared to healthy control (HC) subjects. Recent developments in WM research suggest that other components, such as precision, also mediate behavioral performance. It remains unclear how different WM components jointly contribute to deficits in schizophrenia. We measured the performance of 60 SZ (31 females) and 61 HC (29 females) in a classical delay-estimation visual working memory (VWM) task and evaluated several influential computational models proposed in basic science of VWM to disentangle the effect of various memory components. We show that the model assuming variable precision (VP) across items and trials is the best model to explain the performance of both groups. According to the VP model, SZ exhibited abnormally larger variability of allocating memory resources rather than resources or capacity per se. Finally, individual differences in the resource allocation variability predicted variation of symptom severity in SZ, highlighting its functional relevance to schizophrenic pathology. This finding was further verified using distinct visual features and subject cohorts. These results provide an alternative view instead of the widely accepted decreased-capacity theory and highlight the key role of elevated resource allocation variability in generating atypical VWM behavior in schizophrenia. Our findings also shed new light on the utility of Bayesian observer models to characterize mechanisms of mental deficits in clinical neuroscience. Working memory is a core cognitive function related to a broad range of cognitive domains such as problem-solving, attention, executive control, and IQ. Although working memory deficits have been well-documented in schizophrenia, the underlying mechanisms remain unclear. Conventional working memory theories attribute working memory deficits in schizophrenia to their reduced memory capacity, overlooking the potential roles of other memory components, such as precision. In this study, we take the approach of computational psychiatry and use computational modeling to uncover the major determinants of working memory deficits. We assess working memory performance of a large cohort of participants (60 schizophrenia patients and 61 demographic matched healthy controls) and evaluate multiple mainstream computational models of visual working memory. The variable precision model turns out to be the best model for both groups. We further find that the poorer performance of schizophrenia patients arises from heterogeneous distribution of memory resources when encoding items in memory. This resource allocation variability can also predict symptom severity in schizophrenia. Our study highlights the use of computational models in psychiatric researches.
Collapse
Affiliation(s)
- Yi-Jie Zhao
- Center for Brain and Mental Well-being, Department of Psychology, Sun Yat-sen University, Guangzhou, China
- Peng Cheng Laboratory, Shenzhen, China
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
- School of Psychology and Cognitive Science, East China Normal University, Shanghai, China
| | - Tianye Ma
- School of Psychology and Cognitive Science, East China Normal University, Shanghai, China
| | - Li Zhang
- Shanghai Changning Mental Health Center, Shanghai, China
| | - Xuemei Ran
- School of Psychology and Cognitive Science, East China Normal University, Shanghai, China
| | - Ru-Yuan Zhang
- Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Institute of Psychology and Behavioral Science, Antai College of Economics and Management, Shanghai Jiao Tong University, Shanghai, China
- * E-mail: (R-YZ); (YK)
| | - Yixuan Ku
- Center for Brain and Mental Well-being, Department of Psychology, Sun Yat-sen University, Guangzhou, China
- Peng Cheng Laboratory, Shenzhen, China
- * E-mail: (R-YZ); (YK)
| |
Collapse
|
9
|
Hahn B, Robinson BM, Kiat JE, Geng J, Bansal S, Luck SJ, Gold JM. Impaired Filtering and Hyperfocusing: Neural Evidence for Distinct Selective Attention Abnormalities in People with Schizophrenia. Cereb Cortex 2021; 32:1950-1964. [PMID: 34546344 DOI: 10.1093/cercor/bhab327] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Although schizophrenia is classically thought to involve impaired attentional filtering, people with schizophrenia (PSZ) exhibit a more intense and more exclusive attentional focus than healthy control subjects (HCS) in many tasks. To resolve this contradiction, this functional magnetic resonance imaging study tested the impact of attentional control demands on the modulation of stimulus-induced activation in the fusiform face area and parahippocampal place area when participants (43 PSZ and 43 HCS) were looking for a target face versus house. Stimuli were presented individually, or as face-house overlays that challenged attentional control. Responses were slower for house than face stimuli and when prioritizing houses over faces in overlays, suggesting a difference in salience. Blood-oxygen-level-dependent activity reflected poorer attentional selectivity in PSZ than HCS when attentional control was challenged most, that is, when stimuli were overlaid and the task required detecting the lower-salience house target. By contrast, attentional selectivity was exaggerated in PSZ when control was challenged least, that is, when stimuli were presented sequentially and the task required detecting the higher-salience face target. These findings are consistent with 2 distinct attentional abnormalities in schizophrenia leading to impaired and exaggerated selection under different conditions: attentional control deficits, and hyperfocusing once attention has been directed toward a stimulus.
