Hydrocortisone reduces emotional distracter interference in working memory

Abstract

Several studies have shown that stress and glucocorticoids can impair prefrontal-dependent working memory (WM) performance. WM is the ability to attend to the task at hand, and to maintain relevant information in mind during a delay while ignoring irrelevant stimuli. Here, it is investigated whether stress hormones impair WM by reducing the ability to suppress distracting, irrelevant neutral and emotional stimuli. Hydrocortisone (35 mg) (n=23) or placebo (n=21) was administered to young, healthy men, who performed a Sternberg WM task with neutral and emotional irrelevant distracters shown in the delay-phase of the task, between encoding and recognition of the relevant stimuli for WM. Contrary to expectations, enhanced WM performance with higher processing speed and a reduction of errors was found in the hydrocortisone group compared to placebo. Moreover, hydrocortisone significantly reduced the distraction by emotional stimuli. These findings show that cortisol effects on WM are not unambiguous and contrast with previous findings on the impairing effects of cortisol on WM. Dose-response studies could give more insight into the specific modulating effects of glucocorticoids on suppression of irrelevant emotional distraction.