Cognitive Neuroscience Approaches to the Psychopathology of Psychotic Disorders

A special issue of Brain Sciences (ISSN 2076-3425). This special issue belongs to the section "Psychiatric Diseases".

Deadline for manuscript submissions: closed (31 March 2023) | Viewed by 35483

Special Issue Editor


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Guest Editor
Department of Psychiatry, Queen Mary Hospital, The University of Hong Kong, Pokfulam, Hong Kong
Interests: cognitive neuroscience of schizophrenia; cognitive and experiential aspects of psychopathology; suicide studies; digital psychiatry; psychiatric epidemiology

Special Issue Information

Dear Colleagues,

Brain abnormalities have been increasingly recognized in schizophrenia. They have been investigated through cognitive neuropsychological and neuroimaging approaches. Neurocognitive dysfunctions in psychotic disorders such as schizophrenia are particularly important as they not only shed light into the brain systems and processes involved in the disorder, but also in our understanding of some of the most disabling functioning impairments in the disorder. In addition to resource-intensive investigations, more portable and simpler neurocognitive markers may enable information to be collected in larger cohorts of patients under more real-life contexts. This issue invites contributions concerning the use of a range of neurocognitive approaches to investigate the psychopathology of psychotic disorders.

Prof. Dr. Eric Chen
Guest Editor

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Keywords

  • markers
  • endophenotypes
  • neuro-cognitive
  • brain
  • psychosis
  • schizophrenia
  • neuropsychology
  • cognition

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Published Papers (15 papers)

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Editorial

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5 pages, 201 KiB  
Editorial
Unique Challenges in Biomarkers for Psychotic Disorders
by Eric Y. H. Chen and Stephanie M. Y. Wong
Brain Sci. 2024, 14(1), 106; https://doi.org/10.3390/brainsci14010106 - 22 Jan 2024
Cited by 1 | Viewed by 1357
Abstract
Biomarkers are observations that provide information about the risk of certain conditions (predictive) or their underlying mechanisms (explanatory) [...] Full article

