The Effects of Dance and Physical Training on Hippocampal Plasticity and Balance Capabilities in Seniors

Introduction

The human hippocampus (HC) plays a crucial role in memory, learning, and spatial navigation. With age, this structure undergoes normal and pathological degenerations, particularly in Alzheimer’s disease, leading to cognitive deficits. However, neuroplasticity is possible throughout life, and studies on physical activity in older adults show increases in hippocampal volume associated with improvements in aerobic fitness.

Dance is a promising activity for enhancing balance and brain structure in older adults. Unlike traditional fitness exercises, dance combines aerobic fitness, sensorimotor skills, and cognitive demands while presenting a low risk of injury. This study compares the effects of 18 months of dance and traditional physical training on the volumes of hippocampal subfields and balance capabilities.

Materials and Methods

Study Design and Subjects

This prospective longitudinal study compares the effects of dance and physical training on brain structure and motor performance in healthy seniors. Participants were randomly assigned to two groups: a dance group and a sports group, and underwent an 18-month program with three measurement points (before, after 6 months, and after 18 months).

Interventions

The dance program involved constantly changing choreographies focused on basic movements, rotations, shifts in center of gravity, single-leg positions, jumps, and various dance steps. The sports program included endurance, strength training, and flexibility exercises, performed on ergometers and through Nordic walking.

MRI Acquisition and Analysis

Magnetic resonance imaging (MRI) was acquired using a T1-weighted MPRAGE sequence. The volumes of hippocampal subfields were analyzed using the ANATOMY v.2.2.c toolbox from SPM, including the cornu ammonis (CA1-CA3), dentate gyrus (DG), and subiculum.

Postural Control

Postural control was assessed using the sensory organization test (SOT), providing information on the contribution of the visual, somatosensory, and vestibular systems to maintaining balance.

Statistical Analysis

Statistical analyses of hippocampal volumes and balance data were performed using SPSS. The effects of the intervention were tested using repeated measures ANOVA.

Results

Voxel-Based Morphometry with Hippocampal Mask

The repeated measures ANOVA revealed a significant interaction effect in the right hippocampus for the dance group, with a significant increase in volume after the intervention.

Measurements of Hippocampal Subfield Volumes

Dancers showed significant increases in several subfields of the left hippocampus (CA1, CA2, DG, subiculum) and in the right subiculum. Subjects in the sports group showed increases in CA1, CA2, and the left subiculum.

Postural Control

Dancers improved their use of the three sensory systems to maintain balance, unlike subjects in the sports group who only improved their use of the somatosensory and vestibular systems.

Correlation Analysis

No significant correlation was found between changes in hippocampal subfield volumes and balance improvements.

Discussion

The study shows that dance and physical training lead to increases in volume in several subfields of the hippocampus in older adults. Dance, in particular, appears to have a broader impact, likely due to its increased sensorimotor and cognitive demands. The correlation between balance improvements and changes in hippocampal volume remains to be further explored.

Conclusion

Dance represents a promising intervention to counter age-related declines in physical and mental capabilities, particularly by enhancing hippocampal volumes and balance capabilities in healthy seniors.

References

The original article from Frontiers in Human Neuroscience is available at