Acute Reactivity of Individuals With High and Low Levels of Ongoing Stress

Abstract

Objective: This study examined the impact of high levels of ongoing stress on responses to acute stress and cognitive challenge. We used a multimeasure approach to define the stress groups and to test multiple facets of the acute stress response, including mood, emotional arousal, autonomic responses, cognitive flexibility, and plasma metabolites.

Methods: Fifty healthy women designated as high stress (HS) based on the above threshold scores on a measure of perceived stress and current anxiety were compared with 50 women with low stress (LS) on both measures. Psychological, autonomic nervous system, and plasma metabolite assessments were obtained before, during, and after exposure to multiple tasks, including viewing affective pictures, performing stressful mental arithmetic, and figure-ground discrimination.

Results: The HS group showed a greater increase in negative affect when challenged with a laboratory stressor [b(SE) = 1.78, p < .001] and in response to neutral affective pictures (d = 0.41, p = .040); this same group showed overall less sympathetic arousal than the LS group during a mental arithmetic challenge [b(SE) = 0.28, p = .034]. The HS group had a higher plasma metabolite tryptophan/kynurenine ratio than the LS group at baseline, but this did not change with stress.

Conclusions: Increased negative psychological responses to both a psychological challenge and neutral affective pictures suggest that high-stress individuals process everyday challenging stimuli more negatively. Combined with the blunted ANS responses and potentially altered microbiome, this pattern suggests this high-stress responsive group, while currently healthy, may be at risk for biological stress-related morbidity in the immune, cardiovascular, or pain modulation systems.

Keywords: acute stress; autonomic nervous system; life stress; negative affect; plasma metabolites.