Research

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15 pages, 308 KiB  
Article
Analysis of Educational Attainment in a Mexican Psychiatric Patient Population with Bipolar or Psychotic Disorders
by Hugo Cano-Ramirez, Lina Diaz-Castro and Kurt Leroy Hoffman
Brain Sci. 2023, 13(6), 881; https://doi.org/10.3390/brainsci13060881 - 30 May 2023
Viewed by 1350
Abstract
Schizophrenia has been associated with premorbid poor educational performance and low educational attainment (EA). However, some studies have found positive associations between psychotic disorders and excellent scholastic performance. In the present study, we examined the association between EA and several clinical and nonclinical [...] Read more.
Schizophrenia has been associated with premorbid poor educational performance and low educational attainment (EA). However, some studies have found positive associations between psychotic disorders and excellent scholastic performance. In the present study, we examined the association between EA and several clinical and nonclinical characteristics in psychiatric patients diagnosed with psychotic or bipolar disorders. Data were obtained from the files of 1132 patients who entered a major Mexico City psychiatric hospital during the years 2009–2010 for the treatment of psychotic symptoms and who were subsequently diagnosed with schizophrenia, bipolar, schizoaffective, or another psychotic disorder. Chi-squared tests, t-tests, and Cox regression analysis were applied to explore associations between EA and factors including gender, familial history of mental illness, premorbid personality characteristics, age of symptom onset, diagnosis, civil status, and current employment. Family history of mental illness decreased the hazard of having lower EA (B = −0.137, p = 0.025, ExpB = 0.872, 95% CI = 0.774–0.983), while a schizophrenia diagnosis independently increased it (B = 0.201, p = 0.004, ExpB = 1.223, 95% CI = 1.068–1.401). In male patients (but not in females), family history of mental illness was significantly associated with higher EA, while in female patients, premorbid schizoid-like personality characteristics were associated with lower EA. For both genders, lower EA was associated with having more children and being employed in manual labor, while higher EA was associated with professional employment. Conclusions: Compared with bipolar disorder, a schizophrenia diagnosis is associated with lower EA; however, familial history of mental illness and premorbid schizoid-like characteristics independently favor higher and lower EA in males and females, respectively. Since lower EA is generally associated with a lower economic status, special preventative attention should be given to students at high risk for schizophrenia, particularly those displaying a schizoid-like personality. Full article
11 pages, 5717 KiB  
Article
Prolonged Intrinsic Neural Timescales Dissociate from Phase Coherence in Schizophrenia
by Stephan Lechner and Georg Northoff
Brain Sci. 2023, 13(4), 695; https://doi.org/10.3390/brainsci13040695 - 21 Apr 2023
Cited by 10 | Viewed by 1969
Abstract
Input processing in the brain is mediated by phase synchronization and intrinsic neural timescales, both of which have been implicated in schizophrenia. Their relationship remains unclear, though. Recruiting a schizophrenia EEG sample from the B-SNIP consortium dataset (n = 134, 70 schizophrenia [...] Read more.
Input processing in the brain is mediated by phase synchronization and intrinsic neural timescales, both of which have been implicated in schizophrenia. Their relationship remains unclear, though. Recruiting a schizophrenia EEG sample from the B-SNIP consortium dataset (n = 134, 70 schizophrenia patients, 64 controls), we investigate phase synchronization, as measured by intertrial phase coherence (ITPC), and intrinsic neural timescales, as measured by the autocorrelation window (ACW) during both the rest and oddball-task states. The main goal of our paper was to investigate whether reported shifts from shorter to longer timescales are related to decreased ITPC. Our findings show (i) decreases in both theta and alpha ITPC in response to both standard and deviant tones; and (iii) a negative correlation of ITPC and ACW in healthy subjects while such correlation is no longer present in SCZ participants. Together, we demonstrate evidence of abnormally long intrinsic neural timescales (ACW) in resting-state EEG of schizophrenia as well as their dissociation from phase synchronization (ITPC). Our data suggest that, during input processing, the resting state’s abnormally long intrinsic neural timescales tilt the balance of temporal segregation and integration towards the latter. That results in temporal imprecision with decreased phase synchronization in response to inputs. Our findings provide further evidence for a basic temporal disturbance in schizophrenia on the different timescales (longer ACW and shorter ITPC), which, in the future, might be able to explain common symptoms related to the temporal experience in schizophrenia, for example temporal fragmentation. Full article
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17 pages, 2368 KiB  
Article
Using Automated Speech Processing for Repeated Measurements in a Clinical Setting of the Behavioral Variability in the Stroop Task
