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Meyhoefer I, Sprenger A, Derad D, Grotegerd D, Leenings R, Leehr EJ, Breuer F, Surmann M, Rolfes K, Arolt V, Romer G, Lappe M, Rehder J, Koutsouleris N, Borgwardt S, Schultze-Lutter F, Meisenzahl E, Kircher TTJ, Keedy SS, Bishop JR, Ivleva EI, McDowell JE, Reilly JL, Hill SK, Pearlson GD, Tamminga CA, Keshavan MS, Gershon ES, Clementz BA, Sweeney JA, Hahn T, Dannlowski U, Lencer R. Evidence from comprehensive independent validation studies for smooth pursuit dysfunction as a sensorimotor biomarker for psychosis. Sci Rep 2024; 14:13859. [PMID: 38879556 PMCID: PMC11180169 DOI: 10.1038/s41598-024-64487-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Accepted: 06/10/2024] [Indexed: 06/19/2024] Open
Abstract
Smooth pursuit eye movements are considered a well-established and quantifiable biomarker of sensorimotor function in psychosis research. Identifying psychotic syndromes on an individual level based on neurobiological markers is limited by heterogeneity and requires comprehensive external validation to avoid overestimation of prediction models. Here, we studied quantifiable sensorimotor measures derived from smooth pursuit eye movements in a large sample of psychosis probands (N = 674) and healthy controls (N = 305) using multivariate pattern analysis. Balanced accuracies of 64% for the prediction of psychosis status are in line with recent results from other large heterogenous psychiatric samples. They are confirmed by external validation in independent large samples including probands with (1) psychosis (N = 727) versus healthy controls (N = 292), (2) psychotic (N = 49) and non-psychotic bipolar disorder (N = 36), and (3) non-psychotic affective disorders (N = 119) and psychosis (N = 51) yielding accuracies of 65%, 66% and 58%, respectively, albeit slightly different psychosis syndromes. Our findings make a significant contribution to the identification of biologically defined profiles of heterogeneous psychosis syndromes on an individual level underlining the impact of sensorimotor dysfunction in psychosis.
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Affiliation(s)
- Inga Meyhoefer
- Institute for Translational Psychiatry, University of Muenster, Albert Schweitzer Campus 1, Build. A9a, 48149, Muenster, Germany
- Otto-Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich-Heine University, Duesseldorf/LVR, Duesseldorf, Germany
| | - Andreas Sprenger
- Department of Neurology, University of Luebeck, Luebeck, Germany
| | - David Derad
- Department of Neurology, University of Luebeck, Luebeck, Germany
| | - Dominik Grotegerd
- Institute for Translational Psychiatry, University of Muenster, Albert Schweitzer Campus 1, Build. A9a, 48149, Muenster, Germany
| | - Ramona Leenings
- Institute for Translational Psychiatry, University of Muenster, Albert Schweitzer Campus 1, Build. A9a, 48149, Muenster, Germany
| | - Elisabeth J Leehr
- Institute for Translational Psychiatry, University of Muenster, Albert Schweitzer Campus 1, Build. A9a, 48149, Muenster, Germany
| | - Fabian Breuer
- Institute for Translational Psychiatry, University of Muenster, Albert Schweitzer Campus 1, Build. A9a, 48149, Muenster, Germany
| | - Marian Surmann
- Institute for Translational Psychiatry, University of Muenster, Albert Schweitzer Campus 1, Build. A9a, 48149, Muenster, Germany
| | - Karen Rolfes
- Institute for Translational Psychiatry, University of Muenster, Albert Schweitzer Campus 1, Build. A9a, 48149, Muenster, Germany
| | - Volker Arolt
- Institute for Translational Psychiatry, University of Muenster, Albert Schweitzer Campus 1, Build. A9a, 48149, Muenster, Germany
- Otto-Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany
| | - Georg Romer
- Department of Child Adolescence Psychiatry and Psychotherapy, University of Muenster, Muenster, Germany
| | - Markus Lappe
- Otto-Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany
- Institute of Psychology, University of Muenster, Muenster, Germany
| | - Johanna Rehder
- Institute of Psychology, University of Muenster, Muenster, Germany
| | - Nikolaos Koutsouleris
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilian University Munich, Munich, Germany
- Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
- Max-Planck-Institute of Psychiatry Munich, Munich, Germany
| | - Stefan Borgwardt
- Department of Psychiatry and Psychotherapy, University of Luebeck, Luebeck, Germany
- Department of Psychiatry, Psychiatric University Hospital, University of Basel, Basel, Switzerland
| | - Frauke Schultze-Lutter
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich-Heine University, Duesseldorf/LVR, Duesseldorf, Germany
- Department of Psychology, Faculty of Psychology, Airlangga University, Surabaya, Indonesia
- University Hospital of Child and Adolescent Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland
| | - Eva Meisenzahl
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich-Heine University, Duesseldorf/LVR, Duesseldorf, Germany
| | - Tilo T J Kircher
- Department of Psychiatry and Psychotherapy, Philipps-University Marburg, Marburg, Germany
| | - Sarah S Keedy
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, USA
| | - Jeffrey R Bishop
- Department of Experimental and Clinical Pharmacology and Department of Psychiatry and Behavioral Sciences, University of Minnesota, Minneapolis, USA
| | - Elena I Ivleva
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Jennifer E McDowell
- Departments of Psychology and Neuroscience, Bio-Imaging Research Center, University of Georgia, Athens, GA, USA
| | - James L Reilly
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Scot Kristian Hill
- Department of Psychology, Rosalind Franklin University of Medicine and Science, Chicago, IL, USA
| | - Godfrey D Pearlson
- Departments of Psychiatry and Neuroscience, Yale School of Medicine, and Olin Research Center, Institute of Living/Hartford Hospital, Hartford, CT, USA
| | - Carol A Tamminga
- Department of Psychiatry, The University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Matcheri S Keshavan
- Department of Psychiatry, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Elliot S Gershon
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, USA
| | - Brett A Clementz
- Departments of Psychology and Neuroscience, Bio-Imaging Research Center, University of Georgia, Athens, GA, USA
| | - John A Sweeney
- Huaxi MR Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, China
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, Cincinnati, USA
| | - Tim Hahn
- Institute for Translational Psychiatry, University of Muenster, Albert Schweitzer Campus 1, Build. A9a, 48149, Muenster, Germany
| | - Udo Dannlowski
- Institute for Translational Psychiatry, University of Muenster, Albert Schweitzer Campus 1, Build. A9a, 48149, Muenster, Germany
| | - Rebekka Lencer
- Institute for Translational Psychiatry, University of Muenster, Albert Schweitzer Campus 1, Build. A9a, 48149, Muenster, Germany.
- Otto-Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany.
- Department of Psychiatry and Psychotherapy, University of Luebeck, Luebeck, Germany.
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2
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Ekin M, Akdal G, Bora E. Antisaccade error rates in first-episode psychosis, ultra-high risk for psychosis and unaffected relatives of schizophrenia: A systematic review and meta-analysis. Schizophr Res 2024; 266:41-49. [PMID: 38367611 DOI: 10.1016/j.schres.2024.02.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 05/05/2023] [Accepted: 02/13/2024] [Indexed: 02/19/2024]
Abstract
BACKGROUND Antisaccade, which is described as looking at the opposite location of the target, is an eye movements paradigm used for assessing cognitive functions in schizophrenia. Initiation and sustainment of saccades in antisaccade are managed by frontal and parietal cortical areas. Antisaccade abnormalities are well-established findings in schizophrenia. However, studies in the early phases of psychotic disorders and clinical/familial risk for psychosis reported inconsistent findings. The current systematic review aimed to review the results of studies investigating antisaccade error rates in first-episode psychosis (FEP), individuals with ultra-high-risk for psychosis (UHRP), and familial-high-risk for psychosis (FHRP) compared to healthy controls. METHOD A meta-analysis of 17 studies was conducted to quantitatively review antisaccade errors in FEP, UHR-P and FHRP. The error rate (Hedges'g) was compared between the total of 860 FEP, UHRP, FHRP, and 817 healthy controls. Hedges' g for effect size, I2 for estimating the percentage of variability, and publication bias were evaluated through the R software. RESULTS The outcomes of this meta-analysis suggested that FEP is associated with a robust deficit in the antisaccade error rate (g = 1.16, CI = 0.95-1.38). Additionally, both the clinical and familial high-risk groups showed small but significant increases in AS errors (g = 0.26, CI = 0.02-0.52 and g = 0.34, CI = 0.13-0.55, respectively). CONCLUSION The large effect size estimated for FEP was compatible with previously reported results in chronic schizophrenia patients. Additionally, relatives had abnormalities with small to medium effect sizes and significant differences. The current findings suggest that antisaccade errors might be a potential endophenotype for psychotic disorders.
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Affiliation(s)
- Merve Ekin
- Department of Neurosciences, Institute of Health Sciences, Dokuz Eylül University, Izmir, Turkey; Institude of Psychology, SWPS University, Warsaw, Poland.
| | - Gülden Akdal
- Department of Neurosciences, Institute of Health Sciences, Dokuz Eylül University, Izmir, Turkey; Department of Neurology, Faculty of Medicine, Dokuz Eylül University, Izmir, Turkey.
| | - Emre Bora
- Department of Neurosciences, Institute of Health Sciences, Dokuz Eylül University, Izmir, Turkey; Department of Psychiatry, Faculty of Medicine, Dokuz Eylül University, Izmir, Turkey; Melbourne Neuropsychiatry Centre, Department of Psychiatry, University of Melbourne, Victoria, Australia.
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Tang B, Zhang W, Liu J, Deng S, Hu N, Li S, Zhao Y, Liu N, Zeng J, Cao H, Sweeney JA, Gong Q, Gu S, Lui S. Altered controllability of white matter networks and related brain function changes in first-episode drug-naive schizophrenia. Cereb Cortex 2023; 33:1527-1535. [PMID: 36790361 DOI: 10.1093/cercor/bhac421] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 09/25/2022] [Accepted: 09/26/2022] [Indexed: 11/06/2022] Open
Abstract
Understanding how structural connectivity alterations affect aberrant dynamic function using network control theory will provide new mechanistic insights into the pathophysiology of schizophrenia. The study included 140 drug-naive schizophrenia patients and 119 healthy controls (HCs). The average controllability (AC) quantifying capacity of brain regions/networks to shift the system into easy-to-reach states was calculated based on white matter connectivity and was compared between patients and HCs as well as functional network topological and dynamic properties. The correlation analysis between AC and duration of untreated psychosis (DUP) were conducted to characterize the controllability progression pattern without treatment effects. Relative to HCs, patients exhibited reduced AC in multiple nodes, mainly distributed in default mode network (DMN), visual network (VN), and subcortical regions, and increased AC in somatomotor network. These networks also had impaired functional topology and increased temporal variability in dynamic functional connectivity analysis. Longer DUP was related to greater reductions of AC in VN and DMN. The current study highlighted potential structural substrates underlying altered functional dynamics in schizophrenia, providing a novel understanding of the relationship of anatomic and functional network alterations.