Collapse
Affiliation(s)
- Britta Hahn
- University of Maryland School of Medicine, Maryland Psychiatric Research Center, Baltimore, MD 21228, USA
| | - Benjamin M Robinson
- University of Maryland School of Medicine, Maryland Psychiatric Research Center, Baltimore, MD 21228, USA
| | - John E Kiat
- University of California Davis, Center for Mind and Brain, Davis, CA 95618, USA
| | - Joy Geng
- University of California Davis, Center for Mind and Brain, Davis, CA 95618, USA
| | - Sonia Bansal
- University of Maryland School of Medicine, Maryland Psychiatric Research Center, Baltimore, MD 21228, USA
| | - Steven J Luck
- University of California Davis, Center for Mind and Brain, Davis, CA 95618, USA
| | - James M Gold
- University of Maryland School of Medicine, Maryland Psychiatric Research Center, Baltimore, MD 21228, USA
| |
Collapse
|
10
|
Bansal S, Gaspelin N, Robinson BM, Hahn B, Luck SJ, Gold JM. Oculomotor inhibition and location priming in schizophrenia. JOURNAL OF ABNORMAL PSYCHOLOGY 2021; 130:651-664. [PMID: 34553960 PMCID: PMC8480515 DOI: 10.1037/abn0000683] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Schizophrenia is widely thought to involve elevated distractibility, which may reflect a general impairment in top-down inhibitory processes. Schizophrenia also appears to involve increased priming of previously performed actions. Here, we used a highly refined eye-tracking paradigm that makes it possible to concurrently assess distractibility, inhibition, and priming. In both healthy control subjects (HCS, N = 41) and people with schizophrenia (PSZ, N = 46), we found that initial saccades were actually less likely to be directed toward a salient "singleton" distractor than toward less salient distractors, reflecting top-down suppression of the singleton. Remarkably, this oculomotor suppression effect was as strong or stronger in PSZ than in HCS, indicating intact inhibitory control. In addition, saccades were frequently directed to the location of the previous-trial target in both groups, but this priming effect was much stronger in PSZ than in HCS. Indeed, PSZ directed gaze toward the location of the previous-trial target as often as they directed gaze to the location of the current-trial target. These results demonstrate that-at least in the context of visual search-PSZ are no more distractable than HCS and are fully capable of inhibiting salient-but-irrelevant stimuli. However, PSZ do exhibit exaggerated priming, focusing on recently attended locations even when this is not beneficial for goal attainment. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
Collapse
Affiliation(s)
- Sonia Bansal
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine
| | - Nicholas Gaspelin
- Department of Psychology, Binghamton University, State University of New York
| | - Benjamin M. Robinson
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine
| | - Britta Hahn
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine
| | - Steven J. Luck
- Center for Mind & Brain and Department of Psychology, University of California, Davis
| | - James M. Gold
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine
| |
Collapse
|
11
|
Sardari S, Pourrahimi A, Fathi M, Talebi H, Mazhari S. Auditory processing in schizophrenia: Behavioural evidence of abnormal spatial awareness. Laterality 2021; 27:71-85. [PMID: 34293997 DOI: 10.1080/1357650x.2021.1955910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Spatial processing deficits are the reason for many daily life problems of schizophrenia (SCZ) patients. In this study, we aimed to examine the possibility of abnormal bias to one hemifield, in form of hemispatial neglect and extinction, in auditory modality in SCZ. Twenty-five SCZ patients and 25 healthy individuals were compared on speech tasks to study the auditory neglect and extinction, as well as an auditory localization task for studying neglect. In the speech tasks, participants reproduced some nonsense syllables, played from one or two speakers on the right and/or left sides. On the localization task, examinees discriminated the subjective location of the noise stimuli presented randomly from five speakers. On the speech task, patients had significantly lower hit rates for the right ear compared with controls (p = 0.01). While healthy controls showed right ear advantage, SCZs showed a left ear priority. In the localization task, although both groups had a left-side bias, this bias was much more prominent for the patients (all p < 0.05). SCZ could potentially alter the auditory spatial function, which may appear in the form of auditory neglect and extinction on the right side, depending on the characteristics of patient population.
Collapse
Affiliation(s)
- Sara Sardari
- Kerman Neuroscience Research center, Kerman University of Medical Sciences, Kerman, Iran
| | - AliMohammad Pourrahimi
- Kerman Neuroscience Research center, Kerman University of Medical Sciences, Kerman, Iran
| | - Mazyar Fathi
- Kerman Neuroscience Research center, Kerman University of Medical Sciences, Kerman, Iran
| | - Hosein Talebi
- Audiology department, Rehabilitation faculty, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Shahrzad Mazhari
- Kerman Neuroscience Research center, Kerman University of Medical Sciences, Kerman, Iran.,Department of Psychiatry, Medical School, Kerman University of Medical Sciences, Kerman, Iran
| |
Collapse
|
12
|
Ashinoff BK, Abu-Akel A. Hyperfocus: the forgotten frontier of attention. PSYCHOLOGICAL RESEARCH 2021; 85:1-19. [PMID: 31541305 PMCID: PMC7851038 DOI: 10.1007/s00426-019-01245-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 09/09/2019] [Indexed: 01/20/2023]
Abstract
'Hyperfocus' is a phenomenon that reflects one's complete absorption in a task, to a point where a person appears to completely ignore or 'tune out' everything else. Hyperfocus is most often mentioned in the context of autism, schizophrenia, and attention deficit hyperactivity disorder, but research into its effect on cognitive and neural functioning is limited. We propose that hyperfocus is a critically important aspect of cognition, particularly with regard to clinical populations, and that it warrants significant investigation. Hyperfocus, though ostensibly self-explanatory, is poorly defined within the literature. In many cases, hyperfocus goes undefined, relying on the assumption that the reader inherently knows what it entails. Thus, there is no single consensus to what constitutes hyperfocus. Moreover, some studies do not refer to hyperfocus by name, but describe processes that may be related. In this paper, we review how hyperfocus (as well as possibly related phenomena) has been defined and measured, the challenges associated with hyperfocus research, and assess how hyperfocus affects both neurotypical and clinical populations. Using this foundation, we provide constructive criticism about previously used methods and analyses. We also propose an operational definition of hyperfocus for researchers to use moving forward.
Collapse
Affiliation(s)
- Brandon K Ashinoff
- Department of Psychiatry, Columbia University, 1051 Riverside Dr, New York, NY, 10032, USA.
- Centre for Human Brain Health (CHBH), School of Psychology, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.
| | - Ahmad Abu-Akel
- Institute of Psychology, University of Lausanne, Quartier UNIL-Mouline, Geopolis, Lausanne, 1015, Switzerland
| |
Collapse
|
13
|
Griffiths O, Balzan R. Schizotypy is associated with difficulty maintaining multiple hypotheses. Q J Exp Psychol (Hove) 2021; 74:1153-1163. [PMID: 33283637 DOI: 10.1177/1747021820982256] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Among neurocognitive accounts of delusions, there is a growing consensus that it is the certainty with which delusions are held, rather than their content that defines some beliefs as delusional. On a continuum model of psychosis, this inappropriate certainty ought to be present (albeit in an attenuated form) in healthy adults who score highly in schizotypy. It was hypothesised that this might be most evident in circumstances where the environment provides incomplete or probabilistic information, which thereby forces the participant to hold two imperfectly supported, concurrent hypotheses in mind. A cued visual search task was used to measure people's capacity to use partially predictive information (i.e., a cue that predicted the target may occur in one of the two locations) to facilitate speeded responding. As hypothesised, people's performance on the trials that required holding two hypotheses in mind concurrently was significantly and specifically associated with the positive components of schizotypy. This finding is consistent with a hyperfocusing of attention in schizophrenia, and may help explain why delusion-prone individuals have a tendency to "jump to conclusions" or be resistant to disconfirming information when faced with multiple, partially supported hypotheses.