by Terje B. Holmlund, Alex S. Cohen, Jian Cheng, Peter W. Foltz, Jared Bernstein, Elizabeth Rosenfeld, Bruno Laeng and Brita Elvevåg
Brain Sci. 2023, 13(3), 442; https://doi.org/10.3390/brainsci13030442 - 4 Mar 2023
Cited by 1 | Viewed by 2070
Abstract
The Stroop interference task is indispensable to current neuropsychological practice. Despite this, it is limited in its potential for repeated administration, its sensitivity and its demands on professionals and their clients. We evaluated a digital Stroop deployed using a smart device. Spoken responses [...] Read more.
The Stroop interference task is indispensable to current neuropsychological practice. Despite this, it is limited in its potential for repeated administration, its sensitivity and its demands on professionals and their clients. We evaluated a digital Stroop deployed using a smart device. Spoken responses were timed using automated speech recognition. Participants included adult nonpatients (N = 113; k = 5 sessions over 5 days) and patients with psychiatric diagnoses (N = 85; k = 3–4 sessions per week over 4 weeks). Traditional interference (difference in response time between color incongruent words vs. color neutral words; M = 0.121 s) and facilitation (neutral vs. color congruent words; M = 0.085 s) effects were robust and temporally stable over testing sessions (ICCs 0.50–0.86). The performance showed little relation to clinical symptoms for a two-week window for either nonpatients or patients but was related to self-reported concentration at the time of testing for both groups. Performance was also related to treatment outcomes in patients. The duration of response word utterances was longer in patients than in nonpatients. Measures of intra-individual variability showed promise for understanding clinical state and treatment outcome but were less temporally stable than measures based solely on average response time latency. This framework of remote assessment using speech processing technology enables the fine-grained longitudinal charting of cognition and verbal behavior. However, at present, there is a problematic lower limit to the absolute size of the effects that can be examined when using voice in such a brief ‘out-of-the-laboratory condition’ given the temporal resolution of the speech-to-text detection system (in this case, 10 ms). This resolution will limit the parsing of meaningful effect sizes. Full article
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12 pages, 298 KiB  
Article
What Drives Animal Fluency Performance in Cantonese-Speaking Chinese Patients with Adult-Onset Psychosis?
by Christy Lai-Ming Hui, Sally Hiu-Wah See, Tsz-Ching Chiu, Andrea Stephanie Pintos, Johanna M. Kroyer, Yi-Nam Suen, Edwin Ho-Ming Lee, Sherry Kit-Wa Chan, Wing-Chung Chang, Brita Elvevåg and Eric Yu-Hai Chen
Brain Sci. 2023, 13(3), 372; https://doi.org/10.3390/brainsci13030372 - 21 Feb 2023
Viewed by 1882
Abstract
Among the numerous studies investigating semantic factors associated with functioning in psychotic patients, most have been conducted on western populations. By contrast, the current cross-sectional study involved native Cantonese-speaking Chinese participants. Using the category fluency task, we compared performance between patients and healthy [...] Read more.
Among the numerous studies investigating semantic factors associated with functioning in psychotic patients, most have been conducted on western populations. By contrast, the current cross-sectional study involved native Cantonese-speaking Chinese participants. Using the category fluency task, we compared performance between patients and healthy participants and examined clinical and sociodemographic correlates. First-episode psychosis patients (n = 356) and gender- and age-matched healthy participants (n = 35) were asked to generate as many ‘animals’ as they could in a minute. As expected, patients generated fewer correct responses (an average of 15.5 vs. 22.9 words), generated fewer clusters (an average of 3.7 vs. 5.4 thematically grouped nouns), switched less between clusters (on average 8.0 vs. 11.9 switches) and, interestingly, produced a larger percentage of Chinese zodiac animals than healthy participants (an average of 37.7 vs. 24.2). However, these significant group differences in the clusters and switches disappeared when the overall word production was controlled for. Within patients, education was the strongest predictor of category fluency performance (namely the number of correct responses, clusters, and switches). The findings suggest that an overall slowness in patients may account for the group differences in category fluency performance rather than any specific abnormality per se. Full article
9 pages, 487 KiB  
Article
Impact of Cognitive Impairments on Health-Related Quality of Life in Schizophrenia
by Gurpreet Rekhi, Young Ern Saw, Keane Lim, Richard S. E. Keefe and Jimmy Lee
Brain Sci. 2023, 13(2), 215; https://doi.org/10.3390/brainsci13020215 - 28 Jan 2023
Cited by 7 | Viewed by 2342
Abstract
The impact of cognitive impairments on the health-related quality of life (HRQoL) in individuals with schizophrenia is unclear. The aim of this study was to examine the association between cognitive impairments and HRQoL in individuals with schizophrenia. A total of 609 individuals with [...] Read more.
