Sustained attention ability in schizophrenia: Investigation of conflict monitoring mechanisms.

OBJECTIVE: The main goal of the current study was to assess, with a time-on-task approach, sustained attention ability in schizophrenia, and to investigate conflict monitoring underlying this ability.

METHODS: Behavioral and event-related potentials data (N2 and P3a amplitudes) were recorded in a long-lasting sustained attention Go/NoGo task (sustained attention to response task, SART), over a period of 30min, in 29 patients with schizophrenia and 29 pair-matched healthy subjects.

RESULTS: Our results revealed spared sustained attention ability in patients throughout the task. Impairment of conflict detection (N2) in patients was particularly significant at the end of the task. Furthermore, both schizophrenia and healthy subjects exhibited a decline in conflict detection from the beginning to the middle of the task. Whereas controls' conflict detection recovered in the last part of the task, patients' did not, suggesting a deficit in recovery processes reflecting a lack of additional resources sustained attention Go/NoGo task. Conflict resolution (P3a) was preserved throughout the task in both groups.

CONCLUSIONS: Conflict monitoring processes are increasingly impaired in schizophrenia during a long-lasting sustained attention Go/NoGo task.

SIGNIFICANCE: This impairment at the end of the task may rely on deficit in recovery processes, rather than a deficit in conflict detection per se in schizophrenia.