Better cognitive efficiency is associated with increased experimental anxiety

Abstract

There is increased interest in the development of cognitive training targeting working memory (WM) to alleviate anxiety symptoms, but the effectiveness of such an approach is unclear. Improved understanding of the effect of cognitive training on anxiety may facilitate the development of more effective cognitive training treatment for anxiety disorders. This study uses an experimental approach to examine the interplay of WM and anxiety following WM training. Previous studies show that increased demand on WM reduces concurrent anxiety evoked by threat of shock (induced anxiety). However, improving WM pharmacologically or via exercise prevents this anxiolytic effect. Conceivably, improving WM frees up cognitive resources to process threat information, thereby increasing anxiety. The present study tested the hypothesis that practicing a high load WM (i.e., increased demand) task would improve WM, and thus, free cognitive resources to process threat of shock, resulting in more anxiety (i.e., greater startle) during a subsequent WM task. Participants were randomly assigned to two training groups. The active-training group (N = 20) was trained on a 1- (low load) & 3-back (high load) WM task, whereas the control-training group (N = 20) performed a 0-back WM task. The experimental phase, similar in both groups, consisted of a 1- & 3-back WM task performed during both threat of shock and safety. As predicted, active training improved WM accuracy and increased anxiety during the experimental 3-back WM task. Therefore, improving WM efficiency can increase anxiety, possibly by freeing WM resources to process threat information.

Trial registration: ClinicalTrials.gov NCT00026559.

Keywords: anxiety; cognitive control; startle blink; working memory.

FIGURE 1

Startle (eyeblink) magnitude in the control-training and active-training groups in the safe and threat conditions of the 1-back and 3-back WM loads. * indicates a significant increased (p < .01) from the safe to the threat condition (i.e., fear-potentiated startle). ^ indicates a significant decreased (p = .02) in fear-potentiated startle magnitude from the 1-back condition to the 3-back condition in the control-training group. ns indicates no significant difference in fear-potentiated startle magnitude between the 1-back and 3-back condition in the active-training group. Error bars are SEM