A new study led by the University of Maryland School of Public Health revealed that walking interventions could improve the neural connectivity in older adults, potentially reducing the risk of mild cognitive impairment (MCI) or Alzheimer's disease.
The study, published in the Journal of Alzheimer's Disease, showed that walking for 30 minutes for four times a week can increase the neural connectivity between the brain's posterior cingulate cortex (PCC)/precuneus region and other brain regions of patients diagnosed with MCI.
"The brain's posterior cingulate cortex (PCC)/precuneus region is a hub of neuronal networks which integrates and disperses signals," said Dr. J. Carson Smith, director of the Exercise for Brain Health Laboratory and senior author of the study, in a press release. "We know that a loss of connectivity to this hub is associated with memory loss and amyloid accumulation, both signs of MCI and Alzheimer's."
For the study, the researchers recruited a total of 32 participants aged 60 to 88 years old. Half of the participants were diagnosed with MCI, while the remaining 16 were healthy. All the participants were asked to participate in an exercise intervention that included 30-minutes walk, four times a week for three months.
The participants also underwent fMRI brain scans before and after the exercise intervention. The researchers used the brain scans to access the functional connectivity between multiple brain regions and the PCC/precuneus.
The researchers observed that participants from both groups showed improved ability to remember a list of words. However, only the group diagnosed with MCI showed increased connectivity to the PCC/precuneus hub, which was evident in 10 regions spanning the frontal, parietal, temporal and insular lobes and the cerebellum.
It is still unclear whether the positive effects of exercise intervention could delay further cognitive decline in patients with MCI. However, the study's findings suggest that exercise training could have protective effects that can be realized by the brain re-establishing communication and connections among the brain's default mode network. These re-establishments could potentially increase the capacity of the brain to compensate for the neural pathology associated with Alzheimer's disease.