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Lasagna CA, Tso IF, Blain SD, Pleskac TJ. Cognitive Mechanisms of Aberrant Self-Referential Social Perception in Psychosis and Bipolar Disorder: Insights from Computational Modeling. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.03.30.24304780. [PMID: 39072038 PMCID: PMC11275667 DOI: 10.1101/2024.03.30.24304780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Background and Hypothesis Individuals with schizophrenia (SZ) and bipolar disorder (BD) show disruptions in self-referential gaze perception-a social perceptual process related to symptoms and functioning. However, our current mechanistic understanding of these dysfunctions and relationships is imprecise. Study Design The present study used mathematical modeling to uncover cognitive processes driving gaze perception abnormalities in SZ and BD, and how they relate to cognition, symptoms, and social functioning. We modeled the behavior of 28 SZ, 38 BD, and 34 controls (HC) in a self-referential gaze perception task using drift-diffusion models (DDM) parameterized to index key cognitive components: drift rate (evidence accumulation efficiency), drift bias (perceptual bias), start point (expectation bias), threshold separation (response caution), and non- decision time (encoding/motor processes). Study Results Results revealed that aberrant gaze perception in SZ and BD was driven by less efficient evidence accumulation, perceptual biases predisposing self-referential responses, and greater caution (SZ only). Across SZ and HC, poorer social functioning was related to greater expectation biases. Within SZ, perceptual and expectancy biases were associated with hallucination and delusion severity, respectively. Conclusions These findings indicate that diminished evidence accumulation and perceptual biases may underlie altered gaze perception in patients and that SZ may engage in compensatory cautiousness, sacrificing response speed to preserve accuracy. Moreover, biases at the belief and perceptual levels may relate to symptoms and functioning. Computational modeling can, therefore, be used to achieve a more nuanced, cognitive process-level understanding of the mechanisms of social cognitive difficulties, including gaze perception, in individuals with SZ and BD.
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Fattal J, Giljen M, Vargas T, Damme KSF, Calkins ME, Pinkham AE, Mittal VA. A Developmental Perspective on Early and Current Motor Abnormalities and Psychotic-Like Symptoms. Schizophr Bull 2024:sbae062. [PMID: 38728386 DOI: 10.1093/schbul/sbae062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/12/2024]
Abstract
BACKGROUND AND HYPOTHESIS Psychotic-like experiences (PLEs) are prevalent in the general population and, because they represent a lower end of the psychosis vulnerability spectrum, may be useful in informing mechanistic understanding. Although it is well-understood that motor signs characterize formal psychotic disorders, the developmental trajectory of these features and their relationships with PLEs are less well-understood. STUDY DESIGN Data from 7559 adolescents and young adults (age 11-21) in the Philadelphia Neurodevelopmental Cohort were used to investigate whether early-life milestone-attainment delays relate to current adolescent sensorimotor functioning and positive and negative PLEs. Current sensorimotor functioning was assessed using the Computerized Finger Tapping task (assessing motor slowing) and Mouse Practice task (assessing sensorimotor planning). STUDY RESULTS Early developmental abnormalities were related to current adolescent-aged motor slowing (t(7415.3) = -7.74, corrected-P < .001) and impaired sensorimotor planning (t(7502.5) = 5.57, corrected-P < .001). There was a significant interaction between developmental delays and current sensorimotor functioning on positive and negative PLEs (t = 1.67-4.51), such that individuals with early developmental delays had a stronger positive relationship between sensorimotor dysfunction and PLEs. Importantly, interaction models were significantly better at explaining current PLEs than those treating early and current sensorimotor dysfunction independently (χ2 = 4.89-20.34). CONCLUSIONS These findings suggest a relationship between early developmental delays and current sensorimotor functioning in psychosis proneness and inform an understanding of heterotypic continuity as well as a neurodevelopmental perspective of motor circuits. Furthermore, results indicate that motor signs are a clear factor in the psychosis continuum, suggesting that they may represent a core feature of psychosis vulnerability.
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Affiliation(s)
- Jessica Fattal
- Department of Psychology, Northwestern University, Evanston, IL, USA
| | - Maksim Giljen
- Department of Psychological Science, University of California, Irvine, Irvine, CA, USA
| | - Teresa Vargas
- Department of Psychology, Harvard University, Cambridge, MA, USA
| | | | - Monica E Calkins
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Amy E Pinkham
- Department of Psychology, University of Texas at Dallas, Richardson, TX, USA
| | - Vijay A Mittal
- Department of Psychology, Northwestern University, Evanston, IL, USA
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Gangl N, Conring F, Federspiel A, Wiest R, Walther S, Stegmayer K. Resting-state perfusion in motor and fronto-limbic areas is linked to diminished expression of emotion and speech in schizophrenia. SCHIZOPHRENIA (HEIDELBERG, GERMANY) 2023; 9:51. [PMID: 37573445 PMCID: PMC10423240 DOI: 10.1038/s41537-023-00384-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 07/25/2023] [Indexed: 08/14/2023]
Abstract
Negative symptoms (NS) are a core component of schizophrenia affecting community functioning and quality of life. We tested neural correlates of NS considering NS factors and consensus subdomains. We assessed NS using the Clinical Assessment Interview for Negative Symptoms and the Scale for Assessment of Negative Symptoms. Arterial spin labeling was applied to measure resting-state cerebral blood flow (rCBF) in 47 schizophrenia patients and 44 healthy controls. Multiple regression analyses calculated the relationship between rCBF and NS severity. We found an association between diminished expression (DE) and brain perfusion within the cerebellar anterior lobe and vermis, and the pre-, and supplementary motor area. Blunted affect was linked to fusiform gyrus and alogia to fronto-striatal rCBF. In contrast, motivation and pleasure was not associated with rCBF. These results highlight the key role of motor areas for DE. Considering NS factors and consensus subdomains may help identifying specific pathophysiological pathways of NS.
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Affiliation(s)
- Nicole Gangl
- Translational Research Center, University Hospital of Psychiatry and Psychotherapy, Bern, Switzerland.
- Graduate School for Health Sciences, University of Bern, Bern, Switzerland.
| | - Frauke Conring
- Translational Research Center, University Hospital of Psychiatry and Psychotherapy, Bern, Switzerland
- Graduate School for Health Sciences, University of Bern, Bern, Switzerland
| | - Andrea Federspiel
- Translational Research Center, University Hospital of Psychiatry and Psychotherapy, Bern, Switzerland
| | - Roland Wiest
- Support Center of Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, Inselspital, Bern, Switzerland
| | - Sebastian Walther
- Translational Research Center, University Hospital of Psychiatry and Psychotherapy, Bern, Switzerland
| | - Katharina Stegmayer
- Translational Research Center, University Hospital of Psychiatry and Psychotherapy, Bern, Switzerland
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Psychomotor slowing alters gait velocity, cadence, and stride length and indicates negative symptom severity in psychosis. SCHIZOPHRENIA (HEIDELBERG, GERMANY) 2022; 8:116. [PMID: 36585399 PMCID: PMC9803648 DOI: 10.1038/s41537-022-00324-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 12/17/2022] [Indexed: 01/01/2023]
Abstract
Schizophrenia is a severe mental disorder, in which 50% of the patients present with motor abnormalities such as psychomotor slowing. Slow spontaneous gait has been reported in schizophrenia. However, comprehensive objective instrumental assessments of multiple gait conditions are missing. Finally, the specific gait patterns of subjects with psychomotor slowing are still unknown. Therefore, this study aimed to objectively assess multiple gait parameters at different walking conditions in patients with schizophrenia with and without psychomotor slowing. Also, we hypothesised gait impairments to correlate with expert ratings of hypokinetic movement disorders and negative symptoms. We collected gait data (GAITRite®) in 70 patients with psychomotor slowing (SRRS (Salpetriere retardation rating scale) ≥15), 22 non-psychomotor slowed patients (SRRS < 15), and 42 healthy controls. Participants performed four walking conditions (self-selected speed, maximum speed, head reclined, and eyes closed) and six gait parameters were extracted (velocity, cadence, stride length, functional ambulation profile (FAP), and variance of stride length and time). Patients with psychomotor slowing presented slower velocity, lower cadence, and shorter stride length in all walking conditions compared to healthy controls, with the non-slowed patients in an intermediate position (all F > 16.18, all p < 0.001). Secondly, slower velocity was associated with more severe hypokinetic movement disorders and negative symptoms. In conclusion, gait impairments exist in a spectrum with healthy controls on one end and patients with psychomotor slowing on the other end. Patients with psychomotor slowing are specifically impaired when an adaptation of gait patterns is required, contributing to the deleterious effects of sedentary behaviours.
