Abstract
BACKGROUND: Patients with major depression (MD) exhibit conditional reasoning dysfunction; however, no studies on the event-related potential (ERP) characteristics of conditional reasoning in MD have been reported. AIM: To investigate the ERP characteristics of conditional reasoning in MD patients and explore the neural mechanism of cognitive processing. METHODS: Thirty-four patients with MD and 34 healthy controls (HCs) completed ERP measurements while performing the Wason selection task (WST). The cluster-based permutation test in FieldTrip was used to compare the differences in the mean amplitudes between the patients with MD and HCs on the ERP components under different experimental conditions. Behavioral data [accuracy (ACC) and reaction times (RTs)], the ERP P100 and late positive potentials (LPPs) were analyzed. RESULTS: Although the mean ACC was greater and the mean of RTs was shorter in HCs than in MD patients, the differences were not statistically significant. However, across both groups, the ACC in the precautionary WST was greater than that in the other tasks, and the RTs in the abstract task were greater than those in the other tasks. Importantly, compared with that of HCs, the P100 of the left centroparietal sites was significantly increased, and the early LPP was attenuated at parietal sites and increased at left frontocentral sites; the medium LPP and late LPP were increased at the left frontocentral sites. CONCLUSION: Patients with MD have conditional reasoning dysfunction and exhibit abnormal ERP characteristics evoked by the WST, which suggests neural correlates of abnormalities in conditional reasoning function in MD patients.