title: Neuronal substrate and effective connectivity of abnormal movement sequencing in schizophrenia.
abstract: Movement sequencing difficulties are part of the neurological soft signs (NSS), they have high clinical value because they are not always present in schizophrenia. We investigated the neuronal correlates of movement sequencing in 24 healthy controls and 24 schizophrenia patients, with (SZP SQ+) or without (SZP SQ-) sequencing difficulties. We characterized simultaneous and lagged functional connectivity between brain regions involved in movement sequencing using psychophysiological interaction (PPI) and the Granger causality modeling (GCM), respectively. Left premotor cortex (PMC) and superior parietal lobule (SPL) were specifically activated during sequential movements in all participants. Right PMC and precuneus, ipsilateral to the hand executing the task, activated during sequential movements only in healthy controls and SZP SQ-. SZP SQ+ showed hyperactivation in contralateral PMC, as compared to the other groups. PPI analysis revealed a deficit in inhibitory connections within this fronto-parietal network in SZP SQ+ during sequential task. GCM showed a significant lagged effective connectivity from right PMC to left SPL during task and rest periods in all groups and from right PMC to right precuneus in SZP SQ+ group only. Both SZP groups had a significant lagged connectivity from right to left PMC, during sequential task. Our results indicate that aberrant fronto-parietal network connectivity with cortical inhibition deficit and abnormal reliance on previous network activity are related to movement sequencing in SZP. The overactivation of motor cortex seems to be a good compensating strategy, the hyperactivation of parietal cortex is linked to motor deficit symptoms.
authors.affiliation: Behavioural and Social Neuroscience Research Group, Central European Institute of Technology - Masaryk University, Brno, Czech Republic. Electronic address: petra.zemankova@ceitec.muni.cz.
authors.forename: Petra
authors.initials: P
authors.lastname: Zemankova
authors.affiliation: Department of Psychiatry, University of Montreal, Centre de recherche de l'Institut Universitaire de Gériatrie de Montreal, Montreal, Canada; Centre for Research in Aging, Donald Berman Maimonides Geriatric Centre, Montreal, Canada.
authors.forename: Ovidiu
authors.initials: O
authors.lastname: Lungu
authors.affiliation: Department of Psychiatry, Faculty of Medicine of the Masaryk University and University Hospital Brno, Brno, Czech Republic.
authors.forename: Jitka
authors.initials: J
authors.lastname: Huttlova
authors.affiliation: Department of Radiology, Faculty of Medicine of the Masaryk University and University Hospital Brno, Brno, Czech Republic.
authors.forename: Milos
authors.initials: M
authors.lastname: Kerkovsky
authors.affiliation: Department of Psychiatry, Faculty of Medicine of the Masaryk University and University Hospital Brno, Brno, Czech Republic.
authors.forename: Jozef
authors.initials: J
authors.lastname: Zubor
authors.affiliation: Department of Psychiatry, Faculty of Medicine of the Masaryk University and University Hospital Brno, Brno, Czech Republic.
authors.forename: Petra
authors.initials: P
authors.lastname: Lipova
authors.affiliation: Behavioural and Social Neuroscience Research Group, Central European Institute of Technology - Masaryk University, Brno, Czech Republic; First Department of Neurology, Faculty of Medicine of the Masaryk University and St. Anne's University Hospital, Brno, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Bares
authors.affiliation: Behavioural and Social Neuroscience Research Group, Central European Institute of Technology - Masaryk University, Brno, Czech Republic; Department of Psychiatry, Faculty of Medicine of the Masaryk University and University Hospital Brno, Brno, Czech Republic.
authors.forename: Tomas
authors.initials: T
authors.lastname: Kasparek
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging; D001931:Brain Mapping; D018450:Disease Progression; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D009069:Movement Disorders / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology*; D009434:Neural Pathways / Q000000981:diagnostic imaging; D011597:Psychomotor Performance / Q000502:physiology; D011602:Psychophysiologic Disorders / Q000000981:diagnostic imaging / Q000209:etiology*; D012559:Schizophrenia / Q000150:complications*; D055815:Young Adult
keywords: Effective connectivity; Movement sequencing; Neurological soft signs; Schizophrenia; fMRI