The impact of cognitive impairments on the health-related quality of life (HRQoL) in individuals with schizophrenia is unclear. The aim of this study was to examine the association between cognitive impairments and HRQoL in individuals with schizophrenia. A total of 609 individuals with schizophrenia were assessed on the Positive and Negative Syndrome Scale (PANSS) and a neurocognitive battery which comprised of the Wechsler Abbreviated Scale of Intelligence matrix reasoning, the Benton Judgment of Line Orientation Test, Continuous Performance Tests-Identical Pairs, and the Brief Assessment of Cognition in Schizophrenia. A cognitive factor g was derived from the neurocognitive battery. EuroQol five-dimensional (EQ-5D-5L) utility scores were derived from PANSS scores via a previously validated algorithm and used as a measure of HRQoL. Hierarchical multiple regression was conducted to examine the association between cognitive factor g and the EQ-5D-5L. Cognitive factor g (β = 0.189, t = 4.956, p < 0.001) was found to be significantly associated with EQ-5D-5L scores. Age (β = −0.258, t = −6.776, p < 0.001), sex (β = 0.081, t = 2.117, p = 0.035), and being employed (β = 0.091, t = 2.317, p = 0.021) were also significant predictors of EQ-5D-5L. Our results add to the extant literature on the burden cognitive impairments exact in individuals with schizophrenia. More research is needed to develop effective interventions for cognitive impairments in schizophrenia. Full article
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11 pages, 1764 KiB  
Article
The Photic Stimulation Has an Impact on the Reproduction of 10 s Intervals Only in Healthy Controls but Not in Patients with Schizophrenia: The EEG Study
by Galina V. Portnova and Aleksandra V. Maslennikova
Brain Sci. 2023, 13(1), 112; https://doi.org/10.3390/brainsci13010112 - 7 Jan 2023
Cited by 2 | Viewed by 1814
Abstract
Schizophrenia is a mental disorder characterized by both abnormal time perception and atypical relationships with external factors. Here we compare the influence of external photic stimulation on time production between healthy subjects (n = 24) and patients with schizophrenia (n = [...] Read more.
Schizophrenia is a mental disorder characterized by both abnormal time perception and atypical relationships with external factors. Here we compare the influence of external photic stimulation on time production between healthy subjects (n = 24) and patients with schizophrenia (n = 22). To delve into neuropsychological mechanisms of such a relationship, the EEG was recorded during variable conditions: during production of 10 s intervals; during photic stimulation of 4, 9, 16, and 25 Hz; and during combinations of these conditions. We found that the higher frequency of photic stimulation influenced the production of time intervals in healthy volunteers, which became significantly longer and were accompanied by corresponding EEG changes. The impact of photic stimulation was absent in patients with schizophrenia. In addition, the time production was characterized by less accuracy and the absence of EEG dynamics typical for healthy controls that included an increase in alpha2 power and envelope frequency. Our findings indicated that the time perception was not adjusted by external factors in patients with schizophrenia and might have involved cognitive and mental processes different from those of healthy volunteers. Full article
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10 pages, 270 KiB  
Article
Characteristics of Families with Members Going Out for Work and Associated Factors among Persons with Schizophrenia in Rural China
by Jia Cai, Yu-Jun Liu, Xian-Dong Meng, Yi Huang, Bo Liu and Mao-Sheng Ran
Brain Sci. 2022, 12(11), 1518; https://doi.org/10.3390/brainsci12111518 - 9 Nov 2022
Viewed by 1325
Abstract
Background: The characteristics associated with having family members going out for work among persons with schizophrenia in rural China are unknown. This study aimed to explore the characteristics of families with members going out for work and the risk factors among persons with [...] Read more.
Background: The characteristics associated with having family members going out for work among persons with schizophrenia in rural China are unknown. This study aimed to explore the characteristics of families with members going out for work and the risk factors among persons with schizophrenia in a rural area of China. Methods: This study employed a cross-sectional dataset from a mental health survey, using the International Classification of Disease, Tenth Revision (ICD-10), conducted among 152,776 people aged 15 years and older in Xinjin District, Chengdu, China, in 2015. Results: A total of 598 persons with schizophrenia were included in this study, and 20.4% (n = 122) of them had at least one family member who went out for work. Compared with those without family going out for work, participants with family going out for work had significantly larger numbers of family members, higher monthly incomes and lower percentages of social low-income insurance. Participants with family going out for work were more likely to be females, married and with higher levels of subjective and instrumental support. The statuses of families with members going out for work were significantly associated with larger numbers of family members and higher levels of instrumental support. Conclusions: Our findings indicate specific characteristics of families with members going out for work and factors associated with having family going out for work among persons with schizophrenia (number of family members and instrumental support). Culture-specific mental health policies and community-based services should be developed for persons with schizophrenia who have family going out for work in rural China. Full article