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von Känel S, Nadesalingam N, Alexaki D, Baumann Gama D, Kyrou A, Lefebvre S, Walther S. Measuring catatonia motor behavior with objective instrumentation. Front Psychiatry 2022; 13:880747. [PMID: 36061273 PMCID: PMC9428315 DOI: 10.3389/fpsyt.2022.880747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 07/26/2022] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE Catatonia is a neuropsychiatric syndrome, with important psychomotor features, associated with schizophrenia and other psychiatric disorders. The syndrome comprises multiple symptoms including abnormal motor control, behaviors, volition, and autonomic regulation. Catatonia assessment relies on clinical rating scales and clinicians familiar with the catatonia exam. However, objective instrumentation may aid the detection of catatonia. We aimed to investigate the relationship between movement parameters derived from actigraphy and expert ratings of catatonia symptoms measured by the Bush Francis Catatonia Rating Scale (BFCRS) and the Northoff Catatonia scale (NCS). METHODS Eighty-six acutely ill inpatients with schizophrenia spectrum disorders were assessed with the BFCRS, the NCS, and 24 h continuous actigraphy. Non-wear and sleep periods were removed from the actigraphy data prior to analysis. Associations between total catatonia scores, derived from both BFCRS and NCS, and actigraphy parameters as well as between single BFCRS items and actigraphy parameters were calculated using Spearman's rank correlation and non-parametric ANCOVAs (Quade's ANCOVAs), respectively. RESULTS Both higher BFCRS total scores (r = 0.369, p = 0.006) and NCS total scores (r = 0.384, p = 0.004) were associated with lower activity levels (AL). Higher scores on single BFCRS items such as immobility/stupor or staring were linked to lower AL (immobility/stupor: F = 17.388, p < 0.001, η2 = 0.175; staring: F = 7.849, p = 0.001, η2 = 0.162) and lower metabolic equivalents of task (MET). CONCLUSION Specific catatonia symptoms such as immobility/stupor and staring can be measured with actigraphy. This may aid the detection, staging, and monitoring of catatonia in clinical settings.
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Affiliation(s)
- Sofie von Känel
- Translational Research Center, University Hospital of Psychiatry, University of Bern, Bern, Switzerland
| | - Niluja Nadesalingam
- Translational Research Center, University Hospital of Psychiatry, University of Bern, Bern, Switzerland.,Graduate School for Health Sciences (GHS), University of Bern, Bern, Switzerland
| | | | - Daniel Baumann Gama
- Translational Research Center, University Hospital of Psychiatry, University of Bern, Bern, Switzerland
| | - Alexandra Kyrou
- Translational Research Center, University Hospital of Psychiatry, University of Bern, Bern, Switzerland
| | - Stéphanie Lefebvre
- Translational Research Center, University Hospital of Psychiatry, University of Bern, Bern, Switzerland
| | - Sebastian Walther
- Translational Research Center, University Hospital of Psychiatry, University of Bern, Bern, Switzerland
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Umbricht D, Cheng WY, Lipsmeier F, Bamdadian A, Lindemann M. Deep Learning-Based Human Activity Recognition for Continuous Activity and Gesture Monitoring for Schizophrenia Patients With Negative Symptoms. Front Psychiatry 2020; 11:574375. [PMID: 33192706 PMCID: PMC7525025 DOI: 10.3389/fpsyt.2020.574375] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 08/26/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND We aimed to develop a Human Activity Recognition (HAR) model using a wrist-worn device to assess patient activity in relation to negative symptoms of schizophrenia. METHODS Data were analyzed in a randomized, three-way cross-over, proof-of-mechanism study (ClinicalTrials.gov: NCT02824055) comparing two doses of RG7203 with placebo, given as adjunct to stable antipsychotic treatment in patients with chronic schizophrenia and moderate levels of negative symptoms. Baseline negative symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS) and Brief Negative Symptom Scale (BNSS). Patients were given a GeneActiv™ wrist-worn actigraphy device to wear over a 15-week period. For this analysis, actigraphy data and behavioral and clinical assessments obtained during placebo treatment were used. Motivated behavior was evaluated with a computerized effort-choice task. A trained HAR model was used to classify activity and an activity-time ratio was derived. Gesture events and features were inferred from the HAR-detected activities and the acceleration signal. RESULTS Thirty-three patients were enrolled: mean (±SD) age 36.6 ± 7 years; mean (±SD) baseline PANSS negative symptom factor score 23.0 ± 3.5; and mean (±SD) baseline BNSS total score 36.0 ± 11.5. Activity data were collected for 31 patients with a median monitoring time of 1,859 h per patient, equating to ~11 weeks or 74% monitoring ratio. The trained HAR model demonstrated >95% accuracy in separating ambulatory and stationary activities. A positive correlation was seen between the activity-time ratio and the percent of high-effort choices (Spearman r = 0.58; P = 0.002) in the effort-choice task. Median daily gesture counts correlated negatively with the BNSS total score (Spearman r = -0.44; P = 0.03), specifically with the diminished expression sub-score (Spearman r = -0.42; P = 0.03). Gesture features also correlated negatively with the BNSS total score and diminished expression sub-scores. Activity measures showed similar correlations with PANSS negative symptom factor but did not reach significance. CONCLUSION Our findings support the use of wrist-worn devices to derive activity and gesture-based digital outcome measures for patients with schizophrenia with negative symptoms in a clinical trial setting.
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Affiliation(s)
- Daniel Umbricht
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | - Wei-Yi Cheng
- Roche Innovation Center New York, Roche TCRC Inc, NY, United States
| | - Florian Lipsmeier
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | - Atieh Bamdadian
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | - Michael Lindemann
- Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Basel, Switzerland
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Walther S, van Harten PN, Waddington JL, Cuesta MJ, Peralta V, Dupin L, Foucher JR, Sambataro F, Morrens M, Kubera KM, Pieters LE, Stegmayer K, Strik W, Wolf RC, Hirjak D. Movement disorder and sensorimotor abnormalities in schizophrenia and other psychoses - European consensus on assessment and perspectives. Eur Neuropsychopharmacol 2020; 38:25-39. [PMID: 32713718 DOI: 10.1016/j.euroneuro.2020.07.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 06/06/2020] [Accepted: 07/06/2020] [Indexed: 02/06/2023]
Abstract
Over the last three decades, movement disorder as well as sensorimotor and psychomotor functioning in schizophrenia (SZ) and other psychoses has gained greater scientific and clinical relevance as an intrinsic component of the disease process of psychotic illness; this extends to early psychosis prediction, early detection of motor side effects of antipsychotic medication, clinical outcome monitoring, treatment of psychomotor syndromes (e.g. catatonia), and identification of new targets for non-invasive brain stimulation. In 2017, a systematic cooperation between working groups interested in movement disorder and sensorimotor/psychomotor functioning in psychoses was initiated across European universities. As a first step, the members of this group would like to introduce and define the theoretical aspects of the sensorimotor domain in SZ and other psychoses. This consensus paper is based on a synthesis of scientific evidence, good clinical practice and expert opinions that were discussed during recent conferences hosted by national and international psychiatric associations. While reviewing and discussing the recent theoretical and experimental work on neural mechanisms and clinical implications of sensorimotor behavior, we here seek to define the key principles and elements of research on movement disorder and sensorimotor/psychomotor functioning in psychotic illness. Finally, the members of this European group anticipate that this consensus paper will stimulate further multimodal and prospective studies on hypo- and hyperkinetic movement disorders and sensorimotor/psychomotor functioning in SZ and other psychotic disorders.
