Faculty Mentor: Genevieve Albouy (Health and Kinesiology, University of Utah)

Background

Prior research has established a connection between aerobic exercise and its benefits on cognitive function. Additionally, studies have highlighted the significance of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) in brain connectivity and synaptic plasticity, particularly within deep brain regions associated with memory and learning, such as the hippocampus and striatum. However, a gap exists in the literature regarding the specific neural mechanisms underlying exercise-induced cognitive improvements in these deep brain regions. Examining the potential influence of aerobic exercise on GABA levels in the hippocampus and striatum is essential due to GABA’s pivotal role in learning and memory processes. This study aims to explore the impact of exercise on GABA levels in these regions, offering insights into the neural processes contributing to exercise-induced enhancements in cognitive functions supported by these deep brain structures.

Methods

Ten participants took part in this study, and they were healthy males between the ages of 20-35. Participants were scheduled for three sessions that each occurred one week apart. The first session assessed level of fitness, and was used to calculate the participant’s VO2 max. The second and third sessions were counterbalanced across participants and consisted of a control intervention for one session and a high intensity interval training (HIIT) intervention for the other. Each participant was scanned with Magnetic Resonance Spectroscopy (MRS) to measure GABA levels in the striatum and hippocampus. Blood samples were also collected to measure the level of blood biomarker levels associated with neuroplasticity and GABA regulation. MRS and blood measurements were performed before and after the HIIT and control interventions.

Results

MRS data after the HIIT intervention showed that GABA levels stayed relatively stable within the striatum while they decreased in the hippocampus. After the control intervention, MRS data showed that GABA levels slightly decreased within the hippocampus and increased within the striatum. The blood biomarkers are in the process of being analyzed.

Conclusion

The preliminary findings indicate that acute exercise led to a reduction in inhibition in the hippocampus, while also counteracting the observed increase in inhibition seen in the striatum under the control condition. However, the study’s small sample size and focus on only healthy male participants limit its generalizability. Nonetheless, if the anticipated results are confirmed, it could pave the way for similar investigations involving diverse demographic groups and larger sample sizes. Moreover, expanding this research to include the aging population could offer valuable insights into strategies for addressing cognitive decline.

Bibliography

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