Electrocortical correlates of facial expression processing: Assessing associations with stress, loneliness and...

Little is known about how stress and loneliness affect behavioural and neural correlates of face emotion recognition, particularly when assessed using event-related potentials (ERPs). Moreover, the influence of sex/menstrual cycle phase and sex hormones on these relations has not been explored, representing a notable literature gap.

Participants (N = 78, 50F) completed a face emotion recognition task while undergoing electroencephalographic (EEG) recordings. The Perceived Stress Scale (PSS) and UCLA Loneliness Scales (ULS) were completed, and salivary cortisol, estradiol, progesterone and testosterone were collected. Face-sensitive (N170, VPP, EPN), sensory-processing (P2, N1), and cognitive-control/evaluation-related ERPs (N2 LPP) were assessed reflecting the various stages of facial expression processing.

Higher loneliness was linked with increased cortisol levels. Higher P2 amplitudes and greater late LPPs existed in those with low stress; those with low stress also had smaller VPP amplitudes, particularly to fear and disgust faces. Low loneliness was associated with longer N1 latencies to disgust. Perceived stress and loneliness influenced performance depending on menstrual cycle phases in females. Males vs. females with higher stress showed larger N170 amplitudes to fear and disgust; females in the follicular vs. luteal phase with higher loneliness had enhanced LPPs to negative emotions.

Complex interactions between loneliness, stress and sex-related factors in emotion recognition exist. Particularly, there appears to be increased sensitivity to negative facial expressions shaped by stress, loneliness and menstrual cycle phase. These insights advance integrative models of emotion processing by considering psychosocial and sex-related factors within a more holistic approach beyond isolated factors.