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Affiliation(s)
- Biqiu Tang
- Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, Department of Radiology, West China Hospital of Sichuan University, No. 37 Guoxue Xiang, Chengdu 610041, China.,Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, No. 37 Guoxue Xiang, Chengdu 610041, China
| | - Wenjing Zhang
- Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, Department of Radiology, West China Hospital of Sichuan University, No. 37 Guoxue Xiang, Chengdu 610041, China.,Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, No. 37 Guoxue Xiang, Chengdu 610041, China
| | - Jiang Liu
- School of Computer Science and Engineering, University of Electronic Science and Technology of China, No. 2006 Xiyuan Avenue, Chengdu 611731, China
| | - Shikuang Deng
- School of Computer Science and Engineering, University of Electronic Science and Technology of China, No. 2006 Xiyuan Avenue, Chengdu 611731, China
| | - Na Hu
- Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, Department of Radiology, West China Hospital of Sichuan University, No. 37 Guoxue Xiang, Chengdu 610041, China.,Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, No. 37 Guoxue Xiang, Chengdu 610041, China
| | - Siyi Li
- Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, Department of Radiology, West China Hospital of Sichuan University, No. 37 Guoxue Xiang, Chengdu 610041, China.,Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, No. 37 Guoxue Xiang, Chengdu 610041, China
| | - Youjin Zhao
- Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, Department of Radiology, West China Hospital of Sichuan University, No. 37 Guoxue Xiang, Chengdu 610041, China.,Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, No. 37 Guoxue Xiang, Chengdu 610041, China
| | - Nian Liu
- Department of Radiology, Affiliated Hospital of North Sichuan Medical College, No 1 Maoyuan South Road, Shunqing District, Nanchong 637000, China
| | - Jiaxin Zeng
- Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, Department of Radiology, West China Hospital of Sichuan University, No. 37 Guoxue Xiang, Chengdu 610041, China.,Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, No. 37 Guoxue Xiang, Chengdu 610041, China
| | - Hengyi Cao
- Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, Department of Radiology, West China Hospital of Sichuan University, No. 37 Guoxue Xiang, Chengdu 610041, China.,Center for Psychiatric Neuroscience, Feinstein Institute for Medical Research, 350 Community Drive, Manhasset, NY 11030, United States.,Division of Psychiatry Research, Zucker Hillside Hospital, 75-59 263rd Street, Glen Oaks, NY 11004, United States
| | - John A Sweeney
- Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, Department of Radiology, West China Hospital of Sichuan University, No. 37 Guoxue Xiang, Chengdu 610041, China.,Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati College of Medicine, 260 Stetson Street, Cincinnati, OH 45219, United States
| | - Qiyong Gong
- Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, Department of Radiology, West China Hospital of Sichuan University, No. 37 Guoxue Xiang, Chengdu 610041, China.,Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, No. 37 Guoxue Xiang, Chengdu 610041, China
| | - Shi Gu
- School of Computer Science and Engineering, University of Electronic Science and Technology of China, No. 2006 Xiyuan Avenue, Chengdu 611731, China
| | - Su Lui
- Huaxi MR Research Center (HMRRC), Functional and Molecular Imaging Key Laboratory of Sichuan Province, Department of Radiology, West China Hospital of Sichuan University, No. 37 Guoxue Xiang, Chengdu 610041, China.,Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, No. 37 Guoxue Xiang, Chengdu 610041, China
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4
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Hills PJ, Vasilev MR, Ford P, Snell L, Whitworth E, Parsons T, Morisson R, Silveira A, Angele B. Sensory gating is related to positive and disorganised schizotypy in contrast to smooth pursuit eye movements and latent inhibition. Neuropsychologia 2021; 161:107989. [PMID: 34419489 DOI: 10.1016/j.neuropsychologia.2021.107989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 07/30/2021] [Accepted: 08/05/2021] [Indexed: 10/20/2022]
Abstract
Since the characteristics and symptoms of both schizophrenia and schizotypy are manifested heterogeneously, it is possible that different endophenotypes and neurophysiological measures (sensory gating and smooth pursuit eye movement errors) represent different clusters of symptoms. Participants (N = 205) underwent a standard conditioned-pairing paradigm to establish their sensory gating ratio, a smooth-pursuit eye-movement task, a latent inhibition task, and completed the Schizotypal Personality Questionnaire. A Multidimensional Scaling analysis revealed that sensory gating was related to positive and disorganised dimensions of schizotypy. Latent inhibition and prepulse inhibition were not related to any dimension of schizotypy. Smooth pursuit eye movement error was unrelated to sensory gating and latent inhibition, but was related to negative dimensions of schizotypy. Our findings suggest that the symptom clusters associated with two main endophenotypes are largely independent. To fully understand symptomology and outcomes of schizotypal traits, the different subtypes of schizotypy (and potentially, schizophrenia) ought to be considered separately rather than together.
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5
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Athanasopoulos F, Saprikis OV, Margeli M, Klein C, Smyrnis N. Towards Clinically Relevant Oculomotor Biomarkers in Early Schizophrenia. Front Behav Neurosci 2021; 15:688683. [PMID: 34177483 PMCID: PMC8222521 DOI: 10.3389/fnbeh.2021.688683] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 05/11/2021] [Indexed: 12/30/2022] Open
Abstract
In recent years, psychiatric research has focused on the evaluation and implementation of biomarkers in the clinical praxis. Oculomotor function deviances are among the most consistent and replicable cognitive deficits in schizophrenia and have been suggested as viable candidates for biomarkers. In this narrative review, we focus on oculomotor function in first-episode psychosis, recent onset schizophrenia as well as individuals at high risk for developing psychosis. We critically discuss the evidence for the possible utilization of oculomotor function measures as diagnostic, susceptibility, predictive, monitoring, and prognostic biomarkers for these conditions. Based on the current state of research we conclude that there are not sufficient data to unequivocally support the use of oculomotor function measures as biomarkers in schizophrenia.
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Affiliation(s)
- Fotios Athanasopoulos
- 2nd Department of Psychiatry, School of Medicine, National and Kapodistrian University of Athens, University General Hospital "ATTIKON", Athens, Greece.,Laboratory of Cognitive Neuroscience and Sensorimotor Control, University Mental Health, Neurosciences and Precision Medicine Research Institute "COSTAS STEFANIS", Athens, Greece
| | - Orionas-Vasilis Saprikis
- 2nd Department of Psychiatry, School of Medicine, National and Kapodistrian University of Athens, University General Hospital "ATTIKON", Athens, Greece.,Laboratory of Cognitive Neuroscience and Sensorimotor Control, University Mental Health, Neurosciences and Precision Medicine Research Institute "COSTAS STEFANIS", Athens, Greece
| | - Myrto Margeli
- 2nd Department of Psychiatry, School of Medicine, National and Kapodistrian University of Athens, University General Hospital "ATTIKON", Athens, Greece.,Laboratory of Cognitive Neuroscience and Sensorimotor Control, University Mental Health, Neurosciences and Precision Medicine Research Institute "COSTAS STEFANIS", Athens, Greece
| | - Christoph Klein
- 2nd Department of Psychiatry, School of Medicine, National and Kapodistrian University of Athens, University General Hospital "ATTIKON", Athens, Greece.,Department of Child and Adolescent Psychiatry, Medical Faculty, University of Freiburg, Freiburg, Germany.,Department of Child and Adolescent Psychiatry, Medical Faculty, University of Cologne, Cologne, Germany
| | - Nikolaos Smyrnis
- 2nd Department of Psychiatry, School of Medicine, National and Kapodistrian University of Athens, University General Hospital "ATTIKON", Athens, Greece.,Laboratory of Cognitive Neuroscience and Sensorimotor Control, University Mental Health, Neurosciences and Precision Medicine Research Institute "COSTAS STEFANIS", Athens, Greece
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6
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Shafer RL, Lewis MH, Newell KM, Bodfish JW. Atypical neural processing during the execution of complex sensorimotor behavior in autism. Behav Brain Res 2021; 409:113337. [PMID: 33933522 PMCID: PMC8188828 DOI: 10.1016/j.bbr.2021.113337] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 04/02/2021] [Accepted: 04/27/2021] [Indexed: 11/17/2022]
Abstract
Stereotyped behavior is rhythmic, repetitive movement that is essentially invariant in form. Stereotypy is common in several clinical disorders, such as autism spectrum disorders (ASD), where it is considered maladaptive. However, it also occurs early in typical development (TD) where it is hypothesized to serve as the foundation on which complex, adaptive motor behavior develops. This transition from stereotyped to complex movement in TD is thought to be supported by sensorimotor integration. Stereotypy in clinical disorders may persist due to deficits in sensorimotor integration. The present study assessed whether differences in sensorimotor processing may limit the expression of complex motor behavior in individuals with ASD and contribute to the clinical stereotypy observed in this population. Adult participants with ASD and TD performed a computer-based stimulus-tracking task in the presence and absence of visual feedback. Electroencephalography was recorded during the task. Groups were compared on motor performance (root mean square error), motor complexity (sample entropy), and neural complexity (multiscale sample entropy of the electroencephalography signal) in the presence and absence of visual feedback. No group differences were found for motor performance or motor complexity. The ASD group demonstrated greater neural complexity and greater differences between feedback conditions than TD individuals, specifically in signals relevant to sensorimotor processing. Motor performance and motor complexity correlated with clinical stereotypy in the ASD group. These findings support the hypothesis that individuals with ASD have differences in sensorimotor processing when executing complex motor behavior and that stereotypy is associated with low motor complexity.
