Feasibility to Use the Visual Oddball Paradigm with Emotional Faces to Passive Test of Emotional Reaction

Abstract

There is a growing interest in the development of objective methods for assessing psychoemotional states. The present study proposes an electroencephalography (EEG) based approach for identifying neurophysiological markers of emotional processing. Nineteen healthy young adults participated in a visual oddball task using happy faces as standard stimuli (80%) and angry faces as deviant stimuli (20%) selected from the Karolinska Directed Emotional Faces database. This paradigm was passive because participants simultaneously performed an auditory counting task. EEG was recorded using a 64-channel system. Global field power (GFP) was used to identify major event-related potential (ERP) components, followed by permutation-based statistics and distributed source reconstruction with eLORETA. Emotional state was assessed before and after the experiment using the Differential Emotions Scale. ERP components were identified at approximately 116 ms (P1), 204 ms (N170), 308 ms (P3), and 424 ms (N400). Source reconstruction demonstrated the involvement of occipital, parietal, and fronto-temporal regions during deviant stimulus processing. Participants exhibited a significant reduction in negative and anxiety-related emotions following the task. The emotional oddball paradigm under concurrent cognitive load elicited sequential ERP components reflecting early sensory processing and later attentional evaluation. Emotional deviance detection engaged both occipito-temporal and fronto-parietal networks. The observed association between executive engagement and emotional change supports the potential utility of EEG-based markers in the objective assessment of emotional processing.