Over the past several decades numerous studies using multiple methodologies have suggested lateralized abnormalities in schizophrenia. Although there are many discrepant results, the most consistent findings have suggested abnormalities in left hemisphere (LH) structure or functioning. In studies of neuroleptic-naÃ¯ve patients with schizophrenia and first degree family members of schizophrenia patients, we have found that over one-third of individuals have significant asymmetries in their ability to maintain steady-state force (force instability), with the substantial majority of patients and family members demonstrating greater left hemisphere (right hand) than right hemisphere (left hand) instability. These results suggest that a proportion of patients with schizophrenia and family members have greater left hemisphere than right hemisphere involvement in motor control pathways, possibly related to asymmetrical functioning of the basal ganglia.
Keywords: schizophrenia, dyskinesia, extrapyramidal