Investigation of Brain Performance in the Schizophrenia Spectrum Using EEG with Mental and Temporal Effort

Schizophrenia Spectrum Disorder, widely known as causing behavioral changes, deprives many professionals—who remain capable of working—their jobs. This study aimed to investigate the use of electroencephalography exam (EEG) combined with standardized mental effort sequence as a complementary tool for clinical diagnosis and to monitor the treatment response in individuals with schizophrenia and those who want to return to professional activities. EEG recordings were acquired before (IR_Initial Register) and after (FR_Final Register) the completion of a set of timed mental effort tasks in a group of 25 clinically stable individuals diagnosed with schizophrenia with positive symptoms and an 11-member healthy volunteer control group. Data from both groups were compared using temporal and spectral descriptors, and the results were analyzed statistically. The results revealed that, in the FR phase, the Vtotal parameter for the schizophrenia group was 7.89% lower, and the frequency parameter was 16.35% lower than in the healthy group. Notable differences were observed in the tolerance parameter for the duration of sustained cognitive effort: 57.9% of healthy volunteers sustained 100% of the effort duration, compared with 6.1% of volunteers with schizophrenia.