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Affiliation(s)
- Robin L Shafer
- Vanderbilt Brain Institute, Vanderbilt University, 6133 Medical Research Building III, 465 21(st) Avenue South, Nashville, TN, 37232, USA.
| | - Mark H Lewis
- Department of Psychiatry, University of Florida College of Medicine, PO Box 100256, L4-100 McKnight Brain Institute, 1149 Newell Drive, Gainesville, FL, 3261, USA.
| | - Karl M Newell
- Department of Kinesiology, University of Georgia, G3 Aderhold Hall, 110 Carlton Street, Athens, GA, 30602, USA.
| | - James W Bodfish
- Vanderbilt Brain Institute, Vanderbilt University, 6133 Medical Research Building III, 465 21(st) Avenue South, Nashville, TN, 37232, USA; Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, 8310 Medical Center East, 1215 21(st) Avenue South, Nashville, TN, 37232, USA.
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7
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McKinney RA, Avery SN, Armstrong K, Blackford JU, Woodward ND, Heckers S. Relational memory in the early stage of psychotic bipolar disorder. Psychiatry Res 2020; 294:113508. [PMID: 33096436 PMCID: PMC7809627 DOI: 10.1016/j.psychres.2020.113508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 10/08/2020] [Indexed: 11/26/2022]
Abstract
Relational memory is impaired in psychotic disorders. In non-affective psychotic disorders, relational memory deficits are present in the early stage of illness and become more pronounced in the chronic stage. Previous studies have demonstrated cognitive deficits in early-stage psychotic bipolar disorder, but it is unclear whether relational memory is impaired. We examined relational memory using a face-scene binding task in early-stage psychotic bipolar disorder patients (n = 33) and compared their performance with healthy control (n = 40) and early-stage non-affective psychosis participants (n = 40). During training, participants learned to associate faces with background scenes. During testing, participants viewed a scene overlaid by three faces and were asked to recall the matching face. Relational memory was assessed indirectly using eye movements and explicitly using forced-choice recognition. Preferential viewing of the matching face, as captured by overall proportion of viewing and viewing across time, was significantly lower in psychotic bipolar disorder than in the healthy control group. However, preferential viewing of the matching face in psychotic bipolar disorder was significantly better than in non-affective psychosis. These findings provide novel evidence that relational memory in patients with early-stage psychotic bipolar disorder is intermediate between healthy control and early-stage non-affective psychosis subjects.
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Affiliation(s)
- Rachel A McKinney
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN 37212 USA
| | - Suzanne N Avery
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN 37212 USA.
| | - Kristan Armstrong
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN 37212 USA
| | - Jennifer Urbano Blackford
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN 37212 USA; Research Health Scientist, Research and Development, Department of Veterans Affairs Medical Center, Nashville, TN 37212 USA
| | - Neil D Woodward
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN 37212 USA
| | - Stephan Heckers
- Department of Psychiatry and Behavioral Sciences, Vanderbilt University Medical Center, Nashville, TN 37212 USA
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8
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Hudgens-Haney ME, Clementz BA, Ivleva EI, Keshavan MS, Pearlson GD, Gershon ES, Keedy SK, Sweeney JA, Gaudoux F, Bunouf P, Canolle B, Tonner F, Gatti-McArthur S, Tamminga CA. Cognitive Impairment and Diminished Neural Responses Constitute a Biomarker Signature of Negative Symptoms in Psychosis. Schizophr Bull 2020; 46:1269-1281. [PMID: 32043133 PMCID: PMC7505197 DOI: 10.1093/schbul/sbaa001] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The treatment of negative symptoms (NS) in psychosis represents an urgent unmet medical need given the significant functional impairment it contributes to psychosis syndromes. The lack of progress in treating NS is impacted by the lack of known pathophysiology or associated quantitative biomarkers, which could provide tools for research. This current analysis investigated potential associations between NS and an extensive battery of behavioral and brain-based biomarkers in 932 psychosis probands from the B-SNIP database. The current analyses examined associations between PANSS-defined NS and (1) cognition, (2) pro-/anti-saccades, (3) evoked and resting-state electroencephalography (EEG), (4) resting-state fMRI, and (5) tractography. Canonical correlation analyses yielded symptom-biomarker constructs separately for each biomarker modality. Biomarker modalities were integrated using canonical discriminant analysis to summarize the symptom-biomarker relationships into a "biomarker signature" for NS. Finally, distinct biomarker profiles for 2 NS domains ("diminished expression" vs "avolition/apathy") were computed using step-wise linear regression. NS were associated with cognitive impairment, diminished EEG response amplitudes, deviant resting-state activity, and oculomotor abnormalities. While a connection between NS and poor cognition has been established, association to neurophysiology is novel, suggesting directions for future mechanistic studies. Each biomarker modality was related to NS in distinct and complex ways, giving NS a rich, interconnected fingerprint and suggesting that any one biomarker modality may not adequately capture the full spectrum of symptomology.
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Affiliation(s)
| | - Brett A Clementz
- Departments of Psychology and Neuroscience, Bio-Imaging Research Center, University of Georgia, Athens, GA
| | - Elena I Ivleva
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX
| | - Matcheri S Keshavan
- Department of Psychiatry, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - Godfrey D Pearlson
- Departments of Psychiatry and Neurobiology, Yale University School of Medicine, New Haven, CT
- Institute of Living, Hartford Hospital, Hartford, CT
| | | | - Sarah K Keedy
- Department of Psychiatry, University of Chicago, Chicago, IL
| | - John A Sweeney
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH
| | | | | | | | | | | | - Carol A Tamminga
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX
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9
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Brakemeier S, Sprenger A, Meyhöfer I, McDowell JE, Rubin LH, Hill SK, Keshavan MS, Pearlson GD, Tamminga CA, Gershon ES, Keedy SS, Sweeney JA, Clementz BA, Lencer R. Smooth pursuit eye movement deficits as a biomarker for psychotic features in bipolar disorder-Findings from the PARDIP study. Bipolar Disord 2020; 22:602-611. [PMID: 31721386 DOI: 10.1111/bdi.12865] [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] [Indexed: 12/01/2022]
Abstract
OBJECTIVES Smooth pursuit eye movement deficits are an established psychosis biomarker across schizophrenia, schizoaffective and psychotic bipolar disorder (BPwP). Whether smooth pursuit deficits are also seen in bipolar disorder without psychosis (BPwoP) is unclear. Here we present data from the Psychosis and Affective Research Domains and Intermediate Phenotypes (PARDIP) study comparing bipolar patients with and without psychotic features. METHODS Probands with BPwP (N = 49) and BPwoP (N = 36), and healthy controls (HC, N = 71) performed eye tracking tasks designed to evaluate specific sensorimotor components relevant for pursuit initiation and pursuit maintenance. RESULTS While BPwoP did not differ from either BPwP or HC on initial eye acceleration, they performed significantly better than BPwP on early (P < .01) and predictive (P = .02) pursuit maintenance measures, both without differing from HC. BPwP were impaired compared to HC on initial eye acceleration, and on early and predictive pursuit maintenance (all P < .01). In contrast to the three pursuit measures, BPwP and BPwoP were both impaired on general neurocognitive assessments in relation to HC (both P < .001), without a significant difference between the two bipolar patient groups. CONCLUSIONS Our findings support the model that impairments of sensorimotor and cognitive processing as required for early and later predictive smooth pursuit maintenance are relatively specific to those bipolar patients with a history of psychosis. This suggests that the neural circuitry for developing feed-forward predictive models for accurate pursuit maintenance is associated with the occurrence of psychotic features in bipolar patients. In contrast, generalized neuropsychological impairments did not differentiate the two bipolar patient groups.
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Affiliation(s)
- Svenja Brakemeier
- Department of Psychiatry and Psychotherapy, University of Muenster, Muenster, Germany
| | - Andreas Sprenger
- Department of Neurology, University of Luebeck, Luebeck, Germany
| | - Inga Meyhöfer
- Department of Psychiatry and Psychotherapy, University of Muenster, Muenster, Germany.,Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany
| | - Jennifer E McDowell
- Departments of Psychology and Neuroscience, Bio-Imaging Research Center, University of Georgia, Athens, GA, USA
| | - Leah H Rubin
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - S Kristian Hill
- Department of Psychology, Rosalind Franklin University of Medicine and Science, Chicago, IL, USA
| | - Matcheri S Keshavan
- Department of Psychiatry, Harvard Medical School, Beth Israel Deacones Medical Center, Boston, MA, USA
| | - Godfrey D Pearlson
- Departments of Psychiatry and Neuroscience, Yale School of Medicine, and Olin Research Center, Institute of Living/Hartford Hospital, Hartford, CT, USA
| | - Carol A Tamminga
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Elliot S Gershon
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA
| | - Sarah S Keedy
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA
| | - John A Sweeney
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, USA
| | - Brett A Clementz
- Departments of Psychology and Neuroscience, Bio-Imaging Research Center, University of Georgia, Athens, GA, USA
| | - Rebekka Lencer
- Department of Psychiatry and Psychotherapy, University of Muenster, Muenster, Germany.,Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany
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10
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Shafer RL, Solomon EM, Newell KM, Lewis MH, Bodfish JW. Visual feedback during motor performance is associated with increased complexity and adaptability of motor and neural output. Behav Brain Res 2019; 376:112214. [PMID: 31494179 DOI: 10.1016/j.bbr.2019.112214] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/30/2019] [Accepted: 09/04/2019] [Indexed: 11/19/2022]
Abstract
Complex motor behavior is believed to be dependent on sensorimotor integration - the neural process of using sensory input to plan, guide, and correct movements. Previous studies have shown that the complexity of motor output is low when sensory feedback is withheld during precision motor tasks. However, much of this research has focused on motor behavior rather than neural processing, and therefore, has not specifically assessed the role of sensorimotor neural functioning in the execution of complex motor behavior. The present study uses a stimulus-tracking task with simultaneous electroencephalography (EEG) recording to assess the effect of visual feedback on motor performance, motor complexity, and sensorimotor neural processing in healthy adults. The complexity of the EEG signal was analyzed to capture the information content in frequency bands (alpha and beta) and scalp regions (central, parietal, and occipital) that are associated with sensorimotor processing. Consistent with previous literature, motor performance and its complexity were higher when visual feedback was provided relative to when it was withheld. The complexity of the neural signal was also higher when visual feedback was provided. This was most robust at frequency bands (alpha and beta) and scalp regions (parietal and occipital) associated with sensorimotor processing. The findings show that visual feedback increases the information available to the brain when generating complex, adaptive motor output.
