P61-F Implicit and explicit emotional modulation of visual ERPs in female patients with major depressive disorder

Background We aimed at searching for the ERP characteristics that may differentiate the patients with major depressive disorder (MDD) from healthy controls (HC). Changes in ERP components due to the implicit and explicit emotion recognition were explored. We also took into account the growing evidence of gender specificity in MDD. Materials and methods Only female participants took part in our study: 30 non-medicated patients with MDD and 54 HC. Participants had to sort 160 photographs: first as humans or animals (Implicit task), and then as neutral or aggressive (Explicit task). Half of the photographs were neutral, and half were showing angry/aggressive people or animals. We recorded 128-channel EEG and analyzed the ERPs elicited by human images. The difference ( p Results Robust EM in N170 component was found in both groups and both tasks; the amplitude changes (voltage increase for angry faces) and the scalp topography of EM were similar in HC in both tasks, but in MDD they were seen in a lesser degree in Explicit task. The EM in components peaking around 300–350 ms was also showing group and task specificity. The components in the range of 400–600 ms showed EM mostly in central (in HC) and fronto-central (in MDD) areas. Conclusions The study of implicit emotional processes and their comparison to the explicit processes seems to be a promising direction in our search for the biomarkers to distinguish healthy and pathological brain activity.