Emotional Suppression Moderates the Relationship Between Autistic Traits and Physiological and Cognitive Responses to Acute Social Stress in a Healthy Adult Sample

Background:  

In the past decade, Autism has undergone a reconceptualization from a dichotomous, all-or-nothing clinical diagnosis to a dimensional classification including milder variants of the disorder, giving rise to interdisciplinary research on the broader autism phenotype (BAP). BAP examines subthreshold symptoms of ASD with the assumption that traits associated with the autistic spectrum are widely distributed and can be measured using self-administered instruments among adults with normal intelligence. Recently, we have demonstrated that the core features of AT, specifically social-communication deficits and restricted and repetitive behaviors, are associated with maladaptive emotion regulation strategies. Furthermore, it has been established that AT are related with dysfunctional stress coping; importantly, individuals with high levels of AT are more likely to have co-occurring stress-based disorders such as anxiety. To date, no studies have examined whether AT are associated with physiological responses to acute social stress and whether this link is moderated by emotion regulation. 

Objectives:

The aim of this study is twofold: 1) To explore whether AT are associated with higher levels of the stress hormone cortisol, higher heart rate, and lower levels of cognitive performance in response to acute social stress in lab. 2) To determine whether the link between AT and physiological responses to acute stress are moderated by emotional suppression. We hypothesized that individuals with high AT will have higher physiological responses to stress, and this association will be more pronounced with individuals high in emotional suppression (ES). 

Methods:  

Data was acquired from a community sample of 39 male adults between 19 and 54 years old (M=27.79, SD=8.24). Participants were exposed to a standardized psychosocial laboratory stressor, the Trier Social Stress Test (5-minute simulated job interview, followed by 5-minute mental arithmetic task). Heart rate was continuously tracked throughout the TSST and salivary cortisol was collected at eight 10-minute intervals, during baseline, adaptation, stress, and recovery phases. Number of mistakes on the mental arithmetic task was recorded as an indicator of cognitive performance. AT was measured using Autism Spectrum Quotient and ES was measured by the Emotion Regulation Questionnaire.

Results:  

AT was positively associated with cortisol and heart rate and negatively with the number of mistakes (rs > 0.37, ps < 0.03). Furthermore, emotional suppression significantly moderated the relationship between AT and salivary cortisol (β=1.72, t(35)=2.74, p<0.01) and the number of mistakes (β=1.44, t(35)=2.19, p=0.04). Simple slope analysis revealed that individuals high in AT and ES produced the highest levels of cortisol and made the most cognitive errors.

Conclusions:

The results of the current investigation extend the literature on AT by focusing on its physiological correlates for the first time. They also contribute to the growing volume of evidence that AT is associated with dysfunctional emotion regulation. Since dysfunctional emotion regulation and higher cortisol levels are linked to negative health outcomes, targeting maladaptive emotion regulation strategies of individuals high in AT through therapeutic interventions may be a way to preempt such outcomes.