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Affiliation(s)
- Robin L Shafer
- Vanderbilt Brain Institute, Vanderbilt University, 6133 Medical Research Building III, 465 21st Avenue South, Nashville, TN, 37232, USA.
| | - Eli M Solomon
- Neuroscience and Behavior Program, Wesleyan University Rm 257 Hall-Atwater, Wesleyan University, Middletown, CT, 06459, USA.
| | - Karl M Newell
- Department of Kinesiology, University of Georgia, G3 Aderhold Hall, 110 Carlton Street, Athens, GA, 30602, USA.
| | - Mark H Lewis
- Department of Psychiatry, University of Florida College of Medicine, PO Box 100256, L4-100 McKnight Brain Institute, 1149 Newell Drive, Gainesville, FL, 32611, USA.
| | - James W Bodfish
- Vanderbilt Brain Institute, Vanderbilt University, 6133 Medical Research Building III, 465 21st Avenue South, Nashville, TN, 37232, USA; Department of Hearing and Speech Sciences, Vanderbilt University Medical Center, 8310 Medical Center East, 1215 21st Avenue South, Nashville, TN, 37232, USA.
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11
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Silberg JE, Agtzidis I, Startsev M, Fasshauer T, Silling K, Sprenger A, Dorr M, Lencer R. Free visual exploration of natural movies in schizophrenia. Eur Arch Psychiatry Clin Neurosci 2019; 269:407-418. [PMID: 29305645 DOI: 10.1007/s00406-017-0863-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 12/28/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND Eye tracking dysfunction (ETD) observed with standard pursuit stimuli represents a well-established biomarker for schizophrenia. How ETD may manifest during free visual exploration of real-life movies is unclear. METHODS Eye movements were recorded (EyeLink®1000) while 26 schizophrenia patients and 25 healthy age-matched controls freely explored nine uncut movies and nine pictures of real-life situations for 20 s each. Subsequently, participants were shown still shots of these scenes to decide whether they had explored them as movies or pictures. Participants were additionally assessed on standard eye-tracking tasks. RESULTS Patients made smaller saccades (movies (p = 0.003), pictures (p = 0.002)) and had a stronger central bias (movies and pictures (p < 0.001)) than controls. In movies, patients' exploration behavior was less driven by image-defined, bottom-up stimulus saliency than controls (p < 0.05). Proportions of pursuit tracking on movies differed between groups depending on the individual movie (group*movie p = 0.011, movie p < 0.001). Eye velocity on standard pursuit stimuli was reduced in patients (p = 0.029) but did not correlate with pursuit behavior on movies. Additionally, patients obtained lower rates of correctly identified still shots as movies or pictures (p = 0.046). CONCLUSION Our results suggest a restricted centrally focused visual exploration behavior in patients not only on pictures, but also on movies of real-life scenes. While ETD observed in the laboratory cannot be directly transferred to natural viewing conditions, these alterations support a model of impairments in motion information processing in patients resulting in a reduced ability to perceive moving objects and less saliency driven exploration behavior presumably contributing to alterations in the perception of the natural environment.
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Affiliation(s)
- Johanna Elisa Silberg
- Department of Psychiatry and Psychotherapy, University of Muenster, Albert-Schweitzer-Campus 1, Geb. A9, 48149, Muenster, Germany
| | - Ioannis Agtzidis
- Chair of Human-Machine Communication, Technical University Munich, Munich, Germany
| | - Mikhail Startsev
- Chair of Human-Machine Communication, Technical University Munich, Munich, Germany
| | - Teresa Fasshauer
- Department of Psychiatry and Psychotherapy, University of Muenster, Albert-Schweitzer-Campus 1, Geb. A9, 48149, Muenster, Germany
| | - Karen Silling
- Department of Psychiatry and Psychotherapy, University of Muenster, Albert-Schweitzer-Campus 1, Geb. A9, 48149, Muenster, Germany
| | - Andreas Sprenger
- Department of Neurology and Institute of Psychology II, University of Luebeck, Lübeck, Germany
| | - Michael Dorr
- Chair of Human-Machine Communication, Technical University Munich, Munich, Germany
| | - Rebekka Lencer
- Department of Psychiatry and Psychotherapy, University of Muenster, Albert-Schweitzer-Campus 1, Geb. A9, 48149, Muenster, Germany. .,Otto-Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany.
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12
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Bey K, Meyhöfer I, Lennertz L, Grützmann R, Heinzel S, Kaufmann C, Klawohn J, Riesel A, Ettinger U, Kathmann N, Wagner M. Schizotypy and smooth pursuit eye movements as potential endophenotypes of obsessive-compulsive disorder. Eur Arch Psychiatry Clin Neurosci 2019; 269:235-243. [PMID: 29721727 DOI: 10.1007/s00406-018-0899-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 04/24/2018] [Indexed: 12/27/2022]
Abstract
Patients with obsessive-compulsive disorder (OCD) show dysfunctions of the fronto-striatal circuitry, which imply corresponding oculomotor deficits including smooth pursuit eye movements (SPEM). However, evidence for a deficit in SPEM is inconclusive, with some studies reporting reduced velocity gain while others did not find any SPEM dysfunctions in OCD patients. Interestingly, psychosis-like traits have repeatedly been linked to both OCD and impaired SPEM. Here, we examined a large sample of n = 168 patients with OCD, n = 93 unaffected first-degree relatives and n = 171 healthy control subjects to investigate whether elevated levels of schizotypy and SPEM deficits represent potential endophenotypes of OCD. We applied a SPEM task with high demands on predictive pursuit that is more sensitive to assess executive dysfunctions than a standard task with continuous visual feedback, as episodes of target blanking put increased demands on basal ganglia and prefrontal involvement. Additionally, we examined the relation between schizotypy and SPEM performance in OCD patients and their relatives. Results indicate that OCD patients and unaffected relatives do not show deficient performance in either standard or predictive SPEM. Yet, both patients and relatives exhibited elevated levels of schizotypy, and schizotypy was significantly correlated with velocity gain during standard trials in unmedicated and depression-free OCD patients. These findings highlight the role of schizotypy as a candidate endophenotype of OCD and add to the growing evidence for predisposing personality traits in OCD. Furthermore, intact gain may represent a key characteristic that distinguishes the OCD and schizophrenia patient populations.
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Affiliation(s)
- Katharina Bey
- Department of Psychiatry and Psychotherapy, University of Bonn, Sigmund-Freud-Str. 25, 53127, Bonn, Germany. .,German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.
| | - Inga Meyhöfer
- Department of Psychology, University of Bonn, Bonn, Germany.,Department of Psychiatry and Psychotherapy, University of Münster, Münster, Germany
| | - Leonhard Lennertz
- Department of Psychiatry and Psychotherapy, University of Bonn, Sigmund-Freud-Str. 25, 53127, Bonn, Germany
| | - Rosa Grützmann
- Department of Psychology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Stephan Heinzel
- Department of Psychology, Humboldt-Universität zu Berlin, Berlin, Germany.,Clinical Psychology and Psychotherapy, Freie Universität Berlin, Berlin, Germany
| | - Christian Kaufmann
- Department of Psychology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Julia Klawohn
- Department of Psychology, Humboldt-Universität zu Berlin, Berlin, Germany.,Biomedical Sciences and Psychology, Florida State University, Tallahassee, FL, USA
| | - Anja Riesel
- Department of Psychology, Humboldt-Universität zu Berlin, Berlin, Germany
| | | | - Norbert Kathmann
- Department of Psychology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Michael Wagner
- Department of Psychiatry and Psychotherapy, University of Bonn, Sigmund-Freud-Str. 25, 53127, Bonn, Germany.,German Center for Neurodegenerative Diseases (DZNE), Bonn, Germany.,Department for Neurodegenerative Diseases and Geriatric Psychiatry, University Hospital Bonn, Bonn, Germany
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13
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Lencer R, Mills LJ, Alliey-Rodriguez N, Shafee R, Lee AM, Reilly JL, Sprenger A, McDowell JE, McCarroll SA, Keshavan MS, Pearlson GD, Tamminga CA, Clementz BA, Gershon ES, Sweeney JA, Bishop JR. Genome-wide association studies of smooth pursuit and antisaccade eye movements in psychotic disorders: findings from the B-SNIP study. Transl Psychiatry 2017; 7:e1249. [PMID: 29064472 PMCID: PMC5682604 DOI: 10.1038/tp.2017.210] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Accepted: 07/14/2017] [Indexed: 02/07/2023] Open
Abstract
Eye movement deviations, particularly deficits of initial sensorimotor processing and sustained pursuit maintenance, and antisaccade inhibition errors, are established intermediate phenotypes for psychotic disorders. We here studied eye movement measures of 849 participants from the Bipolar-Schizophrenia Network on Intermediate Phenotypes (B-SNIP) study (schizophrenia N=230, schizoaffective disorder N=155, psychotic bipolar disorder N=206 and healthy controls N=258) as quantitative phenotypes in relation to genetic data, while controlling for genetically derived ancestry measures, age and sex. A mixed-modeling genome-wide association studies approach was used including ~4.4 million genotypes (PsychChip and 1000 Genomes imputation). Across participants, sensorimotor processing at pursuit initiation was significantly associated with a single nucleotide polymorphism in IPO8 (12p11.21, P=8 × 10-11), whereas suggestive associations with sustained pursuit maintenance were identified with SNPs in SH3GL2 (9p22.2, P=3 × 10-8). In participants of predominantly African ancestry, sensorimotor processing was also significantly associated with SNPs in PCDH12 (5q31.3, P=1.6 × 10-10), and suggestive associations were observed with NRSN1 (6p22.3, P=5.4 × 10-8) and LMO7 (13q22.2, P=7.3x10-8), whereas antisaccade error rate was significantly associated with a non-coding region at chromosome 7 (P=6.5 × 10-9). Exploratory pathway analyses revealed associations with nervous system development and function for 40 top genes with sensorimotor processing and pursuit maintenance (P=4.9 × 10-2-9.8 × 10-4). Our findings suggest novel patterns of genetic variation relevant for brain systems subserving eye movement control known to be impaired in psychotic disorders. They include genes involved in nuclear trafficking and gene silencing (IPO8), fast axonal guidance and synaptic specificity (PCDH12), transduction of nerve signals (NRSN1), retinal degeneration (LMO7), synaptic glutamate release (SH3GL2), and broader nervous system development and function.
