Sequential neural changes during motor learning in schizophrenia.
Positron emission tomography (PET) was used to investigate differences in neural plasticity associated with learning a unique motor task in patients with schizophrenia and healthy volunteers. Working with a robotic manipulandum, subjects learned reaching movements in a force field. Visual cues were provided to guide the reaching movements. PET rCBF measures were acquired while participants learned the motor skill over successive runs. The groups did not differ in behavioral performance but did differ in their rCBF activity patterns. Healthy volunteers displayed blood flow increases in primary motor cortex and supplementary motor area with motor learning. The patients with schizophrenia displayed an increase in the primary visual cortex with motor learning. Changes in these regions were positively correlated with changes in each group's motor accuracy, respectively. This is the first study to employ a unique arm-reaching motor learning test to assess neural plasticity during multiple phases of motor learning in patients with schizophrenia. The patients may have an inability to rapidly tune motor cortical neural populations to a preferred direction. The visual system, however, appears to be highly compensated in schizophrenia and the inability to rapidly modulate the motor cortex may be substantially corrected by the schizophrenic group's visuomotor adaptations.
Rowland
Laura M
LM
Maryland Psychiatric Research Center and Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD 21228, USA.
Shadmehr
Reza
R
Kravitz
Dwight
D
Holcomb
Henry H
HH
D000328:Adult; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging*; D001931:Brain Mapping; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D007091:Image Processing, Computer-Assisted; D017774:Long-Term Potentiation / Q000502:physiology; D008297:Male; D009044:Motor Cortex / Q000098:blood supply / Q000000981:diagnostic imaging*; D009048:Motor Skills / Q000502:physiology*; D009473:Neuronal Plasticity / Q000502:physiology*; D020534:Parahippocampal Gyrus / Q000000981:diagnostic imaging / Q000503:physiopathology; D049268:Positron-Emission Tomography; D011214:Practice, Psychological; D017397:Prefrontal Cortex / Q000098:blood supply / Q000000981:diagnostic imaging*; D011597:Psychomotor Performance / Q000502:physiology*; D012016:Reference Values; D012039:Regional Blood Flow / Q000502:physiology; D012371:Robotics; D012559:Schizophrenia / Q000000981:diagnostic imaging* / Q000503:physiopathology; D014793:Visual Cortex / Q000000981:diagnostic imaging / Q000503:physiopathology