Attention to social threat predicts diurnal cortisol dynamics during the high school transition.

Adolescence is a developmental period marked by significant social shifts accompanied by concurrent changes across biological, cognitive, and emotional domains. Within adolescence, the high school transition is a pivotal time for youth that is ripe with opportunities yet has the potential to disrupt functioning. An increasingly sophisticated understanding of health and developmental biology indicates that the hypothalamic-pituitary-adrenal (HPA) axis plays an important role in transducing social experiences into physiological changes that have long-term impacts on health and wellbeing. There is reason to believe that attentional biases to social threat could impact cortisol, a steroid hormone indexing activity of the HPA axis, during the high school transition. The present study examined associations between attentional biases to socially threatening stimuli, measured using the Affective Posner paradigm, and components of the diurnal cortisol rhythm among youth across the first two days of high school. Participants included 67 youth (N = 504 saliva samples) with a mean age of 12.86 years and a relatively equal split with regard to both sex assigned at birth and gender identity (54 % male; 54 % boys). Findings build upon and extend previous work by demonstrating that greater attentional engagement bias to socially threatening stimuli is associated with a pattern of greater diurnal HPA axis reactivity across the first two days of the high school transition, as evidenced by a steeper cortisol awakening response and a steeper diurnal cortisol slope. This work extends our understanding of the mechanisms through which stress relates to wellbeing in youth by embedding biological development in the life course. Clinically, this work has the potential to inform interventions to protect youth against the biological embedding of stress by identifying a theoretically driven, socio-contextually relevant risk factor to be attenuated - namely, attentional bias to threat.