Short-Form Mindfulness Training Protects Against Working Memory Degradation over High-Demand Intervals

Periods of persistent and intensive demands may compromise working memory (WM) and increase susceptibility to distraction. We investigated if mindfulness training (MT) may mitigate these deleterious effects and promote cognitive resilience in military cohorts enduring a high-demand interval of military training. To better understand which aspects of MT programs are most beneficial, three military cohorts were examined. Two groups received 8-h variants of an MT course, Mindfulness-based Mind Fitness Training (MMFT)(R), with one group emphasizing in-class training exercises (M8T, n = 40) and the other emphasizing didactic content (M8D, n = 40). A third group received no training (NTC, n = 46). Performance on a delayed-recognition WM task that varied mnemonic load (1 vs. 2 items) and delay-spanning valenced distraction (negative vs. neutral images) was measured before (T1) and after (T2) an 8-week interval. Overall, task accuracy (% correct) was greater on low- vs. high-load trials, as well as trials with neutral vs. negative distraction. Task accuracy did not change over time in a civilian cohort (N = 22). Yet, it declined from T1 to T2 in the military cohorts, with the greatest degradation in NTC, followed by M8D, and near stable performance from T1 to T2 in M8T. This time by group effect significantly varied with load, but not with distracter valence. While NTC's performance degraded over time for both low- and high-load trials, M8D's performance degraded only for high load, and M8T did not show performance degradation for either load condition. These results suggest that MT may protect against WM degradation over high-demand intervals, with training-focused MT programs offering the greatest benefits for maintaining performance in high-load conditions.