18 pages, 2636 KiB  
Article
Frequency-Specific Analysis of the Dynamic Reconfiguration of the Brain in Patients with Schizophrenia
by Yanli Yang, Yang Zhang, Jie Xiang, Bin Wang, Dandan Li, Xueting Cheng, Tao Liu and Xiaohong Cui
Brain Sci. 2022, 12(6), 727; https://doi.org/10.3390/brainsci12060727 - 1 Jun 2022
Cited by 2 | Viewed by 2178
Abstract
The analysis of resting-state fMRI signals usually focuses on the low-frequency range/band (0.01–0.1 Hz), which does not cover all aspects of brain activity. Studies have shown that distinct frequency bands can capture unique fluctuations in brain activity, with high-frequency signals (>0.1 Hz) providing [...] Read more.
The analysis of resting-state fMRI signals usually focuses on the low-frequency range/band (0.01–0.1 Hz), which does not cover all aspects of brain activity. Studies have shown that distinct frequency bands can capture unique fluctuations in brain activity, with high-frequency signals (>0.1 Hz) providing valuable information for the diagnosis of schizophrenia. We hypothesized that it is meaningful to study the dynamic reconfiguration of schizophrenia through different frequencies. Therefore, this study used resting-state functional magnetic resonance (RS-fMRI) data from 42 schizophrenia and 40 normal controls to investigate dynamic network reconfiguration in multiple frequency bands (0.01–0.25 Hz, 0.01–0.027 Hz, 0.027–0.073 Hz, 0.073–0.198 Hz, 0.198–0.25 Hz). Based on the time-varying dynamic network constructed for each frequency band, we compared the dynamic reconfiguration of schizophrenia and normal controls by calculating the recruitment and integration. The experimental results showed that the differences between schizophrenia and normal controls are observed in the full frequency, which is more significant in slow3. In addition, as visual network, attention network, and default mode network differ a lot from each other, they can show a high degree of connectivity, which indicates that the functional network of schizophrenia is affected by the abnormal brain state in these areas. These shreds of evidence provide a new perspective and promote the current understanding of the characteristics of dynamic brain networks in schizophrenia. Full article
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12 pages, 920 KiB  
Article
The Impact of Electroconvulsive Therapy on Negative Symptoms in Schizophrenia and Their Association with Clinical Outcomes
by Xiaowei Tan, Donel Martin, Jimmy Lee and Phern Chern Tor
Brain Sci. 2022, 12(5), 545; https://doi.org/10.3390/brainsci12050545 - 25 Apr 2022
Cited by 2 | Viewed by 3244
Abstract
Objective: The treatment efficacy of electroconvulsive therapy (ECT) for negative symptoms amongst patients with schizophrenia remains unclear. In this study, we aim to examine the effects of ECT on negative symptoms in schizophrenia and their association with other clinical outcomes, including cognition and [...] Read more.
Objective: The treatment efficacy of electroconvulsive therapy (ECT) for negative symptoms amongst patients with schizophrenia remains unclear. In this study, we aim to examine the effects of ECT on negative symptoms in schizophrenia and their association with other clinical outcomes, including cognition and function. Methods: This is a retrospective data analysis of patients with schizophrenia/schizoaffective disorder treated with ECT at the Institute of Mental Health (IMH), Singapore, between January 2016 and December 2019. Clinical outcomes were assessed by the Brief Psychiatric Rating Scale (BPRS), the Montreal Cognitive Assessment (MoCA), and Global Assessment of Function (GAF). Changes in scores were compared with repeated measures analysis of variance. Sequential structural modelling was utilized to examine the pathway relationships between changes in negative symptoms, global functioning, and cognition functioning after ECT. Results: A total of 340 patients were analysed. Hence, 196 (57.6%), 53 (15.5%), and 91 (26.7%) showed improvements, no change, and deterioration in negative symptoms, respectively. ECT-induced improvement of negative symptoms was significantly associated with improvement of global functioning (direct effect correlation coefficient (r): −0.496; se: 0.152; p = 0.001) and cognition function (indirect effect r: −0.077; se: 0.037; p = 0.035). Moreover, having capacity to consent, more severe baseline negative symptoms, lithium prescription, and an indirect effect of voluntary admission status via consent capacity predicted ECT associated negative symptoms improvement. Conclusion: ECT is generally associated with improvements of negative symptoms in people with schizophrenia, which correlate with improvements of overall function. Possible novel clinical predictors of negative symptom improvement have been identified and will require further research and validation. Full article
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Review

