Negative emotional cues improve free recall of positive and neutral words in unmedicated patients with major depressive disorder

Abstract

Individuals with major depressive disorder (MDD) exhibit attentional biases toward negative, mood-congruent stimuli while filtering out positive and neutral stimuli, resulting in memory biases to negative content. While attentional and memory biases in MDD have been extensively studied, the underlying mechanisms of these biases remain unclear. The current study investigates a novel model proposing that exposure to negative emotional cues triggers a transient "attentional window" in individuals with MDD, leading to heightened and deeper cognitive processing of any subsequent information, irrespective of its content. Forty-two unmedicated patients with MDD and no comorbid disorder and 41 healthy controls, completed six blocks of the emotional memory task, in which they were asked to watch a short video (negative, neutral, or positive valence) followed by a memory test on a list of neutral or positive valance words. Results indicated that participants with MDD, but not healthy controls, had better recall performance after a negative video compared to after neutral or positive videos, and that this effect occurred for both neutral and positive word-lists. These findings provide evidence that participants with MDD engage in deeper information processing following exposure to negative emotional stimuli. Potential clinical implications are discussed.

Keywords: Memory; attentional bias; depression; emotion; information processing.