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Affiliation(s)
- Sebastian Walther
- Translational Research Center, University Hospital of Psychiatry, University of Bern, Switzerland
| | - Peter N van Harten
- Psychiatric Center GGz Centraal, Amersfoort, The Netherlands; Department of Psychiatry, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, the Netherlands
| | - John L Waddington
- School of Pharmacy and Biomolecular Sciences, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Manuel J Cuesta
- Department of Psychiatry, Complejo Hospitalario de Navarra, Spain. Instituto de Investigación Sanitaria de Navarra (IdisNa), Spain
| | - Victor Peralta
- Mental Health Department, Servicio Navarro de Salud, Pamplona, Spain, Navarra Institute for Health Research, IdiSNA, Pamplona, Spain
| | - Lucile Dupin
- Institut de Psychiatrie et Neurosciences de Paris, INSERM U1266, Université de Paris, Paris, France
| | - Jack R Foucher
- ICube - CNRS UMR 7357, Neurophysiology, FMTS, University of Strasbourg, Strasbourg, France; CEMNIS - Noninvasive Neuromodulation Center, University Hospital Strasbourg, Strasbourg, France
| | - Fabio Sambataro
- Department of Neuroscience (DNS), University of Padova, Padova, Italy; Padova Neuroscience Center, University of Padova, Padua, Italy
| | - Manuel Morrens
- Department of Psychiatry, University Psychiatric Center Duffel, Duffel, Belgium; Department of Psychiatry, Collaborative Antwerp Psychiatric Research Institute (CAPRI), Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium
| | - Katharina M Kubera
- Center for Psychosocial Medicine, Department of General Psychiatry, Heidelberg University, Heidelberg, Germany
| | - Lydia E Pieters
- Psychiatric Center GGz Centraal, Amersfoort, The Netherlands; Department of Psychiatry, School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, the Netherlands
| | - Katharina Stegmayer
- Translational Research Center, University Hospital of Psychiatry, University of Bern, Switzerland
| | - Werner Strik
- Translational Research Center, University Hospital of Psychiatry, University of Bern, Switzerland
| | - R Christian Wolf
- Center for Psychosocial Medicine, Department of General Psychiatry, Heidelberg University, Heidelberg, Germany
| | - Dusan Hirjak
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
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8
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Sambataro F, Fritze S, Rashidi M, Topor CE, Kubera KM, Wolf RC, Hirjak D. Moving forward: distinct sensorimotor abnormalities predict clinical outcome after 6 months in patients with schizophrenia. Eur Neuropsychopharmacol 2020; 36:72-82. [PMID: 32522386 DOI: 10.1016/j.euroneuro.2020.05.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Revised: 04/28/2020] [Accepted: 05/04/2020] [Indexed: 01/24/2023]
Abstract
Despite substantial efforts in the last decades, objective measures that can predict clinical outcome in patients with schizophrenia (SZ) after an acute psychotic episode are still lacking. Here, we introduced a comprehensive assessment of sensorimotor function to predict mid-term clinical outcome following an acute psychotic episode. This naturalistic follow-up of 43 patients with DSM-IV-TR diagnosis of SZ examined sensorimotor abnormalities (i.e. Neurological Soft Signs (NSS), parkinsonism, akathisia, catatonia and acute dyskinesia), psychopathology, cognition and psychosocial functioning using well-established instruments. A collection of statistical methods was used to examine the relationship between sensorimotor domain, psychopathology, cognition and psychosocial functioning. We also tested the clinical feasibility of this relationship when predicting clinical outcome after an acute psychotic episode. Longitudinal data were collected on 43 individuals after a follow-up period of >6 months. At follow-up, patients showed significantly reduced general symptom severity, as well as decreased levels of NSS, parkinsonism and catatonia. Further, NSS scores at baseline predicted PANSS negative scores and cognitive functioning at baseline. Finally, NSS scores at baseline predicted symptom change (reduction of PANSS positive and negative scores) at follow-up. In conclusion, our results suggest that NSS are significant predictors of poor clinical outcome in SZ at baseline and >6 months after an acute psychotic episode. These findings propose sensorimotor domain as state biomarker of SZ and support its predictive power with respect to treatment outcome.
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Affiliation(s)
- Fabio Sambataro
- Department of Neuroscience (DNS), University of Padova, Padova, Italy
| | - Stefan Fritze
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, D-68159, Germany
| | - Mahmoud Rashidi
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, D-68159, Germany; Center for Psychosocial Medicine, Department of General Psychiatry, Heidelberg University, Germany
| | - Cristina E Topor
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, D-68159, Germany
| | - Katharina M Kubera
- Center for Psychosocial Medicine, Department of General Psychiatry, Heidelberg University, Germany
| | - Robert C Wolf
- Center for Psychosocial Medicine, Department of General Psychiatry, Heidelberg University, Germany
| | - Dusan Hirjak
- Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, D-68159, Germany.
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Osborne KJ, Walther S, Shankman SA, Mittal VA. Psychomotor Slowing in Schizophrenia: Implications for Endophenotype and Biomarker Development. Biomark Neuropsychiatry 2020; 2:100016. [PMID: 33738459 PMCID: PMC7963400 DOI: 10.1016/j.bionps.2020.100016] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Motor abnormalities (e.g., dyskinesia, psychomotor slowing, neurological soft signs) are core features of schizophrenia that occur independent of drug treatment and are associated with the genetic vulnerability and pathophysiology for the illness. Among this list, psychomotor slowing in particular is one of the most consistently observed and robust findings in the field. Critically, psychomotor slowing may serve as a uniquely promising endophenotype and/or biomarker for schizophrenia considering it is frequently observed in those with genetic vulnerability for the illness, predicts transition in subjects at high-risk for the disorder, and is associated with symptoms and recovery in patients. The purpose of the present review is to provide an overview of the history of psychomotor slowing in psychosis, discuss its possible neural underpinnings, and review the current literature supporting slowing as a putative endophenotype and/or biomarker for the illness. This review summarizes substantial evidence from a diverse array of methodologies and research designs that supports the notion that psychomotor slowing not only reflects genetic vulnerability, but is also sensitive to disease processes and the pathophysiology of the illness. Furthermore, there are unique deficits across the cognitive (prefix "psycho") and motor execution (root word "motor") aspects of slowing, with cognitive processes such as planning and response selection being particularly affected. These findings suggest that psychomotor slowing may serve as a promising endophenotype and biomarker for schizophrenia that may prove useful for identifying individuals at greatest risk and tracking the course of the illness and recovery.
