Handedness modulates emotion cognition interactions as revealed by ERPs and alpha oscillations

Emotion and cognition are interrelated lateralized brain functions, yet their interaction may vary with handedness due to differences in hemispheric specialization. We investigate how handedness modulates emotion-cognition interactions using electroencephalography/event-related potentials (EEG/ERPs) in healthy young adults. Participants completed a hemi-field emotional oddball task, where visually identical circles appeared in either the left or right visual field, and fearful or neutral distractors were shown centrally. Circles on the block-specific "frequent" side served as standard stimuli, while those on the opposite side were spatially defined oddball targets. Neural activity was recorded using a 256-channel EEG system. Fearful distractors elicited greater ERP amplitudes (P100, P300, LPP) and increased alpha oscillations, reflecting heightened emotional processing and attentional engagement. Right-handers showed more adaptive engagement, with post-fear alpha suppression and enhanced P300 and LPP amplitudes to targets in right parietal sites, indicating efficient attentional reallocation via right hemisphere mechanisms. In contrast, left-handers exhibited bilateral ERP responses to fear and sustained bilateral alpha activity during subsequent target processing, suggesting greater reliance on inhibitory control to manage emotional carryover, but with reduced attentional reengagement. These findings reveal distinct lateralized patterns of emotion-attention interactions based on handedness, offering new insights into brain asymmetry and informing personalized educational and clinical approaches.