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17 pages, 957 KiB  
Review
Rumination as a Transdiagnostic Phenomenon in the 21st Century: The Flow Model of Rumination
by Stephanie M. Y. Wong, Eric Y. H. Chen, Michelle C. Y. Lee, Y. N. Suen and Christy L. M. Hui
Brain Sci. 2023, 13(7), 1041; https://doi.org/10.3390/brainsci13071041 - 8 Jul 2023
Cited by 8 | Viewed by 4282
Abstract
Rumination and its related mental phenomena share associated impairments in cognition, such as executive functions and attentional processes across different clinical conditions (e.g., in psychotic disorders). In recent decades, however, the notion of rumination has been increasingly narrowed to the “self-focused” type in [...] Read more.
Rumination and its related mental phenomena share associated impairments in cognition, such as executive functions and attentional processes across different clinical conditions (e.g., in psychotic disorders). In recent decades, however, the notion of rumination has been increasingly narrowed to the “self-focused” type in depressive disorders. A closer review of the literature shows that rumination may be construed as a broader process characterized by repetitive thoughts about certain mental contents that interfere with one’s daily activities, not only limited to those related to “self”. A further examination of the construct of rumination beyond the narrowly focused depressive rumination would help expand intervention opportunities for mental disorders in today’s context. We first review the development of the clinical construct of rumination with regard to its historical roots and its roles in psychopathology. This builds the foundation for the introduction of the “Flow Model of Rumination (FMR)”, which conceptualizes rumination as a disruption of a smooth flow of mental contents in conscious experience that depends on the coordinated interactions between intention, memory, affect, and external events. The conceptual review concludes with a discussion of the impact of rapid technological advances (such as smartphones) on rumination. Particularly in contemporary societies today, a broader consideration of rumination not only from a cognition viewpoint, but also incorporating a human–device interaction perspective, is necessitated. The implications of the FMR in contemporary mental health practice are discussed. Full article
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Other

