Poor inhibition of personally-relevant facial expressions of sadness and anger predicts an elevated cortisol response following awakening six months later.

Failure to inhibit interference from distracting emotional stimuli may obstruct an individual's ability to regulate their behavioural and emotional responses to environmental stressors. Few studies have examined the longitudinal association between cognitive inhibition and regulation of the hypothalamic-pituitary-adrenal axis (HPA) in the natural environment. Seventy-nine healthy adults underwent two assessments 6 months apart. Participants' ability to suppress interference from distracting emotional stimuli was assessed using a negative affective priming task that included both generic and personally-relevant (i.e., participants' intimate partners) facial expressions of emotion. Poorer inhibition of personally-relevant sad and angry faces, but not generic stimuli, significantly predicted an increased cortisol awakening response (CAR) six months later. Moreover, poor inhibition of personally-relevant sad faces mediated the relation between chronic stress and an elevated CAR. Difficulties inhibiting personally-relevant emotional information may represent a key mechanism in understanding how environmental stress influences HPA functioning.