# Physical activity simultaneously improves working memory and ripple-spindle coupling

## TL;DR

Short bursts of physical activity improve working memory by enhancing brain wave coordination in memory-related regions.

## Contribution

This study shows physical activity boosts working memory via ripple-spindle coupling in the brain.

## Key findings

- Physical activity improves working memory performance.
- Ripple activity increases with memory load after physical activity.
- Ripple to awake-spindle coupling strengthens following physical activity.

## Abstract

Ripples, representing the compressed reactivation of environmental information, provide a mechanism for retaining memory information in chronological order and are also crucial for working memory (WM) during wakefulness. Brief sessions of physical activity (PA) are proposed to boost WM. In concurrent EEG/MEG sessions, we investigated the role of PA in WM performance and high-frequency-ripple to wake spindle coupling. Ripples, identified in MEG sensors covering the medial temporal lobe (MTL) region, predicted individual WM performance. Ripples were locked to robust oscillatory patterns in the EEG defined spindle band. Wake spindle activity and ripples decrease during initial stimulus presentation and rebound after 1 sec. Behaviorally, PA enhanced WM performance. Neurophysiologically, PA scaled the ripple rate with the number of items to be kept in WM and strengthened the coupling between ripple events and wake spindle events. These findings reveal that PA modulates WM by coordinating ripple-spindle interaction.

After short-term Physical activity (PA), working memory (WM) performance improved. Ripple activity increased with memory load, and ripple to awake-spindle coupling strengthened, suggesting PA boosts WM via hippocampal-thalamocortical dynamics.