Collapse
Affiliation(s)
- Oren Griffiths
- Discipline of Psychology, Flinders University, Adelaide, SA, Australia
| | - Ryan Balzan
- Discipline of Psychology, Flinders University, Adelaide, SA, Australia
| |
Collapse
|
14
|
Coffman BA, Murphy TK, Haas G, Olson C, Cho R, Ghuman AS, Salisbury DF. Lateralized evoked responses in parietal cortex demonstrate visual short-term memory deficits in first-episode schizophrenia. J Psychiatr Res 2020; 130:292-299. [PMID: 32866678 PMCID: PMC7554220 DOI: 10.1016/j.jpsychires.2020.07.036] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 07/25/2020] [Accepted: 07/25/2020] [Indexed: 11/19/2022]
Abstract
Working memory dysfunction may be central to neurocognitive deficits in schizophrenia. Maintenance of visual information in working memory, or visual short-term memory (vSTM), is linked to general cognitive dysfunction and predicts functional outcome. Lateralized change-detection tasks afford investigation of the contralateral delay activity (CDA), a useful tool for investigating vSTM dysfunction. Previous work suggests "hyperfocusing" of attention in schizophrenia, such that CDA is increased when a single item is maintained in vSTM but reduced for multiple items. If observed early in the disease, vSTM dysfunction may be a key feature of schizophrenia or target for intervention. We investigated CDA during lateralized vSTM of one versus three items using sensor-level electroencephalography and source-level magnetoencephalography in 26 individuals at their first episode of schizophrenia-spectrum psychosis (FESz) and 26 matched healthy controls. FESz were unable to modulate CDA with increased memory load - high-load CDA was reduced and low-load CDA was increased compared to controls. Further, sources of CDA in posterior parietal cortex were reduced in FESz and indices of working memory were correlated with neurocognitive deficits and symptom severity. These results support working memory maintenance dysfunction as a central and early component to the disorder. Targeted intervention focusing on vSTM deficits may be warranted to alleviate downstream effects of this disability.
Collapse
Affiliation(s)
- Brian A Coffman
- Clinical Neurophysiology Research Laboratory, Western Psychiatric Hospital of UPMC, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Tim K Murphy
- Clinical Neurophysiology Research Laboratory, Western Psychiatric Hospital of UPMC, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Gretchen Haas
- Western Psychiatric Hospital of UPMC, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Carl Olson
- Center for Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Raymond Cho
- Western Psychiatric Hospital of UPMC, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA; Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, Houston, TX, USA; Michael E. DeBakey Houston VA Medical Center, Houston, TX, USA
| | - Avniel Singh Ghuman
- Laboratory of Cognitive Neurodynamics, Department of Neurosurgery, Presbyterian Hospital, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Dean F Salisbury
- Clinical Neurophysiology Research Laboratory, Western Psychiatric Hospital of UPMC, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
| |
Collapse
|
15
|
Coffman BA, Haas G, Olson C, Cho R, Ghuman AS, Salisbury DF. Reduced Dorsal Visual Oscillatory Activity During Working Memory Maintenance in the First-Episode Schizophrenia Spectrum. Front Psychiatry 2020; 11:743. [PMID: 32848922 PMCID: PMC7417606 DOI: 10.3389/fpsyt.2020.00743] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 07/16/2020] [Indexed: 11/17/2022] Open
Abstract
Cognitive deficits in people with schizophrenia are among the hardest to treat and strongly predict functional outcome. The ability to maintain sensory precepts in memory over a short delay is impacted early in the progression of schizophrenia and has been linked to reliable neurophysiological markers. Yet, little is known about the mechanisms of these deficits. Here, we investigated possible neurophysiological mechanisms of impaired visual short-term memory (vSTM, aka working memory maintenance) in the first-episode schizophrenia spectrum (FESz) using magnetoencephalography (MEG). Twenty-eight FESz and 25 matched controls performed a lateralized change detection task where they were cued to selectively attend and remember colors of circles presented in either the left or right peripheral visual field over a 1 s delay. Contralateral alpha suppression (CAS) during the delay period was used to assess selective attention to cued visual hemifields held in vSTM. Delay-period CAS was compared between FESz and controls and between trials presenting one vs three items per visual hemifield. CAS in dorsal visual cortex was reduced in FESz compared to controls in high-load trials, but not low-load trials. Group differences in CAS were found beginning 100 ms after the disappearance of the memory set, suggesting deficits were not due to the initial deployment of attention to the cued visual hemifield prior to stimulus presentation. CAS was not greater for high-load vs low-load trials in FESz subjects, although this effect was prominent in controls. Further, lateralized gamma (34-40 Hz) power emerged in dorsal visual cortex prior to the onset of CAS in controls but not FESz. Gamma power in this cluster differed between groups at both high and low load. CAS deficits observed in FESz were correlated with change detection accuracy, working memory function, estimated IQ, and negative symptoms. Our results implicate deficits in CAS in trials requiring broad, but not narrow, focus of attention to spatially distributed objects maintained in vSTM in FESz, possibly due to reduced ability to broadly distribute visuospatial attention (alpha) or disruption of object-location binding (gamma) during encoding/consolidation. This early pathophysiology may shed light upon mechanisms of emerging working memory deficits that are intrinsic to schizophrenia.
Collapse
Affiliation(s)
- Brian A. Coffman
- Clinical Neurophysiology Research Laboratory, Western Psychiatric Hospital of UPMC, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Gretchen Haas
- Western Psychiatric Hospital of UPMC, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Carl Olson
- Center for Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, PA, United States
| | - Raymond Cho
- Western Psychiatric Hospital of UPMC, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
- Department of Psychiatry and Behavioral Sciences, Baylor College of Medicine, Houston, TX, United States
| | - Avniel Singh Ghuman
- Laboratory of Cognitive Neurodynamics, Department of Neurosurgery, Presbyterian Hospital, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Dean F. Salisbury
- Clinical Neurophysiology Research Laboratory, Western Psychiatric Hospital of UPMC, Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| |
Collapse
|
16
|
Lin YX, Zhang LJ, Ying L, Zhou Q. Cognitive effort-avoidance in patients with schizophrenia can reflect Amotivation: an event-related potential study. BMC Psychiatry 2020; 20:344. [PMID: 32611333 PMCID: PMC7329480 DOI: 10.1186/s12888-020-02744-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 06/19/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Amotivation is regarded as a core negative symptom in patients with schizophrenia. There are currently no objective methods for assessing and measuring amotivation in the scientific literature, only a trend towards assessing motivation using effort-orientated, decision-making tasks. However, it remains inconclusive as to whether cognitive effort-avoidance in patients with schizophrenia can reflect their amotivation. Therefore, this study aimed to find out whether cognitive effort-avoidance in patients with schizophrenia can reflect their amotivation. METHODS In total, 28 patients with schizophrenia and 27 healthy controls were selected as participants. The demand selection task (DST) was adapted according to the feedback-based Guilty Knowledge Test (GKT) delayed response paradigm, which was combined with the mean amplitude of contingent negative variation (CNV), considered as the criterion of motivation. RESULTS Our results showed that: (1) patients with schizophrenia showed a lower CNV amplitude for the target stimuli compared to the probe stimuli, whereas the control group showed the opposite trend (P < 0.05); (2) among patients with schizophrenia, the high cognitive effort-avoidance group showed a smaller CNV amplitude for the target stimuli compared to the probe stimuli, whereas the low cognitive effort avoidance group showed a higher CNV amplitude for the target stimuli compared to the probe stimuli; the opposite trend was observed in the control group (P < 0.05). CONCLUSION These findings support the claim that CNV amplitude can be used as a criterion for detecting amotivation in patients with schizophrenia. Within the context of the DST, the high and low cognitive effort-avoidance of patients with schizophrenia can reflect their state of amotivation; patients with high cognitive effort-avoidance showed severe amotivation.
