title: Effects of object size on unimanual and bimanual movements in patients with schizophrenia.
abstract: Schizophrenia affects not only mental function but also movement. We compared the movement of patients with mild schizophrenia and healthy control participants during a bimanual assembly task and examined whether changes in object size affected unimanual and bimanual movements. Fifteen patients with schizophrenia and 15 age- and gender-matched control participants were instructed to bimanually reach for and assemble objects. We manipulated the object size for the left hand (large vs. small) and measured movement time, peak velocity, and bimanual synchronization to represent movement speed, forcefulness, and bimanual coordination. Patients with schizophrenia showed slower and less forceful unimanual movements and less coordinated bimanual movements than control participants. Increasing the object size elicited faster and more forceful unimanual movements and more coordinated bimanual movements in patients. The results suggest the need for movement rehabilitation in patients with schizophrenia and the possibility of manipulating object size to optimize patients' movements. These results benefit the practice of evidence-based therapy.
authors.affiliation: Shu-Mei Wang, MS, OT, is Doctoral Candidate, Institute of Allied Health Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Shu-Mei
authors.initials: SM
authors.lastname: Wang
authors.affiliation: Li-Chieh Kuo, PhD, OT, is Associate Professor, Department of Occupational Therapy and Institute of Allied Health Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Li-Chieh
authors.initials: LC
authors.lastname: Kuo
authors.affiliation: Wen-Chen Ouyang, PhD, MD, is Director, Department of Geriatric Psychiatry, Jianan Mental Hospital, Department of Health, Executive Yuan, Tainan, Taiwan.
authors.forename: Wen-Chen
authors.initials: WC
authors.lastname: Ouyang
authors.affiliation: Hsiao-Man Hsu, MS, OT, is Doctoral Candidate, Institute of Biomedical Engineering, College of Engineering, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Hsiao-Man
authors.initials: HM
authors.lastname: Hsu
authors.affiliation: Keh-Chung Lin, ScD, OTR, is Professor, School of Occupational Therapy, College of Medicine, National Taiwan University, Taipei.
authors.forename: Keh-Chung
authors.initials: KC
authors.lastname: Lin
authors.affiliation: Hui-Ing Ma, ScD, OT, is Professor, Department of Occupational Therapy and Institute of Allied Health Sciences, College of Medicine, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan; huingma@mail.ncku.edu.tw.
authors.forename: Hui-Ing
authors.initials: HI
authors.lastname: Ma
mesh_terms: D000328:Adult; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D009068:Movement; D009788:Occupational Therapy / Q000379:methods*; D011597:Psychomotor Performance; D012559:Schizophrenia / Q000503:physiopathology* / Q000534:rehabilitation*