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Affiliation(s)
- K. Juston Osborne
- Northwestern University, Department of Psychology, Evanston, IL, USA
| | - Sebastian Walther
- University of Bern, University Hospital of Psychiatry, Translational Research Center, Bern, Switzerland
| | - Stewart A. Shankman
- Northwestern University, Department of Psychology, Evanston, IL, USA
- Northwestern University, Department of Psychiatry, Chicago, IL, USA
| | - Vijay A. Mittal
- Northwestern University, Department of Psychology, Evanston, IL, USA
- Northwestern University, Department of Psychiatry, Chicago, IL, USA
- Northwestern University, Department of Psychiatry, Institute for Policy Research, Department of Medical Social Sciences, Institute for Innovations in Developmental Sciences (DevSci), Evanston, Chicago, IL, USA
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10
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Servaas MN, Kos C, Gravel N, Renken RJ, Marsman JBC, van Tol MJ, Aleman A. Rigidity in Motor Behavior and Brain Functioning in Patients With Schizophrenia and High Levels of Apathy. Schizophr Bull 2019; 45:542-551. [PMID: 30053198 PMCID: PMC6483574 DOI: 10.1093/schbul/sby108] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The aim of this study was to investigate whether apathy in schizophrenia is associated with rigidity in behavior and brain functioning. To this end, we studied associations between variability in dynamic functional connectivity (DFC) in relevant functional brain networks, apathy, and variability in physical activity in schizophrenia. Thirty-one patients with schizophrenia, scoring high on apathy, were included and wore an actigraph. Activity variability was calculated on the activity counts using the root of the Mean Squared Successive Difference (MSSD). Furthermore, we calculated DFC on resting-state data as phase interactions between blood oxygen-level dependent (BOLD) signals of 270 brain regions per volume. Variability (MSSD) in DFC was calculated for 3 networks, including the default-mode network (DMN), frontoparietal network, and salience-reward network (SRN). Finally, we calculated correlations between these DFC estimates and apathy and activity variability. First, lower activity variability was associated with higher levels of apathy. Second, higher levels of apathy were associated with lower variability in DFC in the DMN and SRN. Third, higher activity variability was associated with higher variability in DFC in the SRN. In conclusion, patients with schizophrenia and more severe levels of apathy showed less variability in their physical activity and more rigid functional brain network behavior in the DMN and SRN. These networks have been shown relevant for self-reflection, mental simulation, and reward processing, processes that are pivotal for self-initiated goal-directed behavior. Functional rigidity of these networks may therefore contribute to reduced goal-directed behavior, which is characteristic for these patients.
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Affiliation(s)
- Michelle N Servaas
- Neuroimaging Center, Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Claire Kos
- Neuroimaging Center, Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Nicolás Gravel
- Neuroimaging Center, Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Remco J Renken
- Neuroimaging Center, Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Jan-Bernard C Marsman
- Neuroimaging Center, Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Marie-José van Tol
- Neuroimaging Center, Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - André Aleman
- Neuroimaging Center, Department of Neuroscience, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- Department of Psychology, University of Groningen, Groningen, The Netherlands
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11
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Motor activity patterns in acute schizophrenia and other psychotic disorders can be differentiated from bipolar mania and unipolar depression. Psychiatry Res 2018; 270:418-425. [PMID: 30312969 DOI: 10.1016/j.psychres.2018.10.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 10/01/2018] [Accepted: 10/02/2018] [Indexed: 12/22/2022]
Abstract
The purpose of this study was to compare 24-h motor activity patterns between and within three groups of acutely admitted inpatients with schizophrenia and psychotic disorders (n = 28), bipolar mania (n = 18) and motor-retarded unipolar depression (n = 25) and one group of non-hospitalized healthy individuals (n = 28). Motor activity was measured by wrist actigraphy, and analytical approaches using linear and non-linear variability and irregularity measures were undertaken. In between-group comparisons, the schizophrenia group showed more irregular activity patterns than depression cases and healthy individuals. The schizophrenia and mania cases were clinically similar with respect to high prevalence of psychotic symptoms. Although they could not be separated by a formal statistical test, the schizophrenia cases showed more normal amplitudes in morning to evening mean activity and activity variability. Schizophrenia constituted an independent entity in terms of motor activation that could be distinguished from the other diagnostic groups of psychotic and non-psychotic affective disorders. Despite limitations such as small subgroups, short recordings and confounding effects of medication/hospitalization, these results suggest that detailed temporal analysis of motor activity patterns can identify similarities and differences between prevalent functional psychiatric disorders. For this purpose, irregularity measures seem particularly useful to characterize psychotic symptoms and should be explored in larger samples with longer-term recordings, while searching for underlying mechanisms of motor activity disturbances.
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Meyer N, Kerz M, Folarin A, Joyce DW, Jackson R, Karr C, Dobson R, MacCabe J. Capturing Rest-Activity Profiles in Schizophrenia Using Wearable and Mobile Technologies: Development, Implementation, Feasibility, and Acceptability of a Remote Monitoring Platform. JMIR Mhealth Uhealth 2018; 6:e188. [PMID: 30377146 PMCID: PMC6234334 DOI: 10.2196/mhealth.8292] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 10/19/2017] [Accepted: 06/21/2018] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND There is growing interest in the potential for wearable and mobile devices to deliver clinically relevant information in real-world contexts. However, there is limited information on their acceptability and barriers to long-term use in people living with psychosis. OBJECTIVE This study aimed to describe the development, implementation, feasibility, acceptability, and user experiences of the Sleepsight platform, which harnesses consumer wearable devices and smartphones for the passive and unobtrusive capture of sleep and rest-activity profiles in people with schizophrenia living in their homes. METHODS A total of 15 outpatients with a diagnosis of schizophrenia used a consumer wrist-worn device and smartphone to continuously and remotely gather rest-activity profiles over 2 months. Once-daily sleep and self-rated symptom diaries were also collected via a smartphone app. Adherence with the devices and smartphone app, end-of-study user experiences, and agreement between subjective and objective sleep measures were analyzed. Thresholds for acceptability were set at a wear time or diary response rate of 70% or greater. RESULTS Overall, 14 out of 15 participants completed the study. In individuals with a mild to moderate symptom severity at baseline (mean total Positive and Negative Syndrome Scale score 58.4 [SD 14.4]), we demonstrated high rates of engagement with the wearable device (all participants meeting acceptability criteria), sleep diary, and symptom diary (93% and 86% meeting criteria, respectively), with negative symptoms being associated with lower diary completion rate. The end-of-study usability and acceptability questionnaire and qualitative analysis identified facilitators and barriers to long-term use, and paranoia with study devices was not a significant barrier to engagement. Comparison between sleep diary and wearable estimated sleep times showed good correspondence (ρ=0.50, P<.001). CONCLUSIONS Extended use of wearable and mobile technologies are acceptable to people with schizophrenia living in a community setting. In the future, these technologies may allow predictive, objective markers of clinical status, including early markers of impending relapse.
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Affiliation(s)
- Nicholas Meyer
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- South London and Maudsley National Health Service Foundation Trust, Bethlem Royal Hospital, Beckenham, Kent, United Kingdom
| | - Maximilian Kerz
- Department of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Amos Folarin
- Department of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Dan W Joyce
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- South London and Maudsley National Health Service Foundation Trust, Bethlem Royal Hospital, Beckenham, Kent, United Kingdom
| | - Richard Jackson
- Department of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - Chris Karr
- Audacious Software, Chicago, IL, United States
- Center for Behavioural Intervention Technologies, Northwestern University, Chicago, IL, United States
| | - Richard Dobson
- Department of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | - James MacCabe
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
- South London and Maudsley National Health Service Foundation Trust, Bethlem Royal Hospital, Beckenham, Kent, United Kingdom
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Motion energy analysis reveals altered body movement in youth at risk for psychosis. Schizophr Res 2018; 200:35-41. [PMID: 28587814 PMCID: PMC5712481 DOI: 10.1016/j.schres.2017.05.035] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2017] [Revised: 05/23/2017] [Accepted: 05/26/2017] [Indexed: 12/29/2022]
Abstract
BACKGROUND Growing evidence suggests that movement abnormalities occur prior to the onset of psychosis. Innovations in technology and software provide the opportunity for a fine-tuned and sensitive measurement of observable behavior that may be particularly useful to detecting the subtle movement aberrations present during the prodromal period. METHODS In the present study, 54 youth at ultrahigh risk (UHR) for psychosis and 62 healthy controls participated in structured clinical interviews to assess for an UHR syndrome. The initial 15min of the baseline clinical interview was assessed using Motion Energy Analysis (MEA) providing frame-by-frame measures of total movement, amplitude, speed, and variability of both head and body movement separately. RESULTS Result showed region-specific group differences such that there were no differences in head movement but significant differences in body movement. Specifically, the UHR group showed greater total body movement and speed of body movements, and lower variation in body movement compared to healthy controls. However, there were no significant associations with positive, negative or disorganized symptom domains. CONCLUSION This study represents an innovative perspective on gross motor function in the UHR group. Importantly, the automated approach used in this study provides a sensitive and objective measure of body movement abnormalities, potentially guiding novel assessment and prevention of symptom development in those at risk for psychosis.