Collapse
Affiliation(s)
- Y. X. Lin
- grid.268099.c0000 0001 0348 3990Department of Psychology, Wenzhou Medical University, Chashan University Town, Chashan, Wenzhou, 325035 Zhejiang Province China
| | - Li Jun Zhang
- Psychiatric Rehabilitation, Wenzhou Seventh Hospital, Wenzhou, China
| | - Liang Ying
- grid.268099.c0000 0001 0348 3990Wenzhou Medical University, Wenzhou, China
| | - Qiang Zhou
- Department of Psychology, Wenzhou Medical University, Chashan University Town, Chashan, Wenzhou, 325035, Zhejiang Province, China.
| |
Collapse
|
17
|
Carment L, Dupin L, Guedj L, Térémetz M, Cuenca M, Krebs MO, Amado I, Maier MA, Lindberg PG. Neural noise and cortical inhibition in schizophrenia. Brain Stimul 2020; 13:1298-1304. [PMID: 32585356 DOI: 10.1016/j.brs.2020.06.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 05/25/2020] [Accepted: 06/14/2020] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Neural information processing is subject to noise and this leads to variability in neural firing and behavior. Schizophrenia has been associated with both more variable motor control and impaired cortical inhibition, which is crucial for excitatory/inhibitory balance in neural commands. HYPOTHESIS In this study, we hypothesized that impaired intracortical inhibition in motor cortex would contribute to task-related motor noise in schizophrenia. METHODS We measured variability of force and of electromyographic (EMG) activity in upper limb and hand muscles during a visuomotor grip force-tracking paradigm in patients with schizophrenia (N = 25), in unaffected siblings (N = 17) and in healthy control participants (N = 25). Task-dependent primary motor cortex (M1) excitability and inhibition were assessed using transcranial magnetic stimulation (TMS). RESULTS During force maintenance patients with schizophrenia showed increased variability in force and EMG, despite similar mean force and EMG magnitudes. Compared to healthy controls, patients with schizophrenia also showed increased M1 excitability and reduced cortical inhibition during grip-force tracking. EMG variability and force variability correlated negatively to cortical inhibition in patients with schizophrenia. EMG variability also correlated positively to negative symptoms. Siblings had similar variability and cortical inhibition compared to controls. Increased EMG and force variability indicate enhanced motor noise in schizophrenia, which relates to reduced motor cortex inhibition. CONCLUSION The findings suggest that excessive motor noise in schizophrenia may arise from an imbalance of M1 excitation/inhibition of GABAergic origin. Thus, higher motor noise may provide a useful marker of impaired cortical inhibition in schizophrenia.
Collapse
Affiliation(s)
- Loïc Carment
- Institute of Psychiatry and Neuroscience of Paris, INSERM U894, Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Institut de Psychiatrie, CNRS, GDR3557, Paris, France.
| | - Lucile Dupin
- Institute of Psychiatry and Neuroscience of Paris, INSERM U894, Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Institut de Psychiatrie, CNRS, GDR3557, Paris, France
| | - Laura Guedj
- Resource Center for Cognitive Remediation and Psychosocial Rehabilitation, C3RP, Université de Paris, GHU Psychiatrie et Neurosciences Sainte-Anne, Paris, France
| | - Maxime Térémetz
- Institute of Psychiatry and Neuroscience of Paris, INSERM U894, Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Institut de Psychiatrie, CNRS, GDR3557, Paris, France
| | - Macarena Cuenca
- Institut de Psychiatrie, CNRS, GDR3557, Paris, France; Centre de Recherche Clinique, Hôpital Sainte-Anne, Paris, France
| | - Marie-Odile Krebs
- Institute of Psychiatry and Neuroscience of Paris, INSERM U894, Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Institut de Psychiatrie, CNRS, GDR3557, Paris, France; Resource Center for Cognitive Remediation and Psychosocial Rehabilitation, C3RP, Université de Paris, GHU Psychiatrie et Neurosciences Sainte-Anne, Paris, France
| | - Isabelle Amado
- Institute of Psychiatry and Neuroscience of Paris, INSERM U894, Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Institut de Psychiatrie, CNRS, GDR3557, Paris, France; Resource Center for Cognitive Remediation and Psychosocial Rehabilitation, C3RP, Université de Paris, GHU Psychiatrie et Neurosciences Sainte-Anne, Paris, France
| | - Marc A Maier
- Institut de Psychiatrie, CNRS, GDR3557, Paris, France; Université de Paris, CNRS UMR, 8002, Paris, France
| | - Påvel G Lindberg
- Institute of Psychiatry and Neuroscience of Paris, INSERM U894, Université Paris Descartes, Sorbonne Paris Cité, Paris, France; Institut de Psychiatrie, CNRS, GDR3557, Paris, France
| |
Collapse
|
18
|
Carment L, Dupin L, Guedj L, Térémetz M, Krebs MO, Cuenca M, Maier MA, Amado I, Lindberg PG. Impaired attentional modulation of sensorimotor control and cortical excitability in schizophrenia. Brain 2020; 142:2149-2164. [PMID: 31099820 PMCID: PMC6598624 DOI: 10.1093/brain/awz127] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 01/29/2019] [Accepted: 03/10/2019] [Indexed: 11/14/2022] Open
Abstract
Impairments in attentional, working memory and sensorimotor processing have been consistently reported in schizophrenia. However, the interaction between cognitive and sensorimotor impairments and the underlying neural mechanisms remains largely uncharted. We hypothesized that altered attentional processing in patients with schizophrenia, probed through saccadic inhibition, would partly explain impaired sensorimotor control and would be reflected as altered task-dependent modulation of cortical excitability and inhibition. Twenty-five stabilized patients with schizophrenia, 17 unaffected siblings and 25 healthy control subjects were recruited. Subjects performed visuomotor grip force-tracking alone (single-task condition) and with increased cognitive load (dual-task condition). In the dual-task condition, two types of trials were randomly presented: trials with visual distractors (requiring inhibition of saccades) or trials with addition of numbers (requiring saccades and