20 pages, 751 KiB  
Hypothesis
Spurious Autobiographical Memory of Psychosis: A Mechanistic Hypothesis for the Resolution, Persistence, and Recurrence of Positive Symptoms in Psychotic Disorders
by Eric Y. H. Chen, Stephanie M. Y. Wong, Eric Y. H. Tang, Lauren K. S. Lei, Yi-nam Suen and Christy L. M. Hui
Brain Sci. 2023, 13(7), 1069; https://doi.org/10.3390/brainsci13071069 - 13 Jul 2023
Cited by 1 | Viewed by 2556
Abstract
Psychotic disorders are complex disorders with multiple etiologies. While increased dopamine synthesis capacity has been proposed to underlie psychotic episodes, dopamine-independent processes are also involved (less responsive to dopamine receptor-blocking medications). The underlying mechanism(s) of the reduction in antipsychotic responsiveness over time, especially [...] Read more.
Psychotic disorders are complex disorders with multiple etiologies. While increased dopamine synthesis capacity has been proposed to underlie psychotic episodes, dopamine-independent processes are also involved (less responsive to dopamine receptor-blocking medications). The underlying mechanism(s) of the reduction in antipsychotic responsiveness over time, especially after repeated relapses, remain unclear. Despite the consistent evidence of dopamine overactivity and hippocampal volume loss in schizophrenia, few accounts have been provided based on the interactive effect of dopamine on hippocampal synapse plasticity mediating autobiographical memory processes. The present hypothesis builds upon previous works showing the potential effects of dopamine overactivity on hippocampal-mediated neuroplasticity underlying autobiographical memory, alongside known patterns of autobiographical memory dysfunction in psychosis. We propose that spurious autobiographical memory of psychosis (SAMP) produced during active psychosis may be a key mechanism mediating relapses and treatment non-responsiveness. In a hyperdopaminergic state, SAMP is expected to be generated at an increased rate during active psychosis. Similar to other memories, it will undergo assimilation, accommodation, and extinction processes. However, if SAMP fails to integrate with existing memory, a discontinuity in autobiographical memory may result. Inadequate exposure to normalizing experiences and hyposalience due to overmedication or negative symptoms may also impede the resolution of SAMP. Residual SAMP is hypothesized to increase the propensity for relapse and treatment non-responsiveness. Based on recent findings on the role of dopamine in facilitating hippocampal synapse plasticity and autobiographical memory formation, the SAMP hypothesis is consistent with clinical observations of DUP effects, including the repetition of contents in psychotic relapses as well as the emergence of treatment non-responsiveness after repeated relapses. Clinical implications of the hypothesis highlight the importance of minimizing active psychosis, integrating psychosis memory, avoiding over-medication, and fostering normalizing experiences. Full article
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21 pages, 853 KiB  
Systematic Review
Towards a Neurophenomenological Understanding of Self-Disorder in Schizophrenia Spectrum Disorders: A Systematic Review and Synthesis of Anatomical, Physiological, and Neurocognitive Findings
by James C. Martin, Scott R. Clark and K. Oliver Schubert
Brain Sci. 2023, 13(6), 845; https://doi.org/10.3390/brainsci13060845 - 23 May 2023
Cited by 5 | Viewed by 2324
Abstract
The concept of anomalous self-experience, also termed Self-Disorder, has attracted both clinical and research interest, as empirical studies suggest such experiences specifically aggregate in and are a core feature of schizophrenia spectrum disorders. A comprehensive neurophenomenological understanding of Self-Disorder may improve diagnostic and [...] Read more.
The concept of anomalous self-experience, also termed Self-Disorder, has attracted both clinical and research interest, as empirical studies suggest such experiences specifically aggregate in and are a core feature of schizophrenia spectrum disorders. A comprehensive neurophenomenological understanding of Self-Disorder may improve diagnostic and therapeutic practice. This systematic review aims to evaluate anatomical, physiological, and neurocognitive correlates of Self-Disorder (SD), considered a core feature of Schizophrenia Spectrum Disorders (SSDs), towards developing a neurophenomenological understanding. A search of the PubMed database retrieved 285 articles, which were evaluated for inclusion using PRISMA guidelines. Non-experimental studies, studies with no validated measure of Self-Disorder, or those with no physiological variable were excluded. In total, 21 articles were included in the review. Findings may be interpreted in the context of triple-network theory and support a core dysfunction of signal integration within two anatomical components of the Salience Network (SN), the anterior insula and dorsal anterior cingulate cortex, which may mediate connectivity across both the Default Mode Network (DMN) and Fronto-Parietal Network (FPN). We propose a theoretical Triple-Network Model of Self-Disorder characterized by increased connectivity between the Salience Network (SN) and the DMN, increased connectivity between the SN and FPN, decreased connectivity between the DMN and FPN, and increased connectivity within both the DMN and FPN. We go on to describe translational opportunities for clinical practice and provide suggestions for future research. Full article
