Is conflict adaptation disrupted in schizophrenia? An ERP study

OBJECTIVE: The present study investigated the congruency sequence effect (CSE), a key marker of conflict adaptation, in individuals with schizophrenia (SZ). Given the cognitive control deficits associated with SZ, we examined whether the CSE is preserved in SZ using a confound-minimized Flanker task. METHODS: 19 SZs and 19 healthy controls (HC) performed a Flanker task with congruent and incongruent trials. Error trials, post-error trials, and response repetitions were excluded. Reaction times, accuracy, and event-related potentials (P2, N2, P3) were analysed as a function of current and previous trial congruency. RESULTS: Both groups exhibited flanker effect and a CSE: responses were faster and more accurate for congruent than incongruent trials, and after congruent compared with incongruent trials. SZs were slower overall, but the pattern and magnitude of the CSE did not differ between groups. Electrophysiologically, incongruent trials elicited larger N2 and P3 amplitudes, and previous-trial congruency modulated N2, P2, and P3. No group differences emerged in ERP amplitudes. CONCLUSION: SZs demonstrate behavioural and neural patterns of conflict adaptation comparable to HCs. These findings suggest that, despite evidence of functional abnormalities in brain regions associated with conflict detection and adaptation, the CSE may be preserved in medicated SZs.