Neural evidence for compromised mental imagery in individuals with chronic schizophrenia.

Mental imagery impairment has been reported in schizophrenia. The present study aimed to investigate the neural evidence for mental imagery impairment in patients with schizophrenia. The study participants included 20 patients with chronic schizophrenia and 18 healthy control subjects. Event-related potentials were recorded during a mental hand rotation task, in which participants were instructed to judge the laterality of hands displayed in different orientations. The performances of patients were significantly less accurate and slower than control subjects on hand rotation task. Moreover, the patients showed significantly reduced rotation-related negativity amplitude for mental rotation effect. The results demonstrate mental imagery impairment in patients with schizophrenia at both the behavioral and neural levels.