Abstract：Objective: Task-induced deactivations(TIDs) of cortical regions may reflect elements of a “default-mode” of brain function associated with self-directed mental processes at rest. TID phenomenon in schizophrenia and its relevance to patients’ emotional state and task performance were examined. Materials and Methods: Fifteen schizophrenic patients and matched control subjects were studied in a fMRI design of 2-back working memory task. Positive and negative affect scale scores were calculated for every individuals. Results: Relative to control subjects, patients showed significantly prolonged reaction time, lower TID of the medial prefrontal cortex and posterior medial cortex, and higher negative emotional scores. The magnitude of the TID for medial prefrontal cortex was associated negatively with patients’ reaction time and negative emotional scale. Conclusion: Shift efficiency of attention resource between cognitive and emotional state is impaired, which is probably one of the neural mechanism of cognitive function impairment for schizophrenic patients.
2009, Vol. 20 