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Affiliation(s)
- R Lencer
- Department of Psychiatry and Psychotherapy, Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster, Germany
| | - L J Mills
- Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, MN, USA
| | - N Alliey-Rodriguez
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA
| | - R Shafee
- Department of Genetics, Harvard Medical School, Boston, MA, USA
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - A M Lee
- Department of Experimental and Clinical Pharmacology, College of Pharmacy, University of Minnesota, Minneapolis, MN, USA
| | - J L Reilly
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - A Sprenger
- Department of Neurology, University of Luebeck, Luebeck, Germany
| | - J E McDowell
- Department of Psychology and Neuroscience, BioImaging Research Center, University of Georgia, Athens, GA, USA
| | - S A McCarroll
- Department of Genetics, Harvard Medical School, Boston, MA, USA
| | - M S Keshavan
- Department of Psychiatry, Harvard Medical School, Beth Israel Deacones Medical Center, Boston, MA, USA
| | - G D Pearlson
- Departments of Psychiatry and Neurobiology, Yale University School of Medicine, New Haven, CT, USA
- Institute of Living, Hartford Hospital, Hartford, CT, USA
| | - C A Tamminga
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - B A Clementz
- Department of Psychology and Neuroscience, BioImaging Research Center, University of Georgia, Athens, GA, USA
| | - E S Gershon
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, IL, USA
| | - J A Sweeney
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, OH, USA
| | - J R Bishop
- Department of Experimental and Clinical Pharmacology, College of Pharmacy, University of Minnesota, Minneapolis, MN, USA
- Department of Psychiatry, University of Minnesota College of Medicine, Minneapolis, MN, USA
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14
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Law PC, Gurvich CT, Ngo TT, Miller SM. Evidence that eye-movement profiles do not explain slow binocular rivalry rate in bipolar disorder: support for a perceptual endophenotype. Bipolar Disord 2017; 19:465-476. [PMID: 28714555 DOI: 10.1111/bdi.12515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Accepted: 05/31/2017] [Indexed: 01/12/2023]
Abstract
OBJECTIVES Presenting conflicting images simultaneously, one to each eye, produces perceptual alternations known as binocular rivalry (BR). Slow BR rate has been proposed as an endophenotype for bipolar disorder (BD) for use in large-scale genome-wide association studies. However, the trait could conceivably reflect eye movement (EM) dysfunction in BD rather than anomalous perceptual processing per se. To address this question, we examined the relationship between EM profiles and BR rate for various stimulus types in BD and healthy subjects. We also examined differences in EM profiles between these groups. METHODS Employing a repeated-measures within-subjects design, 20 BD outpatients and 20 age- and sex-matched healthy controls completed EM tasks and separate BR tasks involving a range of stimuli with different drift speeds. The association between each EM measure and BR rate was examined with correlational analyses for all stimulus conditions in both groups. Between-group comparisons were performed to determine any differences in those EM measures. Corresponding Bayesian analyses were also conducted. RESULTS There were no EM measures that showed a significant relationship with BR rate in either the BD group or the healthy group (P≥7.87×10-3 ), where those EM measures were also significantly different between the BD and healthy groups (P≥1.32 × 10-2 ). These findings were verified with Bayes factors. CONCLUSIONS The results provide evidence that EM profiles do not explain the slow BR endophenotype for BD, thus indicating that the trait reflects anomalous perceptual processing per se. This perceptual trait can be employed in clinical, genetic, mechanistic and pathophysiological studies.
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Affiliation(s)
- Phillip Cf Law
- Monash Alfred Psychiatry Research Centre, Monash University Central Clinical School and The Alfred Hospital, Melbourne, Australia
| | - Caroline T Gurvich
- Monash Alfred Psychiatry Research Centre, Monash University Central Clinical School and The Alfred Hospital, Melbourne, Australia
| | - Trung T Ngo
- Monash Alfred Psychiatry Research Centre, Monash University Central Clinical School and The Alfred Hospital, Melbourne, Australia.,Genetic Epidemiology Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Australia.,Mater Research Institute-UQ, Neurosciences & Cognitive Health Program, Faculty of Medicine, University of Queensland, Brisbane, Australia
| | - Steven M Miller
- Monash Alfred Psychiatry Research Centre, Monash University Central Clinical School and The Alfred Hospital, Melbourne, Australia.,School of Psychological Sciences, Monash University, Melbourne, Australia
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15
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Shafer RL, Newell KM, Lewis MH, Bodfish JW. A Cohesive Framework for Motor Stereotypy in Typical and Atypical Development: The Role of Sensorimotor Integration. Front Integr Neurosci 2017; 11:19. [PMID: 28890690 PMCID: PMC5575145 DOI: 10.3389/fnint.2017.00019] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 08/14/2017] [Indexed: 12/13/2022] Open
Abstract
Stereotyped motor behavior manifests as rhythmic, repetitive movements. It is common in several neurologic and psychiatric disorders where it is considered maladaptive. However, it also occurs early in typical development where it serves an adaptive function in the development of complex, controlled motor behavior. Currently, no framework accounts for both adaptive and maladaptive forms of motor stereotypy. We propose a conceptual model that implicates sensorimotor mechanisms in the phenomenology of adaptive and maladaptive stereotypy. The extensive structural and functional connectivity between sensory and motor neural circuits evidences the importance of sensory integration in the production of controlled movement. In support of our model, motor stereotypy in normative development occurs when the sensory and motor brain regions are immature and the infant has limited sensory and motor experience. With maturation and experience, complex movements develop and replace simple, stereotyped movements. This developmental increase in motor complexity depends on the availability of sensory feedback indicating that the integration of sensory information with ongoing movement allows individuals to adaptively cater their movements to the environmental context. In atypical development, altered neural function of sensorimotor circuitry may limit an individual's ability to integrate sensory feedback to adapt movements to appropriately respond to environmental conditions. Consequently, the motor repertoire would remain relatively simple, resulting in the persistence of motor stereotypy. A framework that considers motor stereotypy as a manifestation of low motor complexity resulting from poor sensorimotor integration has many implications for research, identification and treatment of motor stereotypy in a variety of developmental disorders.
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Affiliation(s)
- Robin L Shafer
- Vanderbilt Neuroscience Graduate Program, Vanderbilt Brain Institute, Vanderbilt UniversityNashville, TN, United States
| | - Karl M Newell
- Department of Kinesiology, University of GeorgiaAthens, GA, United States
| | - Mark H Lewis
- Department of Psychiatry, University of FloridaGainesville, FL, United States
| | - James W Bodfish
- Vanderbilt Neuroscience Graduate Program, Vanderbilt Brain Institute, Vanderbilt UniversityNashville, TN, United States.,Department of Hearing and Speech Sciences, Vanderbilt University Medical CenterNashville, TN, United States
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16
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Trillenberg P, Sprenger A, Talamo S, Herold K, Helmchen C, Verleger R, Lencer R. Visual and non-visual motion information processing during pursuit eye tracking in schizophrenia and bipolar disorder. Eur Arch Psychiatry Clin Neurosci 2017; 267:225-235. [PMID: 26816222 DOI: 10.1007/s00406-016-0671-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 01/11/2016] [Indexed: 11/29/2022]
Abstract
Despite many reports on visual processing deficits in psychotic disorders, studies are needed on the integration of visual and non-visual components of eye movement control to improve the understanding of sensorimotor information processing in these disorders. Non-visual inputs to eye movement control include prediction of future target velocity from extrapolation of past visual target movement and anticipation of future target movements. It is unclear whether non-visual input is impaired in patients with schizophrenia. We recorded smooth pursuit eye movements in 21 patients with schizophrenia spectrum disorder, 22 patients with bipolar disorder, and 24 controls. In a foveo-fugal ramp task, the target was either continuously visible or was blanked during movement. We determined peak gain (measuring overall performance), initial eye acceleration (measuring visually driven pursuit), deceleration after target extinction (measuring prediction), eye velocity drifts before onset of target visibility (measuring anticipation), and residual gain during blanking intervals (measuring anticipation and prediction). In both patient groups, initial eye acceleration was decreased and the ability to adjust eye acceleration to increasing target acceleration was impaired. In contrast, neither deceleration nor eye drift velocity was reduced in patients, implying unimpaired non-visual contributions to pursuit drive. Disturbances of eye movement control in psychotic disorders appear to be a consequence of deficits in sensorimotor transformation rather than a pure failure in adding cognitive contributions to pursuit drive in higher-order cortical circuits. More generally, this deficit might reflect a fundamental imbalance between processing external input and acting according to internal preferences.
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Affiliation(s)
| | - Andreas Sprenger
- Department of Neurology, University of Lübeck, Lübeck, Germany.,Institute of Psychology II, University of Lübeck, Lübeck, Germany
| | - Silke Talamo
- Department of Psychiatry and Psychotherapy, University of Lübeck, Lübeck, Germany
| | - Kirsten Herold
- Department of Neurology, University of Lübeck, Lübeck, Germany
| | | | - Rolf Verleger
- Department of Neurology, University of Lübeck, Lübeck, Germany.,Institute of Psychology II, University of Lübeck, Lübeck, Germany
| | - Rebekka Lencer
- Department of Psychiatry and Psychotherapy, University of Lübeck, Lübeck, Germany. .,Department of Psychiatry and Psychotherapy, University of Münster, Albert-Schweitzer-Campus 1, Geb. A9, 48149, Münster, Germany.
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17
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Lencer R, Sprenger A, Reilly JL, McDowell JE, Rubin LH, Badner JA, Keshavan MS, Pearlson GD, Tamminga CA, Gershon ES, Clementz BA, Sweeney JA. Pursuit eye movements as an intermediate phenotype across psychotic disorders: Evidence from the B-SNIP study. Schizophr Res 2015; 169:326-333. [PMID: 26481615 PMCID: PMC4681655 DOI: 10.1016/j.schres.2015.09.032] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Revised: 09/24/2015] [Accepted: 09/27/2015] [Indexed: 10/22/2022]
Abstract
Smooth pursuit eye tracking deficits are a promising intermediate phenotype for schizophrenia and possibly for psychotic disorders more broadly. The Bipolar-Schizophrenia Network on Intermediate Phenotypes (B-SNIP) consortium investigated the severity and familiality of different pursuit parameters across psychotic disorders. Probands with schizophrenia (N=265), schizoaffective disorder (N=178), psychotic bipolar disorder (N=231), their first-degree relatives (N=306, N=217, N=273, respectively) and healthy controls (N=305) performed pursuit tracking tasks designed to evaluate sensorimotor and cognitive/predictive aspects of pursuit. Probands from all diagnostic groups were impaired on all pursuit measures of interest compared to controls (p<0.001). Schizophrenia probands were more impaired than other proband groups on both early pursuit gain and predictive gain. Relatives with and without enhanced psychosis spectrum personality traits were impaired on initial eye acceleration, the most direct sensorimotor pursuit measure, but not on pursuit gain measures. This suggests that alterations in early sensorimotor function may track susceptibility to psychosis even in the absence of psychosis related personality traits. There were no differences in pursuit measures between relatives of the three proband groups. Familiality estimates of pursuit deficits indicate that early pursuit gain was more familial than predictive gain, which has been the most widely used measure in previous family studies of psychotic disorders. Thus, while disease-related factors may induce significant impairments of pursuit gain, especially in schizophrenia, the pattern of deficits in relatives and their familiality estimates suggest that alterations in sensorimotor function at pursuit onset may indicate increased susceptibility across psychotic disorders.
