Differential effects of anxiety levels on dorsolateral prefrontal cortex-mediated emotional working memory

Abstract

Emotional working memory (WM) involves retaining and processing emotionally charged information, integrating emotions into cognitive tasks like decision-making and attention management. While anxiety affects dorsolateral prefrontal cortex (dlPFC) activity, research on how different anxiety levels impact WM remains inconclusive. To investigate this, participants were divided into Mild and Moderate anxiety groups based on their Beck Anxiety Inventory scores. Their performance on 2-back emotional WM task was compared both behaviorally and neurologically. Functional near-infrared spectroscopy was used to measure oxyhemoglobin levels in the dlPFC. The results showed that both groups had similar performance, with no significant differences in correct responses to the spatial location of emotional face stimuli. This suggests that emotional stimuli do not affect WM performance between groups. However, imaging data revealed hemisphere-specific differences in oxyhemoglobin changes, with no significant difference between hemispheres. The Moderate anxiety group exhibited reduced oxyhemoglobin levels in the right dlPFC compared to Mild anxiety group, while no significant difference was observed in the left dlPFC. These findings indicate that the degree of anxiety in healthy individuals affects WM processes in the right dlPFC, although this differs slightly from findings comparing high and low anxiety scores in healthy or diagnosed anxiety participants. Notably, these differences did not impair WM performance when participants provided non-verbal responses. This suggests that moderate anxiety may alter the neural mechanisms underlying WM without affecting the output of non-verbal tasks. Further research is needed to understand how WM, with or without emotional components, varies between individuals with mild and moderate anxiety levels.