A new study suggests that maintaining a regular running regimen throughout middle age can help prevent or slow memory loss associated with aging. The research, conducted by scientists from universities in the United States and Mexico, focused on the effects of long-term exercise on neurons formed during early adulthood. Published in the journal eNeuro, the study found that running promotes the survival of adult born neurons and their integration into a network relevant to memory maintenance during aging. Now let’s break down the study!
New Study Suggests Running Can Prevent Memory Decline
The researchers examined the brains of mice that had access to a running wheel and compared them to sedentary rodents. While the study used mice as subjects and employed the use of the rabies vaccine to trace brain connections over several months, the findings highlight the benefits of regular exercise for human brain health. According to Henriette van Praag, one of the study’s authors, “long-term exercise can significantly benefit the aging brain and potentially prevent memory function decline by increasing the survival of adult-born neurons and modifying their network”.
The Science Behind the Study
The study investigated the functional significance of new granule cells born during early adulthood in the aging brain, referred to as “old” new granule cells (OnGC). The researchers used a rabies-virus tracing system to label the presynaptic neurons connected to OnGC in control and long-term running mice. The mice were injected with a retrovirus to label proliferating neural progenitor cells that become new neurons, and after six to nine months of control or running conditions, they were injected with a rabies virus to trace the inputs to the old adult-born neurons.
The results showed that long-term running increased the survival of the starter cells (OnGC) by 3.54-fold, particularly in the dorsal dentate gyrus. Running also increased the number of presynaptic traced cells connected to the old adult-born neurons by 2.04-fold. However, the ratio of total traced cells to starter cells was reduced by long-term running, indicating sparse connectivity and nonoverlapping connections. This suggests that running enhances pattern separation ability and supports orthogonal coding of neuronal information in the dentate gyrus.
Overall, the study suggests that long-term running promotes the survival of old adult-born neurons and modifies their network connectivity, potentially improving pattern separation and memory function associated with adult neurogenesis.
The study emphasizes the importance of including exercise in daily life, particularly from early adulthood through middle age, to maintain memory function during aging. The authors suggest that long-term running may enhance pattern separation ability, which is closely linked to adult neurogenesis and is one of the first cognitive functions to decline with age. While the study doesn’t provide specific guidelines regarding the distance or duration of running, it highlights the significance of consistency in maintaining a daily exercise routine for optimal brain health.