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26 pages, 694 KiB  
Systematic Review
Application of Immersive Virtual Reality for Assessment and Intervention in Psychosis: A Systematic Review
by Karen Chui-Shan Chan, Christy Lai-Ming Hui, Yi-Nam Suen, Edwin Ho-Ming Lee, Wing-Chung Chang, Sherry Kit-Wa Chan and Eric Yu-Hai Chen
Brain Sci. 2023, 13(3), 471; https://doi.org/10.3390/brainsci13030471 - 10 Mar 2023
Cited by 3 | Viewed by 3176
Abstract
Virtual reality (VR) has emerged as a safe and non-invasive technology for the assessment of psychotic symptoms, social and cognitive impairments, and psychosocial intervention in improving outcomes in psychosis. This study systematically reviewed the current state of evidence in applying semi- and fully [...] Read more.
Virtual reality (VR) has emerged as a safe and non-invasive technology for the assessment of psychotic symptoms, social and cognitive impairments, and psychosocial intervention in improving outcomes in psychosis. This study systematically reviewed the current state of evidence in applying semi- and fully immersive VR for assessing and treating patients with psychosis. A systematic review was conducted adhering to the PRISMA statement and was conducted in Embase, PsycINFO, and PubMed databases for articles published between January 2013 and April 2022, which identified 28 eligible studies, including 12 for assessment and 16 for intervention. In the assessment studies, not all VR tasks could distinguish the differences between patients and healthy controls regarding their physiological responses, paranoid ideation, and certain aspects of cognitive functioning such as memory bias on the object tasks. Comparatively, VR-based interventions are more promising, especially for improving cognitive impairments, social skills, agoraphobic avoidance, negative and positive affective states, auditory verbal hallucination, paranoid ideation and persecutory delusions, and other psychiatric symptoms in patients. We conclude that more rigorous studies are needed to confirm treatment effectiveness and to understand the underlying mechanism of VR-based intervention for psychotic disorders. Future studies should also improve the reliability and validity of VR-based assessments for psychotic disorders. Full article
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15 pages, 536 KiB  
Perspective
Temporal Stability of the Dynamic Resting-State Functional Brain Network: Current Measures, Clinical Research Progress, and Future Perspectives
by Yicheng Long, Xiawei Liu and Zhening Liu
Brain Sci. 2023, 13(3), 429; https://doi.org/10.3390/brainsci13030429 - 1 Mar 2023
Cited by 7 | Viewed by 2278
Abstract
Based on functional magnetic resonance imaging and multilayer dynamic network model, the brain network’s quantified temporal stability has shown potential in predicting altered brain functions. This manuscript aims to summarize current knowledge, clinical research progress, and future perspectives on brain network’s temporal stability. [...] Read more.
Based on functional magnetic resonance imaging and multilayer dynamic network model, the brain network’s quantified temporal stability has shown potential in predicting altered brain functions. This manuscript aims to summarize current knowledge, clinical research progress, and future perspectives on brain network’s temporal stability. There are a variety of widely used measures of temporal stability such as the variance/standard deviation of dynamic functional connectivity strengths, the temporal variability, the flexibility (switching rate), and the temporal clustering coefficient, while there is no consensus to date which measure is the best. The temporal stability of brain networks may be associated with several factors such as sex, age, cognitive functions, head motion, circadian rhythm, and data preprocessing/analyzing strategies, which should be considered in clinical studies. Multiple common psychiatric disorders such as schizophrenia, major depressive disorder, and bipolar disorder have been found to be related to altered temporal stability, especially during the resting state; generally, both excessively decreased and increased temporal stabilities were thought to reflect disorder-related brain dysfunctions. However, the measures of temporal stability are still far from applications in clinical diagnoses for neuropsychiatric disorders partly because of the divergent results. Further studies with larger samples and in transdiagnostic (including schizoaffective disorder) subjects are warranted. Full article
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