Memory under pressure: The impact of acute stress across different memory tasks

In the present study, we aimed to investigate how acute stress exerts its heterogeneous effects. Based on biophysical network models, we hypothesized that acute stress would improve occipital-mediated ultra-short-term and to a lesser degree affect occipital- and frontal-mediated short-term and working, and impairs hippocampal-mediated long-term memory processes and their respective behavioral measures. To test this, 111 healthy individuals (57 female) underwent both the Trier Social Stress Test (TSST) and a control test. Immediately afterward, participants' performance was measured in four memory tasks (Rapid Serial Visual Presentation, RSVP, Match-to-Sample, MTS, N-Back, NB and Free-Recall, FR tasks). TSST exposure seems to impair long-term memory (AC_FR; β = -1.50 ± 0.62; when free recall was tested approx. 80 minutes after initial encoding, immediately after the TSST), and working memory (AC_NB; β= -0.42 ± 0.20 %) but did not affect ultra-short-term (AC_RSVP; β = -0.03 ± 0.31 %) and short-term (AC_MTS; β=-0.18 ± 0.31 %) memory accuracies (ACs). Interestingly, TSST exposure increased the exploratory included measure of response times in MTS (RT_MTS; β =16.42 ± 7.18 msec) and impaired T1 detection in the RSVP (AC_T1; β=-0.48 ± 0.22 %) tasks. Contrary to the hypothesis, TSST exposure did not have the hypothesized effects on the memory processes. Instead, TSST exposure appeared to affect secondary behavioral indicators of motivation or task instruction adherence.