addition). Both dual-task trial types required divided visual attention to the force-tracking target and to the distractor or number. Gaze was measured during force-tracking tasks, and task-dependent modulation of cortical excitability and inhibition were assessed using transcranial magnetic stimulation. In the single-task, patients with schizophrenia showed increased force-tracking error. In dual-task distraction trials, force-tracking error increased further in patients, but not in the other two groups. Patients inhibited fewer saccades to distractors, and the capacity to inhibit saccades explained group differences in force-tracking performance. Cortical excitability at rest was not different between groups and increased for all groups during single-task force-tracking, although, to a greater extent in patients (80%) compared to controls (40%). Compared to single-task force-tracking, the dual-task increased cortical excitability in control subjects, whereas patients showed decreased excitability. Again, the group differences in cortical excitability were no longer significant when failure to inhibit saccades was included as a covariate. Cortical inhibition was reduced in patients in all conditions, and only healthy controls increased inhibition in the dual-task. Siblings had similar force-tracking and gaze performance as controls but showed altered task-related modulation of cortical excitability and inhibition in dual-task conditions. In patients, neuropsychological scores of attention correlated with visuomotor performance and with task-dependant modulation of cortical excitability. Disorganization symptoms were greatest in patients with weakest task-dependent modulation of cortical excitability. This study provides insights into neurobiological mechanisms of impaired sensorimotor control in schizophrenia showing that deficient divided visual attention contributes to impaired visuomotor performance and is reflected in impaired modulation of cortical excitability and inhibition. In siblings, altered modulation of cortical excitability and inhibition is consistent with a genetic risk for cortical abnormality.
Collapse
Affiliation(s)
- Loïc Carment
- Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Institut de Psychiatrie, CNRS GDR3557, Paris, France
| | - Lucile Dupin
- Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Institut de Psychiatrie, CNRS GDR3557, Paris, France
| | - Laura Guedj
- SHU, Resource Center for Cognitive Remediation and Psychosocial Rehabilitation, Université Paris Descartes, Hôpital Sainte-Anne, Paris, France
| | - Maxime Térémetz
- Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Institut de Psychiatrie, CNRS GDR3557, Paris, France
| | - Marie-Odile Krebs
- Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Institut de Psychiatrie, CNRS GDR3557, Paris, France.,SHU, Resource Center for Cognitive Remediation and Psychosocial Rehabilitation, Université Paris Descartes, Hôpital Sainte-Anne, Paris, France
| | - Macarena Cuenca
- SHU, Resource Center for Cognitive Remediation and Psychosocial Rehabilitation, Université Paris Descartes, Hôpital Sainte-Anne, Paris, France.,Centre de Recherche Clinique, Hôpital Sainte-Anne, Paris, France.,Integrative Neuroscience and Cognition Center, UMR 8002, CNRS / Université Paris Descartes, Sorbonne Paris Cité, Paris, France
| | - Marc A Maier
- Institut de Psychiatrie, CNRS GDR3557, Paris, France.,Integrative Neuroscience and Cognition Center, UMR 8002, CNRS / Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Department of Life Sciences, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Isabelle Amado
- Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Institut de Psychiatrie, CNRS GDR3557, Paris, France.,SHU, Resource Center for Cognitive Remediation and Psychosocial Rehabilitation, Université Paris Descartes, Hôpital Sainte-Anne, Paris, France
| | - Påvel G Lindberg
- Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, Université Paris Descartes, Sorbonne Paris Cité, Paris, France.,Institut de Psychiatrie, CNRS GDR3557, Paris, France
| |
Collapse
|
19
|
Cortical hyperactivation at low working memory load: A primary processing abnormality in people with schizophrenia? NEUROIMAGE-CLINICAL 2020; 26:102270. [PMID: 32388334 PMCID: PMC7210598 DOI: 10.1016/j.nicl.2020.102270] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 04/01/2020] [Accepted: 04/20/2020] [Indexed: 11/20/2022]
Abstract
A frequent finding when studying substrates of working memory (WM) deficits in people with schizophrenia (PSZ) is task-induced hyperactivation relative to healthy control subjects (HCS) when WM load is low. Hyperactivation accompanying similar performance is commonly attributed to cognitive deficits rendering relatively easy operations more resource-consuming. To test if hyperactivation at low load really is secondary to cognitive impairment in PSZ, we re-analyzed functional MRI data showing left posterior parietal cortex (PPC) hyperactivation in PSZ when holding a single color-item in WM. In subgroups matched for the number of items successfully stored in WM (K) by excluding the highest-performing HCS and lowest-performing PSZ, performance was almost identical across all set sizes (1-7). While BOLD activation at the larger set sizes did not differ between groups, PSZ still robustly hyperactivated left PPC when a single item had to be maintained. The same pattern was observed in subgroups matched for model-based estimates of WM capacity or attentional lapse rate. Given that in the K-matched subsamples PSZ performed as well as HCS even in the most challenging load conditions and that no BOLD signal difference was seen at high loads, it is implausible that PSZ over-recruited WM-related neural structures because they were more challenged by maintaining a single item in WM. Instead, the findings are consistent with a primary schizophrenia-related processing abnormality as proposed by the hyperfocusing hypothesis, which suggests that an abnormally narrow but intense focusing of processing resources is central to many aspects of impaired cognition in PSZ.
