Neurophysiological correlates, linguistic richness and subjective components in stressful interactions during discourse production

This study investigates neurophysiological, behavioural, and linguistic responses during stressful discourse production. Thirty-six participants completed a Social Stress Test (SST) with five speeches under evaluative feedback conditions ranging from friendly to hostile. Linguistic richness (Lr) was measured via Types-Tokens Ratio (TTR), alongside response times (RTs) and electroencephalographic (EEG) activity (Delta, Theta, Alpha, Beta, and Gamma bands). RTs decreased significantly across tasks, reflecting habituation, while TTR increased under hostile feedback, indicating heightened linguistic adaptability. EEG analyses revealed task-specific neural patterns: Delta power rose during introspective tasks, while Beta activity increased in parieto-occipital regions during hostile feedback, reflecting attentional and visual processing demands. Mindfulness and emotional regulation were associated with better TTR and adaptive neural responses, suggesting resilience against social stress. These findings contribute to understanding the interplay between linguistic, emotional, and neurophysiological processes under social stress and support applications in neurofeedback and mindfulness training to enhance communication under pressure.