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Affiliation(s)
- Rebekka Lencer
- Department of Psychiatry and Psychotherapy, and Otto Creutzfeld Center, University of Muenster, Muenster, Germany
| | - Andreas Sprenger
- Department of Neurology, University of Luebeck, Luebeck, Germany
| | - James L. Reilly
- Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, USA
| | | | - Leah H. Rubin
- Department of Psychiatry, University of Illinois at Chicago, Chicago, USA
| | - Judith A. Badner
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, USA
| | - Matcheri S. Keshavan
- Department of Psychiatry, Harvard Medical School, Beth Israel Deacones Medical Center, Boston, USA
| | - Godfrey D. Pearlson
- Departments of Psychiatry and Neurobiology, Yale School of Medicine, and Olin Research Center, Institute of Living/Hartford Hospital, Hartford, USA
| | - Carol A. Tamminga
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, USA
| | - Elliot S. Gershon
- Department of Psychiatry and Behavioral Neuroscience, University of Chicago, Chicago, USA
| | | | - John A. Sweeney
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, USA
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Law PCF, Paton BK, Riddiford JA, Gurvich CT, Ngo TT, Miller SM. No Relationship Between Binocular Rivalry Rate and Eye-Movement Profiles in Healthy Individuals: A Bayes Factor Analysis. Perception 2015; 44:643-61. [DOI: 10.1177/0301006615594267] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Binocular rivalry (BR) is an intriguing phenomenon in which conflicting images are presented, one to each eye, resulting in perceptual alternations between each image. The rate of BR has been proposed as a potential endophenotype for bipolar disorder because (a) it is well established that this highly heritable psychiatric condition is associated with slower BR rate than in controls, and (b) an individual’s BR rate is approximately 50% genetically determined. However, eye movements (EMs) could potentially account for the slow BR trait given EM anomalies are observed in psychiatric populations, and there has been report of an association between saccadic rate and BR rate in healthy individuals. Here, we sought to assess the relationship between BR rate and EMs in healthy individuals ( N = 40, mean age = 34.4) using separate BR and EM tasks, with the latter measuring saccades during anticipatory, antisaccade, prosaccade, self-paced, free-viewing, and smooth-pursuit tasks. No correlation was found between BR rate and any EM measure for any BR task ( p > .01) with substantial evidence favoring this lack of association (BF01 > 3). This finding is in contrast to previous data and has important implications for using BR rate as an endophenotype. If replicated in clinical psychiatric populations, EM interpretations of the slow BR trait can be excluded.
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Affiliation(s)
- Phillip C. F. Law
- Monash Alfred Psychiatry Research Centre, Monash University Central Clinical School and The Alfred Hospital, Melbourne, Australia
| | - Bryan K. Paton
- School of Psychological Sciences, Monash University, Melbourne, Australia
- Philosophy and Cognition Lab, Philosophy Department, SOPHIS, Monash University, Melbourne, Victoria, Australia
- Monash Biomedical Imaging, Monash University, Melbourne, Victoria, Australia
| | - Jacqueline A. Riddiford
- Monash Alfred Psychiatry Research Centre, Monash University Central Clinical School and The Alfred Hospital, Melbourne, Australia
- School of Psychological Sciences, Monash University, Melbourne, Australia
| | - Caroline T. Gurvich
- Monash Alfred Psychiatry Research Centre, Monash University Central Clinical School and The Alfred Hospital, Melbourne, Australia
| | - Trung T. Ngo
- Monash Alfred Psychiatry Research Centre, Monash University Central Clinical School and The Alfred Hospital, Melbourne, Australia
- Genetic Epidemiology Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Steven M. Miller
- Monash Alfred Psychiatry Research Centre, Monash University Central Clinical School and The Alfred Hospital, Melbourne, Australia
- School of Psychological Sciences, Monash University, Melbourne, Australia
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Pearlson GD. Etiologic, Phenomenologic, and Endophenotypic Overlap of Schizophrenia and Bipolar Disorder. Annu Rev Clin Psychol 2015; 11:251-81. [DOI: 10.1146/annurev-clinpsy-032814-112915] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Godfrey D. Pearlson
- Departments of Psychiatry and Neurobiology, Yale University School of Medicine, New Haven, Connecticut 06510;
- Olin Neuropsychiatry Research Center, Hartford Healthcare Corporation, Hartford, Connecticut 06106
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Keedy SK, Bishop JR, Weiden PJ, Sweeney JA, Rosen C, Marvin R, Reilly JL. Disease and drug effects on internally-generated and externally-elicited responses in first episode schizophrenia and psychotic bipolar disorder. Schizophr Res 2014; 159:101-6. [PMID: 25112158 PMCID: PMC4177289 DOI: 10.1016/j.schres.2014.07.028] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 07/18/2014] [Accepted: 07/21/2014] [Indexed: 10/24/2022]
Abstract
Neurocognitive deficits are associated with most psychotic disorders, but may differ across diagnosis and by treatment status. This ambiguity is partly addressed in longitudinal pre/post treatment studies with first episode patients. Antipsychotic-naïve first-episode schizophrenia patients have shown intact performance on a predictive saccade task that assesses simple motor learning, spatial abilities, and response planning. After antipsychotic treatment, however, schizophrenia patients performing this task show a selective impairment in the accuracy of anticipatory responses, generated from learned internal representations of the task stimulus. This finding is in line with other observations of antipsychotic medication effects on frontostriatal systems, particularly dorsolateral prefrontal cortex. We sought to replicate this provocative finding with an independent sample of antipsychotic-naïve first-episode schizophrenia patients and extend it by including a group of patients with first episode bipolar disorder with psychosis (BDP). Matched healthy controls were also studied in parallel. Schizophrenia patients demonstrated intact performance pretreatment followed by impairment post-treatment for accuracy of anticipatory responses, and worse accuracy was associated with higher antipsychotic dose. BDP patients displayed saccade accuracy deficits before and after treatment and had no correlation of performance and antipsychotic dose. The findings suggest different neural alterations early in the course of each psychotic disorder, and different vulnerabilities to antipsychotic treatment effects between schizophrenia and BDP.
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Affiliation(s)
- Sarah K. Keedy
- Department of Psychiatry and Behavioral Neuroscience, 5841 S. Maryland Ave, MC3077, University of Chicago, IL, 60637,Corresponding author: ph. 773 834-7178, fax 773 834-4536
| | - Jeffrey R. Bishop
- Department of Pharmacy Practice, University of Illinois at Chicago, IL
| | - Peter J. Weiden
- Department of Psychiatry, University of Illinois at Chicago, IL
| | - John A. Sweeney
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX
| | - Cherise Rosen
- Department of Psychiatry, University of Illinois at Chicago, IL, United States.
| | - Robert Marvin
- Department of Psychiatry, University of Illinois at Chicago, IL, United States.
| | - James L. Reilly
- Department of Psychiatry and Behavioral Sciences, Northwestern University, Chicago, IL
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Association of variants in DRD2 and GRM3 with motor and cognitive function in first-episode psychosis. Eur Arch Psychiatry Clin Neurosci 2014; 264:345-55. [PMID: 24682224 PMCID: PMC4290665 DOI: 10.1007/s00406-013-0464-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2013] [Accepted: 10/16/2013] [Indexed: 12/16/2022]
Abstract
Similar smooth pursuit eye tracking dysfunctions are present across psychotic disorders. They include pursuit initiation and maintenance deficits that implicate different functional brain systems. This candidate gene study examined psychosis-related genotypes regulating dopamine and glutamate neurotransmission in relation to these pursuit deficits. One hundred and thirty-eight untreated first-episode patients with a psychotic disorder were genotyped for four markers in DRD2 and four markers in GRM3. The magnitude of eye movement abnormality in patients was defined in relation to performance of matched healthy controls (N = 130). Eighty three patients were followed after 6 weeks of antipsychotic treatment. At baseline, patients with a -141C deletion in DRD2 rs1799732 had slower initiation eye velocity and longer pursuit latency than CC insertion carriers. Further, GRM3 rs274622_CC carriers had poorer pursuit maintenance than T-carriers. Antipsychotic treatment resulted in prolonged pursuit latency in DRD2 rs1799732_CC insertion carriers and a decline in pursuit maintenance in GRM3 rs6465084_GG carriers. The present study demonstrates for the first time that neurophysiological measures of motor and neurocognitive deficits in patients with psychotic disorders have different associations with genes regulating dopamine and glutamate systems, respectively. Alterations in striatal D2 receptor activity through the -141C Ins/Del polymorphism could contribute to pursuit initiation deficits in psychotic disorders. Alterations in GRM3 coding for the mGluR3 protein may impair pursuit maintenance by compromising higher perceptual and cognitive processes that depend on optimal glutamate signaling in corticocortical circuits. DRD2 and GRM3 genotypes also selectively modulated the severity of adverse motor and neurocognitive changes resulting from antipsychotic treatment.
