The brain activation maps using fMRI during reflexive saccades and antisaccades in schizophrenia

Abstract

[Introduction] The aim of the present study is to compare the brain activation maps using fMRI between normal controls and schizophrenic patients during saccade and antisaccade tasks for detecting the neural network dysfunction in schizophrenia. [Subjects and Methods] Right-handed nine schizophrenic patients who showed good performance, nine schizophrenic patients with poor performance and nine healthy volunteers participated in this study. All the subjects were given written informed consent.During the saccade and antisaccade task, fixation point offset occurred after 500-1500 ms before a peripheral target appeared for a duration of 1000 ms. While subjects performed either the saccade or antisaccade task and baseline control tasks, fMRI scans were obtained. [Results and Conclusion] Cortical activations in the front-parietal network depended on the antisaccade task performance in schizophrenic patients. On the other hand, sub-cortical activations in the strieto-thlamic circuit were found only in the control group.Dysfunction of the striato-thalamo-cortical dopaminergic circuitry may reduce inhibition and thus facilitate saccades in schizophrenia. [Jpn J Physiol 54 Suppl:S191 (2004)]