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Siddiqui I, Remington G, Fervaha G, Fletcher PJ, Voineskos AN, Saperia S, Zakzanis KK, Foussias G. Objective investigation of activity preference in schizophrenia: A pilot study. Psychiatry Res 2018; 267:551-559. [PMID: 29980136 DOI: 10.1016/j.psychres.2018.05.039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 03/23/2018] [Accepted: 05/15/2018] [Indexed: 11/29/2022]
Abstract
Amotivation and reduced goal-directed activity engagement are prominent features of schizophrenia. Previous investigations of patients' activities have relied on accounts of daily living activities, rather than objective measures. This study used wireless motion capture to objectively evaluate activity preference when individuals are provided an explicit choice between an active versus passive engagement option. Twenty outpatients with schizophrenia and twenty matched healthy controls completed the Activity Preference Task, in which participants play a motion-based game (active) or watch a film (passive), and were administered clinical and cognitive assessments. Schizophrenia participants' duration, intensity, and persistence of active engagement were associated with apathy and community functioning. No group differences emerged from comparisons of task measures; however, exploratory cluster analysis identified a distinct subgroup of schizophrenia patients with reduced engagement and increased apathy compared to other patients and controls. The Task provides a means of quantifying activity engagement, which may be particularly valuable given the lack of objective measures for intrinsically motivated behaviours. Our initial findings suggest that schizophrenia patients as a group are equally inclined as healthy individuals towards actively engaging activities when presented an explicit choice, but such provision may be insufficient for initiation and maintenance of functional behaviours among amotivated patients.
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Affiliation(s)
- Ishraq Siddiqui
- Schizophrenia Division and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, Ontario M5T 1R8, Canada.; Institute of Medical Science, Faculty of Medicine, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada..
| | - Gary Remington
- Schizophrenia Division and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, Ontario M5T 1R8, Canada.; Institute of Medical Science, Faculty of Medicine, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.; Department of Psychiatry, University of Toronto, 250 College St., Toronto, Ontario M5T 1R8, Canada
| | - Gagan Fervaha
- Schizophrenia Division and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, Ontario M5T 1R8, Canada.; Institute of Medical Science, Faculty of Medicine, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada
| | - Paul J Fletcher
- Department of Psychiatry, University of Toronto, 250 College St., Toronto, Ontario M5T 1R8, Canada; Preclinical Research and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, Ontario M5T 1R8, Canada; Department of Psychology, University of Toronto, Sidney Smith Hall, 100 St. George St., Toronto, Ontario M5S 3G3, Canada
| | - Aristotle N Voineskos
- Schizophrenia Division and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, Ontario M5T 1R8, Canada.; Institute of Medical Science, Faculty of Medicine, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.; Department of Psychiatry, University of Toronto, 250 College St., Toronto, Ontario M5T 1R8, Canada
| | - Sarah Saperia
- Schizophrenia Division and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, Ontario M5T 1R8, Canada
| | - Konstantine K Zakzanis
- Department of Psychology, University of Toronto Scarborough, 1265 Military Trail, Toronto, Ontario M1C 1A4, Canada
| | - George Foussias
- Schizophrenia Division and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St., Toronto, Ontario M5T 1R8, Canada.; Institute of Medical Science, Faculty of Medicine, University of Toronto, Medical Sciences Building, 1 King's College Circle, Toronto, Ontario M5S 1A8, Canada.; Department of Psychiatry, University of Toronto, 250 College St., Toronto, Ontario M5T 1R8, Canada
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Strik W, Stegmayer K, Walther S, Dierks T. Systems Neuroscience of Psychosis: Mapping Schizophrenia Symptoms onto Brain Systems. Neuropsychobiology 2018; 75:100-116. [PMID: 29258073 DOI: 10.1159/000485221] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Schizophrenia research has been in a deadlock for many decades. Despite important advances in clinical treatment, there are still major concerns regarding long-term psychosocial reintegration and disease management, biological heterogeneity, unsatisfactory predictors of individual course and treatment strategies, and a confusing variety of controversial theories about its etiology and pathophysiological mechanisms. In the present perspective on schizophrenia research, we first discuss a methodological pitfall in contemporary schizophrenia research inherent in the attempt to link mental phenomena with the brain: we claim that the time-honored phenomenological method of defining mental symptoms should not be contaminated with the naturalistic approach of modern neuroscience. We then describe our Systems Neuroscience of Psychosis (SyNoPsis) project, which aims to overcome this intrinsic problem of psychiatric research. Considering schizophrenia primarily as a disorder of interindividual communication, we developed a neurobiologically informed semiotics of psychotic disorders, as well as an operational clinical rating scale. The novel psychopathology allows disentangling the clinical manifestations of schizophrenia into behavioral domains matching the functions of three well-described higher-order corticobasal brain systems involved in interindividual human communication, namely, the limbic, associative, and motor loops, including their corticocortical sensorimotor connections. The results of several empirical studies support the hypothesis that the proposed three-dimensional symptom structure, segregated into the affective, the language, and the motor domain, can be specifically mapped onto structural and functional abnormalities of the respective brain systems. New pathophysiological hypotheses derived from this brain system-oriented approach have helped to develop and improve novel treatment strategies with noninvasive brain stimulation and practicable clinical parameters. In clinical practice, the novel psychopathology allows confining the communication deficits of the individual patient, shifting attention from the symptoms to the intact resources. We have studied this approach and observed important advantages for therapeutic alliances, personalized treatment, and de-escalation strategies. Future studies will further conjoin clinical definitions of psychotic symptoms with brain structures and functions, and disentangle structural and functional deficit patterns within these systems to identify neurobiologically distinct subsyndromes. Neurobiologically homogeneous patient groups may provide new momentum for treatment research. Finally, lessons learned from schizophrenia research may contribute to developing a comprehensive perspective on human experience and behavior that integrates methodologically distinct, but internally consistent, insights from humanities and neuroscience.
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Fasmer EE, Fasmer OB, Berle JØ, Oedegaard KJ, Hauge ER. Graph theory applied to the analysis of motor activity in patients with schizophrenia and depression. PLoS One 2018; 13:e0194791. [PMID: 29668743 PMCID: PMC5905887 DOI: 10.1371/journal.pone.0194791] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 03/10/2018] [Indexed: 12/11/2022] Open
Abstract
Depression and schizophrenia are defined only by their clinical features, and diagnostic separation between them can be difficult. Disturbances in motor activity pattern are central features of both types of disorders. We introduce a new method to analyze time series, called the similarity graph algorithm. Time series of motor activity, obtained from actigraph registrations over 12 days in depressed and schizophrenic patients, were mapped into a graph and we then applied techniques from graph theory to characterize these time series, primarily looking for changes in complexity. The most marked finding was that depressed patients were found to be significantly different from both controls and schizophrenic patients, with evidence of less regularity of the time series, when analyzing the recordings with one hour intervals. These findings support the contention that there are important differences in control systems regulating motor behavior in patients with depression and schizophrenia. The similarity graph algorithm we have described can easily be applied to the study of other types of time series.