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Ivleva EI, Moates AF, Hamm JP, Bernstein IH, O’Neill HB, Cole D, Clementz BA, Thaker GK, Tamminga CA. Smooth pursuit eye movement, prepulse inhibition, and auditory paired stimuli processing endophenotypes across the schizophrenia-bipolar disorder psychosis dimension. Schizophr Bull 2014; 40:642-52. [PMID: 23599252 PMCID: PMC3984505 DOI: 10.1093/schbul/sbt047] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
BACKGROUND This study examined smooth pursuit eye movement (SPEM), prepulse inhibition (PPI), and auditory event-related potentials (ERP) to paired stimuli as putative endophenotypes of psychosis across the schizophrenia-bipolar disorder dimension. METHODS Sixty-four schizophrenia probands (SZP), 40 psychotic bipolar I disorder probands (BDP), 31 relatives of SZP (SZR), 26 relatives of BDP (BDR), and 53 healthy controls (HC) were tested. Standard clinical characterization, SPEM, PPI, and ERP measures were administered. RESULTS There were no differences between either SZP and BDP or SZR and BDR on any of the SPEM, PPI, or ERP measure. Compared with HC, SZP and BDP had lower SPEM maintenance and predictive pursuit gain and ERP theta/alpha and beta magnitudes to the initial stimulus. PPI did not differ between the psychosis probands and HC. Compared with HC, SZR and BDR had lower predictive pursuit gain and ERP theta/alpha and beta magnitudes to the first stimulus with differences ranging from a significant to a trend level. Neither active symptoms severity nor concomitant medications were associated with neurophysiological outcomes. SPEM, PPI, and ERP scores had low intercorrelations. CONCLUSION These findings support SPEM predictive pursuit and lower frequency auditory ERP activity in a paired stimuli paradigm as putative endophenotypes of psychosis common to SZ and BD probands and relatives. PPI did not differ between the psychosis probands and HC. Future studies in larger scale psychosis family samples targeting putative psychosis endophenotypes and underlying molecular and genetic mediators may aid in the development of biology-based diagnostic definitions.
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Affiliation(s)
- Elena I. Ivleva
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX;,*To whom correspondence should be addressed; 6363 Forest Park Road, BL6.106, Dallas, TX 75390-8828, US; tel: 214-648-0843, fax: 214-648-5321, e-mail:
| | - Amanda F. Moates
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX
| | - Jordan P. Hamm
- Departments of Psychology and Neuroscience, BioImaging Research Center, University of Georgia, Athens, GA
| | - Ira H. Bernstein
- Department of Clinical Sciences, University of Texas Southwestern Medical Center, Dallas, TX
| | - Hugh B. O’Neill
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Darwynn Cole
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX
| | - Brett A. Clementz
- Departments of Psychology and Neuroscience, BioImaging Research Center, University of Georgia, Athens, GA
| | - Gunvant K. Thaker
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Carol A. Tamminga
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX
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Sprenger A, Friedrich M, Nagel M, Schmidt CS, Moritz S, Lencer R. Advanced analysis of free visual exploration patterns in schizophrenia. Front Psychol 2013; 4:737. [PMID: 24130547 PMCID: PMC3795347 DOI: 10.3389/fpsyg.2013.00737] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Accepted: 09/23/2013] [Indexed: 11/13/2022] Open
Abstract
Background: Visual scanpath analyses provide important information about attention allocation and attention shifting during visual exploration of social situations. This study investigated whether patients with schizophrenia simply show restricted free visual exploration behavior reflected by reduced saccade frequency and increased fixation duration or whether patients use qualitatively different exploration strategies than healthy controls. Methods: Scanpaths of 32 patients with schizophrenia and age-matched 33 healthy controls were assessed while participants freely explored six photos of daily life situations (20 s/photo) evaluated for cognitive complexity and emotional strain. Using fixation and saccade parameters, we compared temporal changes in exploration behavior, cluster analyses, attentional landscapes, and analyses of scanpath similarities between both groups. Results: We found fewer fixation clusters, longer fixation durations within a cluster, fewer changes between clusters, and a greater increase of fixation duration over time in patients compared to controls. Scanpath patterns and attentional landscapes in patients also differed significantly from those of controls. Generally, cognitive complexity and emotional strain had significant effects on visual exploration behavior. This effect was similar in both groups as were physical properties of fixation locations. Conclusions: Longer attention allocation to a given feature in a scene and less attention shifts in patients suggest a more focal processing mode compared to a more ambient exploration strategy in controls. These visual exploration alterations were present in patients independently of cognitive complexity, emotional strain or physical properties of visual cues implying that they represent a rather general deficit. Despite this impairment, patients were able to adapt their scanning behavior to changes in cognitive complexity and emotional strain similar to controls.
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Verleger R, Talamo S, Simmer J, Śmigasiewicz K, Lencer R. Neurophysiological sensitivity to attentional overload in patients with psychotic disorders. Clin Neurophysiol 2013; 124:881-92. [DOI: 10.1016/j.clinph.2012.11.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 11/05/2012] [Accepted: 11/06/2012] [Indexed: 10/27/2022]
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Enhanced top-down control during pursuit eye tracking in schizophrenia. Eur Arch Psychiatry Clin Neurosci 2013; 263:223-31. [PMID: 22639244 DOI: 10.1007/s00406-012-0332-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2012] [Accepted: 05/14/2012] [Indexed: 10/28/2022]
Abstract
Alterations in sensorimotor processing and predictive mechanisms have both been proposed as the primary cause of eye tracking deficits in schizophrenia. 20 schizophrenia patients and 20 healthy controls were assessed on blocks of predictably moving visual targets at constant speeds of 10, 15 or 30°/s. To assess internal drive to the eye movement system based on predictions about the ongoing target movement, targets were blanked off for either 666 or 1,000 ms during the ongoing pursuit movement in additional conditions. Main parameters of interest were eye deceleration after extinction of the visual target and residual eye velocity during blanking intervals. Eye deceleration after target extinction, reflecting persistence of predictive signals, was slower in patients than in controls, implying greater rather than diminished utilization of predictive mechanisms for pursuit in schizophrenia. Further, residual gain was not impaired in patients indicating a basic integrity of internal predictive models. Pursuit velocity gain in patients was reduced in all conditions with visible targets replicating previous findings about a sensorimotor transformation deficit in schizophrenia. A pattern of slower eye deceleration and unimpaired residual gain during blanking intervals implies greater adherence to top-down predictive models for pursuit tracking in schizophrenia. This suggests that predictive modeling is relatively intact in schizophrenia and that the primary cause of abnormal visual pursuit is impaired sensorimotor transformation of the retinal error signal needed for the maintenance of accurate visually driven pursuit. This implies that disruption in extrastriate and sensorimotor systems rather than frontostriatal predictive mechanisms may underlie this widely reported endophenotypes for schizophrenia.
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Moates AF, Ivleva EI, O’Neill HB, Krishna N, Cullum CM, Thaker GK, Tamminga CA. Predictive pursuit association with deficits in working memory in psychosis. Biol Psychiatry 2012; 72:752-7. [PMID: 22554452 PMCID: PMC3427716 DOI: 10.1016/j.biopsych.2012.03.030] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/16/2011] [Revised: 03/28/2012] [Accepted: 03/28/2012] [Indexed: 11/27/2022]
Abstract
BACKGROUND Deficits in smooth pursuit eye movements are an established phenotype for schizophrenia (SZ) and are being investigated as a potential liability marker for bipolar disorder. Although the molecular determinants of this deficit are still unclear, research has verified deficits in predictive pursuit mechanisms in SZ. Because predictive pursuit might depend on the working memory system, we have hypothesized a relationship between the two in healthy control subjects (HC) and SZ and here examine whether it extends to psychotic bipolar disorder (BDP). METHODS Volunteers with SZ (n = 38), BDP (n = 31), and HC (n = 32) performed a novel eye movement task to assess predictive pursuit as well as a standard visuospatial measure of working memory. RESULTS Individuals with SZ and BDP both showed reduced predictive pursuit gain compared with HC (p < .05). Moreover, each patient group showed worse performance in visuospatial working memory compared with control subjects (p < .05). A strong correlation (r = .53, p = .007) was found between predictive pursuit gain and working memory in HC, a relationship that showed a trend correlation within the BDP group but not among SZ. CONCLUSIONS Individuals with SZ and BDP showed similar deficits in predictive pursuit, suggesting that this alteration could be a characteristic trait of the psychosis domain. The correlation between predictive pursuit and working memory in HC supports the assumption that working memory is related to predictive pursuit eye movements; however, the degradation of working memory in people with psychosis disrupts its association with eye-tracking behavior.
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Affiliation(s)
- Amanda F. Moates
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX,Correspondence: Amanda F. Moates, Ph.D., Department of Psychiatry, UT Southwestern Medical Center, 6363 Forest Park Road, Dallas, TX 75390 - 8828, Phone 214 648 5253, Fax 214 648 5321,
| | - Elena I. Ivleva
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX
| | - Hugh B. O’Neill
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Nithin Krishna
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - C. Munro Cullum
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX
| | - Gunvant K. Thaker
- Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD
| | - Carol A. Tamminga
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX
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Nagel M, Sprenger A, Steinlechner S, Binkofski F, Lencer R. Altered velocity processing in schizophrenia during pursuit eye tracking. PLoS One 2012; 7:e38494. [PMID: 22693639 PMCID: PMC3367930 DOI: 10.1371/journal.pone.0038494] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 05/07/2012] [Indexed: 11/18/2022] Open
Abstract
Smooth pursuit eye movements (SPEM) are needed to keep the retinal image of slowly moving objects within the fovea. Depending on the task, about 50%-80% of patients with schizophrenia have difficulties in maintaining SPEM. We designed a study that comprised different target velocities as well as testing for internal (extraretinal) guidance of SPEM in the absence of a visual target. We applied event-related fMRI by presenting four velocities (5, 10, 15, 20°/s) both with and without intervals of target blanking. 17 patients and 16 healthy participants were included. Eye movements were registered during scanning sessions. Statistical analysis included mixed ANOVAs and regression analyses of the target velocity on the Blood Oxygen Level Dependency (BOLD) signal. The main effect group and the interaction of velocity×group revealed reduced activation in V5 and putamen but increased activation of cerebellar regions in patients. Regression analysis showed that activation in supplementary eye field, putamen, and cerebellum was not correlated to target velocity in patients in contrast to controls. Furthermore, activation in V5 and in intraparietal sulcus (putative LIP) bilaterally was less strongly correlated to target velocity in patients than controls. Altered correlation of target velocity and neural activation in the cortical network supporting SPEM (V5, SEF, LIP, putamen) implies impaired transformation of the visual motion signal into an adequate motor command in patients. Cerebellar regions seem to be involved in compensatory mechanisms although cerebellar activity in patients was not related to target velocity.
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Affiliation(s)
- Matthias Nagel
- Department of Psychiatry and Psychotherapy, University of Luebeck, Luebeck, Germany.