Collapse
|
20
|
Gold JM, Bansal S, Gaspar JM, Chen S, Robinson BM, Hahn B, Luck SJ. People with schizophrenia show enhanced cognitive costs of maintaining a single item in working memory. Psychol Med 2020; 50:867-873. [PMID: 31088582 PMCID: PMC7112167 DOI: 10.1017/s0033291719000862] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Working memory (WM) deficits are seen as a core deficit in schizophrenia, implicated in the broad cognitive impairment seen in the illness. Here we examine the impact of WM storage of a single item on the operation of other cognitive systems. METHODS We studied 37 healthy controls (HCS) and 43 people with schizophrenia (PSZ). Each trial consisted of a sequence of two potential target stimuli, T1 and T2. T1 was a letter presented for 100 ms. After delays of 100-800 ms, T2 was presented. T2 was a 1 or a 2 and required a speeded response. In one condition, subjects were instructed to ignore T1 but respond to T2. In another condition, they were required to report T1 after making their speeded response to T2 (i.e. to make a speeded T2 response while holding T1 in WM). RESULTS PSZ were dramatically slowed at responding to T2 when T1 was held in WM. A repeated measures ANOVA yielded main effects of group, delay, and condition with a group by condition interaction (p's < 0.001). Across delays, the slowing of the T2 response when required to hold T1 in memory, relative to ignoring T1, was nearly 3 times higher in PSZ than HCS (633 v. 219 ms). CONCLUSIONS Whereas previous studies have focused on reduced storage capacity, the present study found that PSZ are impaired at performing tasks while they are successfully maintaining a single item in WM. This may play a role in the broad cognitive impairment seen in PSZ.
Collapse
Affiliation(s)
- James M Gold
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, USA
| | - Sonia Bansal
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, USA
| | - John M Gaspar
- Center for Mind & Brain and Department of Psychology, University of California Davis, Davis, USA
| | - Shuo Chen
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, USA
| | - Benjamin M Robinson
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, USA
| | - Britta Hahn
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, USA
| | - Steven J Luck
- Center for Mind & Brain and Department of Psychology, University of California Davis, Davis, USA
| |
Collapse
|
21
|
Bae GY, Leonard CJ, Hahn B, Gold JM, Luck SJ. Assessing the information content of ERP signals in schizophrenia using multivariate decoding methods. NEUROIMAGE-CLINICAL 2020; 25:102179. [PMID: 31954988 PMCID: PMC6965722 DOI: 10.1016/j.nicl.2020.102179] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 12/22/2019] [Accepted: 01/13/2020] [Indexed: 02/01/2023]
Abstract
This study took multivariate decoding methods that are widely used to assess the nature of neural representations in neurotypical people and applied them to a comparison of people with schizophrenia and matched control subjects. Participants performed a visual working memory task that required remembering 1–5 items from one side of the display and ignoring an equal number of items on the other side of the display. We attempted to decode which side was being held in working memory from the scalp distribution of the ERP activity during the delay period of the working memory task, and we found greater decoding accuracy in people with schizophrenia than in control subjects when a single item was being held in memory. These results support the hyperfocusing hypothesis of cognitive dysfunction in schizophrenia, and they provide an important proof of concept for applying multivariate decoding methods to comparisons of neural representations in psychiatric and non-psychiatric populations.
Multivariate pattern classification (decoding) methods are commonly employed to study mechanisms of neurocognitive processing in typical individuals, where they can be used to quantify the information that is present in single-participant neural signals. These decoding methods are also potentially valuable in determining how the representation of information differs between psychiatric and non-psychiatric populations. Here, we examined ERPs from people with schizophrenia (PSZ) and healthy control subjects (HCS) in a working memory task that involved remembering 1, 3, or 5 items from one side of the display and ignoring the other side. We used the spatial pattern of ERPs to decode which side of the display was being held in working memory. One might expect that decoding accuracy would be inevitably lower in PSZ as a result of increased noise (i.e., greater trial-to-trial variability). However, we found that decoding accuracy was greater in PSZ than in HCS at memory load 1, consistent with previous research in which memory-related ERP signals were larger in PSZ than in HCS at memory load 1. We also observed that decoding accuracy was strongly related to the ratio of the memory-related ERP activity and the noise level. In addition, we found similar noise levels in PSZ and HCS, counter to the expectation that PSZ would exhibit greater trial-to-trial variability. Together, these results demonstrate that multivariate decoding methods can be validly applied at the individual-participant level to understand the nature of impaired cognitive function in a psychiatric population.
Collapse
Affiliation(s)
- Gi-Yeul Bae
- Department of Psychology, Arizona State University, 950 S. McAllister Ave, Tempe, AZ 85287, USA.
| | - Carly J Leonard
- Department of Psychology, University of Colorado - Denver, USA
| | - Britta Hahn
- Maryland Psychiatric Research Center and School of Medicine, University of Maryland, USA
| | - James M Gold
- Maryland Psychiatric Research Center and School of Medicine, University of Maryland, USA
| | - Steven J Luck
- Center for Mind & Brain and Department of Psychology, University of California - Davis, USA
| |
Collapse
|
22
|
Sardari S, Pourrahimi AM, Talebi H, Mazhari S. Symmetrical electrophysiological brain responses to unilateral and bilateral auditory stimuli suggest disrupted spatial processing in schizophrenia. Sci Rep 2019; 9:16454. [PMID: 31712599 PMCID: PMC6848080 DOI: 10.1038/s41598-019-52931-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 10/26/2019] [Indexed: 11/08/2022] Open
Abstract
Research has found auditory spatial processing deficits in patients with schizophrenia (SCZ), but no study has examined SCZ patients' auditory spatial processing at both pre-attentional and attentional stages. To address this gap, we investigated schizophrenics' brain responses to sounds originating from different locations (right, left, and bilateral sources). The event-related potentials (ERPs) of 25 chronic schizophrenic patients and 25 healthy subjects were compared. Mismatch negativity (MMN) in response to frequency and duration deviants was assessed. Two P3 components (P3a and P3b) were elicited via a frequency discrimination task, and MMN and P3 were recorded through separate monaural and dichotic stimulation paradigms. Our results corroborated the previously published finding that MMN, P3a, and P3b amplitudes are reduced in SCZ patients, but they showed no significant effect of stimulus location on either MMN or P3. These results indicated similarity between the SCZ patients and healthy individuals as regards patterns of ERP responses to stimuli that come from different directions. No evidence of auditory hemispatial bias in the SCZ patients was found, supporting the existence of non-lateralized spatial processing deficits in such patients and suggesting compensatory changes in the hemispheric laterality of patients' brains.
