High Trait Anxiety Attenuates EML Amplitude Following Uncertainty Resolution: ERP Evidence of Impaired Emotional Disengagement.

Background: Trait anxiety reflects a stable predisposition to experience heightened anxiety across contexts. While its role in amplifying emotional responses during threat anticipation is well established, its influence after the resolution of uncertainty remains underexplored. Purpose: This study examined whether individuals with high trait anxiety exhibit impaired neural disengagement following uncertainty resolution, compared with individuals with low trait anxiety. Emotional disengagement was operationalized using the Extrication from Mental Load (EML) component as a neurophysiological index. Methods: Using a between-subjects extreme-group design, twenty-two university students were selected from the upper and lower tails of the State-Trait Anxiety Inventory-Trait (STAI-T) distribution and assigned to high and low trait anxiety groups (n = 11 per group). Participants completed a probabilistic two-level contingent negative variation (CNV) paradigm designed to manipulate uncertainty resolution. Neural disengagement was indexed by the peak-to-peak amplitude and latency of the EML component following uncertainty resolution. Results: Compared with the low trait anxiety group, the high trait anxiety group exhibited significantly reduced EML peak-to-peak amplitudes, particularly over right frontal and midline parietal regions. No significant group difference was observed in EML peak latency. Conclusion: These findings indicate that trait anxiety primarily modulates the magnitude, rather than the temporal onset, of neural disengagement processes following uncertainty resolution, suggesting reduced efficiency of post-threat neural disengagement in individuals with high trait anxiety.