A new study conducted by researchers from Florida Atlantic University and CINVESTAV in Mexico City has shed light on the profound benefits of exercise for the aging brain. The study, published in the journal eNeuro, emphasizes the importance of maintaining physical activity throughout life, especially during middle age, to delay or prevent cognitive decline.
The researchers focused on the effects of long-term running on a network of new hippocampal neurons in young adult mice when they reached middle age. The study demonstrated that consistent exercise throughout middle age helps to keep old adult-born neurons wired, which could potentially prevent or delay age-related memory loss and neurodegeneration.
The hippocampus and adjacent cortices, crucial areas for learning and memory, are among the first structures in the brain to be affected by aging. Reduced hippocampal volume and degradation of synaptic connectivity between the hippocampus and (peri)-entorhinal cortex are associated with cognitive deficits. However, increasing evidence suggests that physical activity can counteract these structural and functional reductions in older adults.
The study utilized a unique approach involving the tagging of adult-born neurons with a fluorescent reporter vector and tracing their neural circuitry using a rabies virus-based technique. More than six months after labeling, the researchers analyzed the direct inputs to these adult-born neurons within the hippocampus and (sub)cortical areas in middle-aged mice.
The results revealed that long-term running significantly increased the number of adult-born neurons and enhanced the recruitment of presynaptic (sub)-cortical cells into their network. This finding suggests that exercise promotes the survival of adult-born neurons and modifies their neural circuitry, facilitating their participation in cognitive processes.
Furthermore, the study demonstrated that running not only rescued connectivity in brain areas essential for pattern separation and memory, such as the perirhinal and entorhinal cortex, but also increased the contribution of the entorhinal cortices to the network of old adult-born neurons.
The researchers propose that long-term exercise, starting from young adulthood and continuing into middle age, plays a vital role in maintaining memory function during aging. By increasing the survival and modifying the neural circuitry of adult-born neurons, exercise promotes their participation in cognitive processes and may delay age-related memory decline.
These findings highlight the relevance of incorporating regular exercise into our daily lives as a preventive measure against cognitive decline. As the population continues to age, understanding the benefits of physical activity for brain health becomes increasingly important for promoting healthy aging and improving overall quality of life.
This study provides compelling evidence that long-term running positively impacts memory function and neuronal connectivity in aging brains. By emphasizing the importance of exercise throughout life, especially during middle age, the research motivates individuals to engage in regular physical activity to preserve cognitive abilities as they age.