Collapse
Affiliation(s)
- Sara Sardari
- Neuroscience Research center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Ali Mohammad Pourrahimi
- Neuroscience Research center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Hossein Talebi
- Audiology department, Rehabilitation faculty, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Shahrzad Mazhari
- Neuroscience Research center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran.
- Department of Psychiatry, Medical School, Kerman University of Medical Sciences, Kerman, Iran.
| |
Collapse
|
23
|
Luck SJ, Hahn B, Leonard CJ, Gold JM. The Hyperfocusing Hypothesis: A New Account of Cognitive Dysfunction in Schizophrenia. Schizophr Bull 2019; 45:991-1000. [PMID: 31317191 PMCID: PMC6737469 DOI: 10.1093/schbul/sbz063] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Impairments in basic cognitive processes such as attention and working memory are commonly observed in people with schizophrenia and are predictive of long-term outcome. In this review, we describe a new theory-the hyperfocusing hypothesis-which provides a unified account of many aspects of impaired cognition in schizophrenia. This hypothesis proposes that schizophrenia involves an abnormally narrow but intense focusing of processing resources. This hyperfocusing impairs the ability of people with schizophrenia to distribute attention among multiple locations, decreases the number of representations that can simultaneously be maintained in working memory, and causes attention to be abnormally captured by irrelevant inputs that share features with active representations. Evidence supporting the hyperfocusing hypothesis comes from a variety of laboratory tasks and from both behavioral and electrophysiological measures of processing. In many of these tasks, people with schizophrenia exhibit supranormal effects of task manipulations, which cannot be explained by a generalized cognitive deficit or by nonspecific factors such as reduced motivation or poor task comprehension. In addition, the degree of hyperfocusing in these tasks is often correlated with the degree of impairment in measures of broad cognitive function, which are known to be related to long-term outcome. Thus, the mechanisms underlying hyperfocusing may be a good target for new treatments targeting cognitive deficits in schizophrenia.
Collapse
Affiliation(s)
- Steven J Luck
- Center for Mind and Brain, University of California, Davis, CA
| | - Britta Hahn
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD
| | - Carly J Leonard
- Department of Psychology, University of Colorado Denver, Denver, CO
| | - James M Gold
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD
| |
Collapse
|
24
|
Abstract
Recent evidence suggests that schizophrenia involves hyperfocusing, an unusually narrow but intense focusing of processing resources. This appears to contradict the classic idea that schizophrenia involves an impairment in the ability to focus on relevant information and filter irrelevant information. Here, we review one set of studies suggesting that attentional filtering is impaired in people with schizophrenia and another set of studies suggesting that attentional filtering is unimpaired or even enhanced in these individuals. Considerable evidence supports both conclusions, and we propose 3 potential ways of reconciling the conflicting evidence. First, impaired attentional filtering may occur primarily during periods of active psychosis, with hyperfocusing being a part of the broad pattern of cognitive impairment that persists independent of the level of positive symptoms. Second, schizophrenia may involve hyperfocusing in the visual modality and impaired attentional filtering in the auditory modality. Third, attention may be directed toward irrelevant inputs as a result of impaired executive control, and hyperfocusing on those inputs may be functionally equivalent to a failure of attentional filtering. Given the widespread clinical observations and first-person reports of impaired attentional filtering in schizophrenia, it will be important for future research to test these possibilities.
Collapse
Affiliation(s)
- Steven J Luck
- Center for Mind & Brain, University of California, Davis, Davis, CA,To whom correspondence should be addressed; tel: 530-297-4424, fax: 530-754-4500, e-mail:
| | - Carly J Leonard
- Department of Psychology, University of Colorado, Denver, CO
| | - Britta Hahn
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD
| | - James M Gold
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD
| |
Collapse
|
25
|
Leonard CJ, Robinson BM, Hahn B, Luck SJ, Gold JM. Altered spatial profile of distraction in people with schizophrenia. JOURNAL OF ABNORMAL PSYCHOLOGY 2019; 126:1077-1086. [PMID: 29154568 DOI: 10.1037/abn0000314] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Attention is critical for effective processing of incoming information and has long been identified as a potential area of dysfunction in people with schizophrenia (PSZ). In the realm of visual processing, both spatial attention and feature-based attention are involved in biasing selection toward task-relevant stimuli and avoiding distraction. Evidence from multiple paradigms has suggested that PSZ may hyperfocus and have a narrower "spotlight" of spatial attention. In contrast, feature-based attention seems largely preserved, with some suggestion of increased processing of stimuli sharing the target-defining feature. In the current study, we examined the spatial profile of feature-based distraction using a task in which participants searched for a particular color target and attempted to ignore distractors that varied in distance from the target location and either matched or mismatched the target color. PSZ differed from healthy controls in terms of interference from peripheral distractors that shared the target-color presented 200 ms before a central target. Specifically, PSZ showed an amplified gradient of spatial attention, with increased distraction to near distractors and less interference to far distractors. Moreover, consistent with hyperfocusing, individual differences in this spatial profile were correlated with positive symptoms, such that those with greater positive symptoms showed less distraction by target-colored distractors near the task-relevant location. (PsycINFO Database Record
Collapse
Affiliation(s)
| | - Benjamin M Robinson
- Maryland Psychiatric Research Center, University of Maryland School of Medicine
| | - Britta Hahn
- Maryland Psychiatric Research Center, University of Maryland School of Medicine
| | - Steven J Luck
- Center for Mind & Brain and Department of Psychology, University of California, Davis
| | - James M Gold
- Maryland Psychiatric Research Center, University of Maryland School of Medicine
| |
Collapse
|
26
|
Curtin A, Sun J, Zhao Q, Onaral B, Wang J, Tong S, Ayaz H. Visuospatial task-related prefrontal activity is correlated with negative symptoms in schizophrenia. Sci Rep 2019; 9:9575. [PMID: 31270354 PMCID: PMC6610077 DOI: 10.1038/s41598-019-45893-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 06/14/2019] [Indexed: 01/15/2023] Open
Abstract
Control of attention is thought to be specifically impaired in schizophrenia due to abnormal function in the prefrontal cortex (PFC). The PFC plays a critical role in the identification of relevant stimuli and the development of appropriate biases for the identified signals, including selection of an appropriate attentional 'zoom'. We examined how demands associated with changes in attentional requirements in a Sustained Attention Task (SAT) may contribute to differences in functional involvement of the PFC and relation to clinical status. A group of 24 individuals with schizophrenia and 16 healthy controls (N = 40) performed the SAT and a visuospatial condition (vSAT) while activity in the bilateral anterior PFC was monitored using functional Near Infrared Spectroscopy (fNIRS). The results confirm that the right frontopolar region plays a role in control of attention for both patients and healthy controls. However, patients with schizophrenia exhibited a general attentional deficit and inefficient right-medial PFC activation. Additionally, we observed a strong regional association between left Middle Frontal Gyrus (MFG) activity during the vSAT task and the PANSS score driven by the negative symptom subscale. The presence of aberrant activation differences within the left-MFG region may describe a dysregulation of attentional networks linked to the clinical expression of negative and general symptoms.
