Exercise Benefits Dentate Gyrus Function: Bridging from Animal Models to Human High-Resolution Functional MRI of Pattern Separation.

Animal studies have demonstrated that physical exercise enhances neural plasticity, particularly in the hippocampal dentate gyrus (DG), and improves learning and memory. Notably, these effects are more pronounced with light-intensity exercise compared to higher-intensity exercise. Recent advancements have enabled the investigation of hippocampal memory in humans, especially DG-dependent pattern separation, providing a bridge between animal and human research. In this chapter, we outline the methodological approaches for assessing hippocampal pattern separation using mnemonic discrimination tasks and high-resolution MRI, and we review key studies examining the effects of aerobic exercise on human DG function. Evidence from cross-sectional, acute, and chronic exercise intervention studies supports the positive impact of exercise and physical activity, with some findings aligning with the exercise hormesis observed in animals. However, further research is needed to determine the optimal exercise conditions for enhancing hippocampal memory and to elucidate the underlying neural mechanisms.