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Affiliation(s)
| | - Ole Bernt Fasmer
- Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Medicine, Section for Psychiatry, University of Bergen, Bergen, Norway
- K.G. Jebsen Centre for Research on Neuropsychiatric Disorders, Bergen, Norway
- * E-mail:
| | - Jan Øystein Berle
- Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Medicine, Section for Psychiatry, University of Bergen, Bergen, Norway
| | - Ketil J. Oedegaard
- Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
- Department of Clinical Medicine, Section for Psychiatry, University of Bergen, Bergen, Norway
- K.G. Jebsen Centre for Research on Neuropsychiatric Disorders, Bergen, Norway
| | - Erik R. Hauge
- Division of Psychiatry, Haukeland University Hospital, Bergen, Norway
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Stegmayer K, Walther S, van Harten P. Tardive Dyskinesia Associated with Atypical Antipsychotics: Prevalence, Mechanisms and Management Strategies. CNS Drugs 2018; 32:135-147. [PMID: 29427000 DOI: 10.1007/s40263-018-0494-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
All antipsychotics, including the atypical antipsychotics (AAPs), may cause tardive dyskinesia (TD), a potentially irreversible movement disorder, the pathophysiology of which is currently unknown. The prevention and treatment of TD remain major challenges for clinicians. We conducted a PubMed search to review the prevalence and etiology of and management strategies for TD associated with AAPs. TD prevalence rates varied substantially between studies, with an estimated prevalence of around 20% in patients using AAPs. The risk of TD is lower with AAPs than with typical antipsychotics (TAPs) but remains a problem because AAPs are increasingly being prescribed. Important risk factors associated with TD include the duration of antipsychotic use, age, and ethnicity other than Caucasian. Theories about the etiology of TD include supersensitivity of the dopamine receptors and oxidative stress, but other neurotransmitters and factors are probably involved. Studies concerning the management of TD have considerable methodological limitations. Thus, recommendations for the management of TD are based on a few trials and clinical experience, and no general guidelines for the management of TD can be established. The best management strategy remains prevention. Caution is required when prescribing antipsychotics, and regular screening is needed for early detection of TD. Other strategies may include reducing the AAP dosage, switching to clozapine, or administering vesicular monoamine transporter (VMAT)-2 inhibitors. In severe cases, local injections of botulinum toxin or deep brain stimulation may be considered. More clinical trials in larger samples are needed to gather valid information on the effect of interventions targeting TD.
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Affiliation(s)
- Katharina Stegmayer
- University Hospital of Psychiatry, Bolligenstrasse 111, 3060, Bern, Switzerland.
| | - Sebastian Walther
- University Hospital of Psychiatry, Bolligenstrasse 111, 3060, Bern, Switzerland
| | - Peter van Harten
- Psychiatric Centre GGz Centraal, Innova, Amersfoort, The Netherlands.,School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
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18
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Schäppi L, Stegmayer K, Viher PV, Walther S. Distinct Associations of Motor Domains in Relatives of Schizophrenia Patients-Different Pathways to Motor Abnormalities in Schizophrenia? Front Psychiatry 2018; 9:129. [PMID: 29740353 PMCID: PMC5924816 DOI: 10.3389/fpsyt.2018.00129] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/26/2018] [Indexed: 12/25/2022] Open
Abstract
INTRODUCTION Aberrant motor function is an integral part of schizophrenia. In fact, abnormalities are frequently found in patients, in populations at risk, and in unaffected relatives. Motor abnormalities are suspected to be relevant for the clinical outcome and could probably predict the conversion from at-risk individuals to schizophrenia. Furthermore, motor function has been argued as endophenotype of the disorder. Yet, which particular motor domain may classify as a potential endophenotype is unknown. We aimed to compare schizophrenia patients, unaffected first-degree relatives and healthy controls for different motor domains. We expected impairments in all domains in patients and in some domains in relatives. METHOD We included 43 schizophrenia patients, 34 unaffected first-degree relatives of schizophrenia patients, and 29 healthy control subjects, matched for age, gender, and education level. We compared motor function of four motor domains between the groups. The domains comprise neurological soft signs (NSS), abnormal involuntary movements (dyskinesia), Parkinsonism, and fine motor function including simple [finger tapping (FT)] and complex fine motor function, (i.e., dexterity as measured with the coin rotation test). Furthermore, we tested the association of motor function of the four domains with working memory, frontal lobe function, and nonverbal intelligence for each group separately using within-group bivariate correlations. RESULTS Schizophrenia patients showed poorer motor function in all tested domains compared to healthy controls. First-degree relatives had intermediate ratings with aberrant function in two motor domains. In detail, relatives had significantly more NSS and performed poorer in the FT task than controls. In contrast, complex fine motor function was intact in relatives. Relatives did not differ from controls in dyskinesia or Parkinsonism severity. DISCUSSION Taken together, schizophrenia patients have motor abnormalities in all tested domains. Thus, motor abnormalities are a key element of the disorder. Likewise, first-degree relatives presented motor deficits in two domains. A clear difference between relatives and healthy controls was found for NSS and FT. Thus, NSS and FT may be potential markers of vulnerability for schizophrenia. The lack of association between genetic risk and dyskinesia or Parkinsonism suggests distinct pathobiological mechanisms in the various motor abnormalities in schizophrenia.
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Affiliation(s)
- Lea Schäppi
- University Hospital of Psychiatry, University of Bern, Bern, Switzerland
| | | | - Petra V Viher
- University Hospital of Psychiatry, University of Bern, Bern, Switzerland
| | - Sebastian Walther
- University Hospital of Psychiatry, University of Bern, Bern, Switzerland
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Lincoln TM, Riehle M, Pillny M, Helbig-Lang S, Fladung AK, Hartmann-Riemer M, Kaiser S. Using Functional Analysis as a Framework to Guide Individualized Treatment for Negative Symptoms. Front Psychol 2017; 8:2108. [PMID: 29259567 PMCID: PMC5723417 DOI: 10.3389/fpsyg.2017.02108] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 11/17/2017] [Indexed: 12/19/2022] Open
Abstract
Although numerous interventions are available for negative symptoms, outcomes have been unsatisfactory with pharmacological and psychological interventions producing changes of only limited clinical significance. Here, we argue that because negative symptoms occur as a complex syndrome caused and maintained by numerous factors that vary between individuals they are unlikely to be treated effectively by the present "one size fits all" approaches. Instead, a well-founded selection of those interventions relevant to each individual is needed to optimize both the efficiency and the efficacy of existing approaches. The concept of functional analysis (FA) can be used to structure existing knowledge so that it can guide individualized treatment planning. FA is based on stimulus-response learning mechanisms taking into account the characteristics of the organism that contribute to the responses, their consequences and the contingency with which consequences are tied to the response. FA can thus be flexibly applied to the level of individual patients to understand the factors causing and maintaining negative symptoms and derive suitable interventions. In this article we will briefly introduce the concept of FA and demonstrate-exemplarily-how known psychological and biological correlates of negative symptoms can be incorporated into its framework. We then outline the framework's implications for individual assessment and treatment. Following the logic of FA, we argue that a detailed assessment is needed to identify the key factors causing or maintaining negative symptoms for each individual patient. Interventions can then be selected according to their likelihood of changing these key factors and need to take interactions between different factors into account. Supplementary case vignettes exemplify the usefulness of functional analysis for individual treatment planning. Finally, we discuss and point to avenues for future research guided by this model.