Collapse
Affiliation(s)
- Adrian Curtin
- Drexel University, School of Biomedical Engineering, Science and Health Systems, Philadelphia, PA, USA
- Shanghai Jiao Tong University, School of Biomedical Engineering, Shanghai, China
| | - Junfeng Sun
- Shanghai Jiao Tong University, School of Biomedical Engineering, Shanghai, China
| | - Qiangfeng Zhao
- Shanghai Jiao Tong University, School of Biomedical Engineering, Shanghai, China
| | - Banu Onaral
- Drexel University, School of Biomedical Engineering, Science and Health Systems, Philadelphia, PA, USA
| | - Jijun Wang
- Shanghai Mental Health Center, Shanghai Jiao Tong University, School of Medicine, Shanghai, China.
| | - Shanbao Tong
- Shanghai Jiao Tong University, School of Biomedical Engineering, Shanghai, China.
| | - Hasan Ayaz
- Drexel University, School of Biomedical Engineering, Science and Health Systems, Philadelphia, PA, USA.
- University of Pennsylvania, Department of Family and Community Health, Philadelphia, PA, USA.
- Children's Hospital of Philadelphia, Center for Injury Research and Prevention, Philadelphia, PA, USA.
| |
Collapse
|
27
|
Spironelli C, Romeo Z, Maffei A, Angrilli A. Comparison of automatic visual attention in schizophrenia, bipolar disorder, and major depression: Evidence from P1 event-related component. Psychiatry Clin Neurosci 2019; 73:331-339. [PMID: 30882991 DOI: 10.1111/pcn.12840] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 02/08/2019] [Accepted: 03/10/2019] [Indexed: 01/12/2023]
Abstract
AIM The ability to discern commonalities and differences in the neurobiology of functional psychoses represents a key element to unmasking shared vulnerability across different psychiatric conditions. The present study sought to compare the automatic visual attention mechanisms in three psychiatric disorders considered to distribute along the continuum of psychosis severity: schizophrenia (SCZ), bipolar disorder (BD), and major depressive disorder (MDD). To this end, the visual P1 event-related potential component, a cortical correlate of automatic visual attention, was measured during an ecological task based on visual word pair presentation. METHODS Four samples of participants, 18 SCZ, 20 BD, 28 MDD, and 30 healthy controls, were recruited and submitted to the same procedure and stimuli. The P1 evoked by visual word presentation was recorded through a 38-electrode electroencephalography cap. Words were presented on a computer screen serially as pairs, and participants had to decide whether they rhymed or not. RESULTS P1 was larger at posterior sites in SCZ compared with BD, healthy control, and MDD participants. BD patients showed the lowest P1 compared with all other groups. Positive Pearson's correlations were found in SCZ patients between P1 amplitude on left posterior sites and both hallucination severity and worse task performance. CONCLUSION The three investigated psychiatric samples showed different automatic visual attention patterns: SCZ patients exhibited the greatest cognitive impairment correlated with the amplitude of P1, MDD patients revealed a normal component, and BD showed a compensated euthymic response different from results of past literature in untreated patients.
Collapse
Affiliation(s)
- Chiara Spironelli
- Department of General Psychology, University of Padua, Padua, Italy.,Padua Neuroscience Center, Padua, Italy
| | | | - Antonio Maffei
- Department of General Psychology, University of Padua, Padua, Italy
| | - Alessandro Angrilli
- Department of General Psychology, University of Padua, Padua, Italy.,Padua Neuroscience Center, Padua, Italy.,IN-CNR Institute of Neuroscience CNR, Padua, Italy
| |
Collapse
|
28
|
Hahn B, Reneski CH, Pocivavsek A, Schwarcz R. Prenatal kynurenine treatment in rats causes schizophrenia-like broad monitoring deficits in adulthood. Psychopharmacology (Berl) 2018; 235:651-661. [PMID: 29128872 PMCID: PMC5823752 DOI: 10.1007/s00213-017-4780-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Accepted: 11/01/2017] [Indexed: 12/12/2022]
Abstract
RATIONALE Elevated brain kynurenic acid (KYNA) levels are implicated in the pathology and neurodevelopmental pathogenesis of schizophrenia. In rats, embryonic treatment with kynurenine (EKyn) causes elevated brain KYNA levels in adulthood and cognitive deficits reminiscent of schizophrenia. OBJECTIVES Growing evidence suggests that people with schizophrenia have a narrowed attentional focus, and we aimed at establishing whether these abnormalities may be related to KYNA dysregulation. METHODS To test whether EKyn rats display broad monitoring deficits, kynurenine was added to the chow of pregnant Wistar dams on embryonic days 15-22. As adults, 20 EKyn and 20 control rats were trained to stable performance on the five-choice serial reaction time task, requiring the localization of 1-s light stimuli presented randomly across five apertures horizontally arranged along a curved wall, equating the locomotor demands of reaching each hole. RESULTS EKyn rats displayed elevated omission errors and reduced anticipatory responses relative to control rats, indicative of a lower response rate, and showed reduced locomotor activity. The ability to spread attention broadly was measured by parsing performance by stimulus location. Both groups displayed poorer stimulus detection with greater target location eccentricity, but this effect was significantly more pronounced in the EKyn group. Specifically, the groups differed in the spatial distribution of correct but not incorrect responses. This pattern cannot be explained by differences in response rate and is indicative of a narrowed attentional focus. CONCLUSIONS The findings suggest a potential etiology of broad monitoring deficits in schizophrenia, which may constitute a core cognitive deficit.
Collapse
Affiliation(s)
- Britta Hahn
- Maryland Psychiatric Research Center, University of Maryland School of Medicine, P.O. Box 21247, Baltimore, MD, 21228, USA.
| | | | | | | |
Collapse
|