Mechanistic Underpinnings of Emotional Face Processing in Suicide Risk: Exploring the Moderating Effects of Cortisol...

Suicide has been linked to distinct impairments in emotional face processing. This magnetoencephalography (MEG) study used a multimodal design to address how cortisol dysregulation, often reported in individuals with suicidal thoughts and behaviors, affects emotional face processing.

The electrophysiological correlates of emotional face processing were investigated in 118 adults with varying suicide risk. Tonic cortisol levels and their moderating effects on face processing were analyzed. Participants performed an emotional evaluation task during MEG to categorize face stimuli. MEG data were source-localized in the gamma (30-58 Hz) frequency, and dynamic causal modeling (DCM) examined effective connectivity between regions implicated in face processing.

Individuals with a past suicide attempt (>1 year) showed blunted cortisol. Distinct gamma oscillation patterns emerged based on risk: at-risk groups showed higher gamma power in early visual cortex (EV) but lower power in superior frontal gyrus. Cortisol moderated EV gamma power in those with a recent suicide crisis, with higher EV gamma linked to lower cortisol levels. DCM revealed that at-risk groups exhibited increased effective connectivity from EV to amygdala (AMYG) during face processing.

A recent suicide crisis was characterized by disengaged higher-order processing of emotional faces despite heightened early sensory processing, which was moderated by tonic cortisol levels. Enhanced feedforward prediction errors from EV to AMYG suggest impaired top-down control in at-risk individuals.

Altered neural and hormonal responses to emotional cues highlight the potential for cortisol dysregulation and impaired top-down processing to serve as biomarkers of suicide risk. Incorporating these methods could eventually complement existing clinical suicide risk assessments, pointing to stress regulation or attentional retraining as practical adjuncts to suicide prevention.