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Affiliation(s)
- Tania M. Lincoln
- Clinical Psychology and Psychotherapy, Faculty of Psychology and Movement Sciences, Institute of Psychology, Universität Hamburg, Hamburg, Germany
| | - Marcel Riehle
- Clinical Psychology and Psychotherapy, Faculty of Psychology and Movement Sciences, Institute of Psychology, Universität Hamburg, Hamburg, Germany
| | - Matthias Pillny
- Clinical Psychology and Psychotherapy, Faculty of Psychology and Movement Sciences, Institute of Psychology, Universität Hamburg, Hamburg, Germany
| | - Sylvia Helbig-Lang
- Clinical Psychology and Psychotherapy, Faculty of Psychology and Movement Sciences, Institute of Psychology, Universität Hamburg, Hamburg, Germany
| | - Anne-Katharina Fladung
- Clinical Psychology and Psychotherapy, Faculty of Psychology and Movement Sciences, Institute of Psychology, Universität Hamburg, Hamburg, Germany
| | - Matthias Hartmann-Riemer
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland
| | - Stefan Kaiser
- Adult Psychiatry Division, Department of Mental Health and Psychiatry, Geneva University Hospital, Geneva, Switzerland
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Abstract
PURPOSE OF REVIEW Motor abnormalities are an intrinsic feature of psychosis. Neurological soft signs, Parkinsonism, dyskinesia, and other motor phenomena are frequently observed in subjects at clinical or genetic risk for psychosis as well as first-episode patients, chronic patients. Here, we review the most recent literature on motor assessments and pathophysiology in psychosis. RECENT FINDINGS Instrumental measures of fine motor performance, balance, spontaneous motor activity, and gesture indicated motor abnormalities in subjects at risk and across stages of schizophrenia. Motor phenomena are associated with distinct symptom dimensions and may indicate poor outcomes. Neuroimaging studies demonstrated altered neural maturation within critical motor networks in subjects at risk. Furthermore, specific categories of motor dysfunction were associated with distinct structural and functional alterations in the motor system in schizophrenia. Motor abnormalities provide a unique window into the pathobiology of psychosis and have the potential to guide screening, staging, and outcome prediction.
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Affiliation(s)
- Sebastian Walther
- Translational Research Center, University Hospital of Psychiatry, University of Bern, Murtenstrasse 21, 3008, Bern, Switzerland.
| | - Vijay A Mittal
- Department of Psychology, Northwestern University, Evanston, IL, USA.,Department of Psychiatry, Northwestern University, Evanston, IL, USA.,Department of Medical Social Sciences, Northwestern University, Evanston, IL, USA.,Institute for Policy Research, Northwestern University, Evanston, IL, USA.,Institute for Developmental Science, Northwestern University, Evanston, IL, USA
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Walther S, Schäppi L, Federspiel A, Bohlhalter S, Wiest R, Strik W, Stegmayer K. Resting-State Hyperperfusion of the Supplementary Motor Area in Catatonia. Schizophr Bull 2017; 43:972-981. [PMID: 27729486 PMCID: PMC5581902 DOI: 10.1093/schbul/sbw140] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Catatonia is a psychomotor syndrome that not only frequently occurs in the context of schizophrenia but also in other conditions. The neural correlates of catatonia remain unclear due to small-sized studies. We therefore compared resting-state cerebral blood flow (rCBF) and gray matter (GM) density between schizophrenia patients with current catatonia and without catatonia and healthy controls. We included 42 schizophrenia patients and 41 controls. Catatonia was currently present in 15 patients (scoring >2 items on the Bush Francis Catatonia Rating Scale screening). Patients did not differ in antipsychotic medication or positive symptoms. We acquired whole-brain rCBF using arterial spin labeling and GM density. We compared whole-brain perfusion and GM density over all and between the groups using 1-way ANCOVAs (F and T tests). We found a group effect (F test) of rCBF within bilateral supplementary motor area (SMA), anterior cingulate cortex, dorsolateral prefrontal cortex, left interior parietal lobe, and cerebellum. T tests indicated 1 cluster (SMA) to be specific to catatonia. Moreover, catatonia of excited and retarded types differed in SMA perfusion. Furthermore, increased catatonia severity was associated with higher perfusion in SMA. Finally, catatonia patients had a distinct pattern of GM density reduction compared to controls with prominent GM loss in frontal and insular cortices. SMA resting-state hyperperfusion is a marker of current catatonia in schizophrenia. This is highly compatible with a dysregulated motor system in catatonia, particularly affecting premotor areas. Moreover, SMA perfusion was differentially altered in retarded and excited catatonia subtypes, arguing for distinct pathobiology.
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Affiliation(s)
- Sebastian Walther
- Translational Research Center, University Hospital of Psychiatry, Bern, Switzerland;,To whom correspondence should be addressed; Translational Research Center, University Hospital of Psychiatry, Bolligenstrasse 111, 3060 Bern, Switzerland; tel: +41-31-930-9483, fax: +41-31-930-9404, e-mail:
| | - Lea Schäppi
- Translational Research Center, University Hospital of Psychiatry, Bern, Switzerland
| | - Andrea Federspiel
- Translational Research Center, University Hospital of Psychiatry, Bern, Switzerland
| | - Stephan Bohlhalter
- Neurology and Neurorehabilitation Center, Luzerner Kantonsspital, Lucerne, Switzerland
| | - Roland Wiest
- Support Center of Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, Inselspital, Bern, Switzerland
| | - Werner Strik
- Translational Research Center, University Hospital of Psychiatry, Bern, Switzerland
| | - Katharina Stegmayer
- Translational Research Center, University Hospital of Psychiatry, Bern, Switzerland
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Kaiser S, Lyne J, Agartz I, Clarke M, Mørch-Johnsen L, Faerden A. Individual negative symptoms and domains - Relevance for assessment, pathomechanisms and treatment. Schizophr Res 2017; 186:39-45. [PMID: 27453425 DOI: 10.1016/j.schres.2016.07.013] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 07/07/2016] [Accepted: 07/15/2016] [Indexed: 12/12/2022]
Abstract
The negative symptoms of schizophrenia can be divided into two domains. Avolition/apathy includes the individual symptoms of avolition, asociality and anhedonia. Diminished expression includes blunted affect and alogia. Until now, causes and treatment of negative symptoms have remained a major challenge, which is partially related to the focus on negative symptoms as a broad entity. Here, we propose that negative symptoms may become more tractable when the different domains and individual symptoms are taken into account. There is now increasing evidence that the relationship with clinical variables - in particular outcome - differs between the domains of avolition/apathy and diminished expression. Regarding models of negative symptom formation, those relevant to avolition/apathy are now converging on processes underlying goal-directed behavior and dysfunctions of the reward system. In contrast, models of the diminished expression domains are only beginning to emerge. The aim of this article is to review the specific clinical, behavioral and neural correlates of individual symptoms and domains as a better understanding of these areas may facilitate specific treatment approaches.
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Affiliation(s)
- Stefan Kaiser
- Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Zurich, Switzerland.
| | - John Lyne
- Royal College of Surgeons in Ireland, 123 St. Stephen's Green, Dublin 2, Ireland; North Dublin Mental Health Services, Ashlin Centre, Beaumont Road, Dublin 9, Ireland; Dublin and East Treatment and Early Care Team (DETECT) Services, Dublin, Ireland
| | - Ingrid Agartz
- Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway; NORMENT and K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo, 0424 Oslo, Norway
| | - Mary Clarke
- Dublin and East Treatment and Early Care Team (DETECT) Services, Dublin, Ireland; College of Life Sciences, University College Dublin, Dublin, Ireland
| | - Lynn Mørch-Johnsen
- Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway; NORMENT and K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo, 0424 Oslo, Norway
| | - Ann Faerden
- NORMENT and K.G. Jebsen Centre for Psychosis Research, Institute of Clinical Medicine, University of Oslo, 0424 Oslo, Norway; Division of Mental Health and Addiction, Oslo University Hospital, Oslo, Norway
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23
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Steinau S, Stegmayer K, Lang FU, Jäger M, Strik W, Walther S. Comparison of psychopathological dimensions between major depressive disorder and schizophrenia spectrum disorders focusing on language, affectivity and motor behavior. Psychiatry Res 2017; 250:169-176. [PMID: 28167432 DOI: 10.1016/j.psychres.2017.01.084] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 12/25/2016] [Accepted: 01/29/2017] [Indexed: 10/20/2022]
Abstract
This study tested whether patients with major depressive disorder (MDD) and schizophrenia spectrum disorders would differ in three dimensions of psychopathology (language, affectivity and motor behavior) as assessed by the Bern Psychopathology Scale (BPS) in a cohort of 58 patients with MDD and 146 patients with schizophrenia spectrum disorders. The overall estimation of severity of each of the three dimensions was rated on a seven-point Likert scale from severely inhibited to severely disinhibited. Here, more than half of the patients endorsed ratings that showed normal or mildly (dis-)inhibited behavior. At group level more pronounced negative ratings of affect were seen in MDD. Group comparisons of the severity ratings on language or motor behavior yielded no differences between schizophrenia spectrum disorders and MDD. At the individuals' levels, extreme ratings in the language and motor dimensions were more frequent in schizophrenia spectrum disorders and in the affectivity dimension more frequent in MDD. Shared psychopathological features could be seen across diagnoses, supporting a dimensional approach to psychopathology in endogenous psychoses. However, the groups differ in the severity of affect ratings as well as in the distribution of language, affectivity and motor ratings with more variance among the group of schizophrenia spectrum disorders.