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Grynszpan O, Simonin J, Martin JC, Nadel J. Investigating social gaze as an action-perception online performance. Front Hum Neurosci 2012; 6:94. [PMID: 22529796 PMCID: PMC3330759 DOI: 10.3389/fnhum.2012.00094] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Accepted: 04/02/2012] [Indexed: 11/13/2022] Open
Abstract
Gaze represents a major non-verbal communication channel in social interactions. In this respect, when facing another person, one's gaze should not be examined as a purely perceptive process but also as an action-perception online performance. However, little is known about processes involved in the real-time self-regulation of social gaze. The present study investigates the impact of a gaze-contingent viewing window on fixation patterns and the awareness of being the agent moving the window. In face-to-face scenarios played by a virtual human character, the task for the 18 adult participants was to interpret an equivocal sentence which could be disambiguated by examining the emotional expressions of the character speaking. The virtual character was embedded in naturalistic backgrounds to enhance realism. Eye-tracking data showed that the viewing window induced changes in gaze behavior, notably longer visual fixations. Notwithstanding, only half of the participants ascribed the window displacements to their eye movements. These participants also spent more time looking at the eyes and mouth regions of the virtual human character. The outcomes of the study highlight the dissociation between non-volitional gaze adaptation and the self-ascription of agency. Such dissociation provides support for a two-step account of the sense of agency composed of pre-noetic monitoring mechanisms and reflexive processes, linked by bottom-up and top-down processes. We comment upon these results, which illustrate the relevance of our method for studying online social cognition, in particular concerning autism spectrum disorders (ASD) where the poor pragmatic understanding of oral speech is considered linked to visual peculiarities that impede facial exploration.
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Affiliation(s)
- Ouriel Grynszpan
- Centre National de la Recherche Scientifique, CNRS-USR 3246, Université Pierre et Marie Curie, Hôpital de La Salpêtrière Paris, France
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A ticking clock for the production of sequential actions: where does the problem lie in schizophrenia? Schizophr Res 2012; 135:51-4. [PMID: 22260961 DOI: 10.1016/j.schres.2011.12.020] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Revised: 12/11/2011] [Accepted: 12/25/2011] [Indexed: 11/20/2022]
Abstract
Schizophrenia has been associated to a distorted time clock. By subtracting contact duration from Inter Response Interval, we report evidence for preserved internal clock in schizophrenia, with normal spontaneous tapping tempo. Contact durations were however increased in patients suggesting a specific problem in the fast integration of incoming haptic feedback with outgoing motor efferences. This integration deficit would emerge at an early phase, since Ultra High Risk patients also revealed abnormal tapping stability. Tactile screens revealed to be a simple and low cost apparatus that may constitute a suitable measuring kit for the characterisation of sensory motor deficits in clinical settings.
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Wilens TE, Morrison NR, Prince J. An update on the pharmacotherapy of attention-deficit/hyperactivity disorder in adults. Expert Rev Neurother 2012; 11:1443-65. [PMID: 21955201 DOI: 10.1586/ern.11.137] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Adults with attention-deficit/hyperactivity disorder (ADHD) are more frequently presenting for diagnosis and treatment. Medication is considered to be appropriate among available treatments for ADHD; however, the evidence supporting the use of pharmacotherapeutics for adults with ADHD remains less established. In this article, the effectiveness and dosing parameters of the various agents investigated for adult ADHD are reviewed. In adults with ADHD, short-term improvements in symptomatology have been documented through the use of stimulants and antidepressants. Studies suggest that methylphenidate and amphetamine maintained an immediate onset of action, whereas the ADHD response to the nonstimulants appeared to be delayed. At a group level, there appears to be some, albeit not entirely consistent, dose-dependent responses to amphetamine and methylphenidate. Generally speaking, variability in diagnostic criteria, dosing parameters and response rates between the various studies was considerable, and most studies were of a relatively short duration. The aggregate literature shows that the stimulants and catecholaminergic nonstimulants investigated had a clinically significant beneficial effect on treating ADHD in adults.
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Affiliation(s)
- Timothy E Wilens
- Clinical Research Program in Pediatric Psychopharmacology, Child Psychiatry Service, Massachusetts General Hospital, Boston, MA, USA.
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Lencer R, Keedy SK, Reilly JL, McDonough BE, Harris MSH, Sprenger A, Sweeney JA. Altered transfer of visual motion information to parietal association cortex in untreated first-episode psychosis: implications for pursuit eye tracking. Psychiatry Res 2011; 194:30-8. [PMID: 21873035 PMCID: PMC3185164 DOI: 10.1016/j.pscychresns.2011.06.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Revised: 05/12/2011] [Accepted: 06/17/2011] [Indexed: 11/19/2022]
Abstract
Visual motion processing and its use for pursuit eye movement control represent a valuable model for studying the use of sensory input for action planning. In psychotic disorders, alterations of visual motion perception have been suggested to cause pursuit eye tracking deficits. We evaluated this system in functional neuroimaging studies of untreated first-episode schizophrenia (N=24), psychotic bipolar disorder patients (N=13) and healthy controls (N=20). During a passive visual motion processing task, both patient groups showed reduced activation in the posterior parietal projection fields of motion-sensitive extrastriate area V5, but not in V5 itself. This suggests reduced bottom-up transfer of visual motion information from extrastriate cortex to perceptual systems in parietal association cortex. During active pursuit, activation was enhanced in anterior intraparietal sulcus and insula in both patient groups, and in dorsolateral prefrontal cortex and dorsomedial thalamus in schizophrenia patients. This may result from increased demands on sensorimotor systems for pursuit control due to the limited availability of perceptual motion information about target speed and tracking error. Visual motion information transfer deficits to higher-level association cortex may contribute to well-established pursuit tracking abnormalities, and perhaps to a wider array of alterations in perception and action planning in psychotic disorders.
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Affiliation(s)
- Rebekka Lencer
- Center for Cognitive Medicine, University of Illinois at Chicago, USA
- Department of Psychiatry and Psychotherapy, University of Luebeck
- Department of Psychiatry and Psychotherapy, University of Muenster, Germany
| | - Sarah K. Keedy
- Center for Cognitive Medicine, University of Illinois at Chicago, USA
| | - James L. Reilly
- Center for Cognitive Medicine, University of Illinois at Chicago, USA
| | | | | | | | - John A. Sweeney
- Center for Cognitive Medicine, University of Illinois at Chicago, USA
- Corresponding author: John A. Sweeney, PhD, Center for Cognitive Medicine, University of Illinois at Chicago, 912 S Wood St., M/C 913, Chicago, IL 60612, USA, , Phone (312) 355-1582, Fax (312) 413-8837
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Martin LF, Olincy A, Ross RG, Du YP, Singel D, Shatti S, Tregellas JR. Cerebellar hyperactivity during smooth pursuit eye movements in bipolar disorder. J Psychiatr Res 2011; 45:670-7. [PMID: 20950824 DOI: 10.1016/j.jpsychires.2010.09.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 09/14/2010] [Accepted: 09/21/2010] [Indexed: 11/30/2022]
Abstract
INTRODUCTION Smooth pursuit eye movements (SPEM) are abnormal in individuals with schizophrenia and individuals with bipolar disorder. Functional imaging methods have revealed greater hippocampal activity and less frontotemporal, visual, and posterior cerebellar activity in individuals with schizophrenia when performing a SPEM task. The underlying neurobiology of SPEM deficits in bipolar disorder is unknown. METHODS Functional magnetic resonance imaging at 3T was performed on fourteen subjects with bipolar disorder and 14 subjects without psychiatric illness during a block design SPEM task. Clinical measures were assessed on the day of testing and related to imaging measures. RESULTS Subjects with bipolar disorder had greater hemodynamic response than control subjects in cerebellar vermis. Responses were associated with levels of depressive symptoms on the day of study. DISCUSSION Increased cerebellar vermis activity during the smooth pursuit eye movement task in individuals with bipolar disorder further implicates cerebellar involvement in bipolar disorder. Increased hemodynamic response within the hippocampus was not seen in these individuals and may be a finding specific to schizophrenia.
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Affiliation(s)
- Laura Frances Martin
- University of Colorado Denver School of Medicine, Pscyhiatry, Mail Stop F546, 13001 E. 17th Place, Aurora, CO 80045, USA.
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Mosconi MW, Kay M, D'Cruz AM, Guter S, Kapur K, Macmillan C, Stanford LD, Sweeney JA. Neurobehavioral abnormalities in first-degree relatives of individuals with autism. ACTA ACUST UNITED AC 2010; 67:830-40. [PMID: 20679591 DOI: 10.1001/archgenpsychiatry.2010.87] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Studying sensorimotor and neurocognitive impairments in unaffected family members of individuals with autism may help identify familial pathophysiological mechanisms associated with the disorder. OBJECTIVE To determine whether atypical sensorimotor or neurocognitive characteristics associated with autism are present in first-degree relatives of individuals with autism. DESIGN Case-control comparison of neurobehavioral functions. SETTING University medical center. PARTICIPANTS Fifty-seven first-degree relatives of individuals with autism and 40 age-, sex-, and IQ-matched healthy control participants (aged 8-54 years). MAIN OUTCOME MEASURES Oculomotor tests of sensorimotor responses (saccades and smooth pursuit); procedural learning and response inhibition; neuropsychological tests of motor, memory, and executive functions; and psychological measures of social behavior, communication skills, and obsessive-compulsive behaviors. RESULTS On eye movement testing, family members demonstrated saccadic hypometria, reduced steady-state pursuit gain, and a higher rate of voluntary response inhibition errors relative to controls. They also showed lateralized deficits in procedural learning and open-loop pursuit gain (initial 100 milliseconds of pursuit) and increased variability in the accuracy of large-amplitude saccades that were confined to rightward movements. In neuropsychological studies, only executive functions were impaired relative to those of controls. Family members reported more communication abnormalities and obsessive-compulsive behaviors than controls. Deficits across oculomotor, neuropsychological, and psychological domains were relatively independent from one another. CONCLUSIONS Family members of individuals with autism demonstrate oculomotor abnormalities implicating pontocerebellar and frontostriatal circuits and left-lateralized alterations of frontotemporal circuitry and striatum. The left-lateralized alterations have not been identified in other neuropsychiatric disorders and are of interest given atypical brain lateralization and language development associated with the disorder. Similar oculomotor deficits have been reported in individuals with autism, suggesting that they may be familial and useful for studies of neurophysiological and genetic mechanisms in autism.
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Affiliation(s)
- Matthew W Mosconi
- Center for Cognitive Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
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