Towards an emotional 'stress test': a reliable, non-subjective cognitive measure of anxious responding

Abstract

Response to stress or external threats is a key factor in mood and anxiety disorder aetiology. Current measures of anxious responding to threats are limited because they largely rely on retrospective self-report. Objectively quantifying individual differences in threat response would be a valuable step towards improving our understanding of anxiety disorder vulnerability. Our goal is to therefore develop a reliable, objective, within-subject 'stress-test' of anxious responding. To this end, we examined threat-potentiated performance on an inhibitory control task from baseline to 2-4 weeks (n = 50) and again after 5-9 months (n = 22). We also describe single session data for a larger sample (n = 157) to provide better population-level estimates of task performance variance. Replicating previous findings, threat of shock improved distractor accuracy and slowed target reaction time on our task. Critically, both within-subject self-report measures of anxiety (ICC = 0.66) and threat-potentiated task performance (ICC = 0.58) showed clinically useful test-retest reliability. Threat-potentiated task performance may therefore hold promise as a non-subjective measure of individual anxious responding.

Figure 1

Violin plots (shaded area represents a histogram) (a). Accuracy to “no go” stimuli across threat and safe conditions. There was a main effect of condition (p = 0.04). (b) Delta accuracy (inset across three sessions). (c) Reaction time to “go” stimuli across threat and safe conditions. There was a main effect of condition (p = 0.012). (d) Delta reaction time (inset across 3 sessions). (e) Anxiety rating across threat and safe conditions. There was a main effect of condition (p < 0.05). (f) Delta anxiety ratings (inset across three conditions). (g) Shock level across baseline and follow up (main effect of session p = 0.003; inset shock level across three sessions). (h) Trait anxiety score across testing sessions (inset trait anxiety across three sessions). (i) Distribution of delta distractor accuracy scores on the SART in a large population (N = 157). Dotted line at zero demonstrates population as a whole shifted towards threat-potentiated accuracy.

Figure 2. Participants were instructed to press the space bar as quickly as possible for “go” stimuli and withhold responses to infrequent “no-go” stimuli.

(A) Participants received an unpredictable electric shock (independent of behavioural response) during the threat condition. (B) Participants were not at risk of shock during the safe condition.