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Affiliation(s)
- Sarah Steinau
- University Hospital of Psychiatry, University of Bern, Bolligenstrasse 111, 3000 Bern 60, Switzerland
| | - Katharina Stegmayer
- University Hospital of Psychiatry, University of Bern, Bolligenstrasse 111, 3000 Bern 60, Switzerland
| | - Fabian U Lang
- Department of Psychiatry and Psychotherapy II, Ulm University, Günzburg, Germany
| | - Markus Jäger
- Department of Psychiatry and Psychotherapy II, Ulm University, Günzburg, Germany
| | - Werner Strik
- University Hospital of Psychiatry, University of Bern, Bolligenstrasse 111, 3000 Bern 60, Switzerland
| | - Sebastian Walther
- University Hospital of Psychiatry, University of Bern, Bolligenstrasse 111, 3000 Bern 60, Switzerland.
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24
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Viher PV, Stegmayer K, Giezendanner S, Federspiel A, Bohlhalter S, Vanbellingen T, Wiest R, Strik W, Walther S. Cerebral white matter structure is associated with DSM-5 schizophrenia symptom dimensions. NEUROIMAGE-CLINICAL 2016; 12:93-99. [PMID: 27408794 PMCID: PMC4925890 DOI: 10.1016/j.nicl.2016.06.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 06/09/2016] [Accepted: 06/15/2016] [Indexed: 12/21/2022]
Abstract
Diffusion tensor imaging (DTI) studies have provided evidence of widespread white matter (WM) abnormalities in schizophrenia. Although these abnormalities appear clinically significant, the relationship to specific clinical symptoms is limited and heterogeneous. This study examined the association between WM microstructure and the severity of the five main DSM-5 schizophrenia symptom dimensions. DTI was measured in forty patients with schizophrenia spectrum disorders. Using Tract-Based Spatial Statistics controlling for age, gender and antipsychotic dosage, our analyses revealed significant negative relationships between WM microstructure and two DSM-5 symptom dimensions: Whereas abnormal psychomotor behavior was particularly related to WM of motor tracts, negative symptoms were associated with WM microstructure of the prefrontal and right temporal lobes. However, we found no associations between WM microstructure and delusions, hallucinations or disorganized speech. These data highlight the relevance of characteristic WM disconnectivity patterns as markers for negative symptoms and abnormal psychomotor behavior in schizophrenia and provide evidence for relevant associations between brain structure and aberrant behavior. DTI study of brain-behavior associations of the new DSM-5 schizophrenia dimensions. The severity of the DSM-5 abnormal psychomotor behavior dimension is related to white matter microstructure in motor tracts. Associations of the DSM-5 negative symptom dimension with white matter microstructure are found in prefrontal and temporal clusters. Characteristic patterns of white matter microstructure argue for relevant associations between brain structure and aberrant behavior in schizophrenia.
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Affiliation(s)
- Petra V Viher
- Translational Research Center, University Hospital of Psychiatry, Bern, Switzerland
| | - Katharina Stegmayer
- Translational Research Center, University Hospital of Psychiatry, Bern, Switzerland
| | | | - Andrea Federspiel
- Translational Research Center, University Hospital of Psychiatry, Bern, Switzerland
| | - Stephan Bohlhalter
- Department of Clinical Research, Inselspital, Bern, Switzerland; Neurology and Neurorehabilitation Center, Luzerner Kantonsspital, Luzern, Switzerland
| | - Tim Vanbellingen
- Department of Clinical Research, Inselspital, Bern, Switzerland; Neurology and Neurorehabilitation Center, Luzerner Kantonsspital, Luzern, Switzerland
| | - Roland Wiest
- Support Center of Advanced Neuroimaging (SCAN), University Institute of Diagnostic and Interventional Neuroradiology, Inselspital, Bern, Switzerland
| | - Werner Strik
- Translational Research Center, University Hospital of Psychiatry, Bern, Switzerland
| | - Sebastian Walther
- Translational Research Center, University Hospital of Psychiatry, Bern, Switzerland
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25
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Hirjak D, Thomann PA, Kubera KM, Wolf ND, Sambataro F, Wolf RC. Motor dysfunction within the schizophrenia-spectrum: A dimensional step towards an underappreciated domain. Schizophr Res 2015; 169:217-233. [PMID: 26547881 DOI: 10.1016/j.schres.2015.10.022] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 10/09/2015] [Accepted: 10/15/2015] [Indexed: 12/14/2022]
Abstract
At the beginning of the 20th century, genuine motor abnormalities (GMA) were considered to be intricately linked to schizophrenia. Subsequently, however, GMA have been increasingly regarded as unspecific transdiagnostic phenomena or related to side effects of antipsychotic treatment. Despite possible medication confounds, within the schizophrenia spectrum GMA have been categorized into three broad categories, i.e. neurological soft signs, abnormal involuntary movements and catatonia. Schizophrenia patients show a substantial overlap across a broad range of distinct motor signs and symptoms suggesting a prominent involvement of the motor system in disease pathophysiology. There have been several attempts to increase reliability and validity in diagnosing schizophrenia based on behavior and neurobiology, yet relatively little attention has been paid to the motor domain in the past. Nevertheless, accumulating neuroscientific evidence suggests the possibility of a motor endophenotype in schizophrenia, and that GMA could represent a specific dimension within the schizophrenia-spectrum. Here, we review current neuroimaging research on GMA in schizophrenia with an emphasis on distinct and common mechanisms of brain dysfunction. Based on a dimensional approach we show that multimodal neuroimaging combined with fine-grained clinical examination can result in a comprehensive characterization of structural and functional brain changes that are presumed to underlie core GMA in schizophrenia. We discuss the possibility of a distinct motor domain, together with its implications for future research. Investigating GMA by means of multimodal neuroimaging can essentially contribute at identifying novel and biologically reliable phenotypes in psychiatry.
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Affiliation(s)
- Dusan Hirjak
- Center for Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Germany.
| | - Philipp A Thomann
- Center for Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Germany
| | - Katharina M Kubera
- Center for Psychosocial Medicine, Department of General Psychiatry, University of Heidelberg, Germany
| | - Nadine D Wolf
- Department of Psychiatry, Psychotherapy and Psychosomatics, Saarland University, Homburg, Germany
| | - Fabio Sambataro
- Department of Experimental and Clinical Medical Sciences (DISM), University of Udine, Udine, Italy
| | - Robert C Wolf
- Department of Psychiatry, Psychotherapy and Psychosomatics, Saarland University, Homburg, Germany
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26
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Walther S, Morrens M. Editorial: Psychomotor Symptomatology in Psychiatric Illnesses. Front Psychiatry 2015; 6:81. [PMID: 26082727 PMCID: PMC4450574 DOI: 10.3389/fpsyt.2015.00081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 05/17/2015] [Indexed: 12/19/2022] Open
Affiliation(s)
- Sebastian Walther
- University Hospital of Psychiatry, University of Bern , Bern , Switzerland
| | - Manuel Morrens
- Collaborative Antwerp Psychiatric Research Institute, University of Antwerp , Antwerp , Belgium
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