Physical and mental exercises protect memory by rewiring the brain

Physical and mental exercises protect memory by rewiring the brain

For the first time, researchers have revealed that progressive resistance exercise (high intensity strength training) and computerized cognitive training (brain training) produce unique changes in the brain that help explain their therapeutic value.

Prior to these findings, published in Molecular Psychiatry, researchers hadn’t pinpointed what changes in brain biology – collectively known as neuroplasticity – could explain their cognitive effectiveness.

“What we have shown for the first time is that physical and cognitive exercise led to different kinds of benefits in cognition in older people, and these are based upon distinct neurobiological mechanisms,” said Associate Professor Michael Valenzuela, from the University of Sydney’s Brain and Mind Centre.

“The trial shows that resistance and cognitive training can be used to target different brain mechanisms – changes that together can help combat the effects of aging and Alzheimer’s disease.”

The study was a randomized control trial of 100 non-depressed older individuals (average age 70 years) who were at high risk of future dementia.

Individuals were randomized (like the toss of a coin) to one of four training groups in which they completed two types of supervised center-based training per session (physical and cognitive), twice per week, for a total of 6 months. Each session lasted 90 minutes and comprised either:

  • Resistance exercise and computerized cognitive training
  • Resistance exercise and a placebo computerized training (watching nature videos)
  • Brain training and a placebo exercise program (seated stretching/calisthenics)
  • Placebo physical exercise and placebo cognitive training

The researchers found that resistance exercise led to structural brain plasticity, specifically, a thickening of grey matter in the ‘posterior cingulate’ cortex, a key integrating part of the brain that is affected early in Alzheimer’s disease.

By contrast, the control group underwent a small shrinkage in posterior cingulate grey matter.

Importantly, this plastic change was linked to global cognitive benefits as measured by the Alzheimer’s disease Assessment Scale-Cognitive scale.

This is one of the most commonly used scales in dementia drug trials and differentiates between normal cognition, mild impairment and dementia.

In parallel, the researchers found that their brain training program strengthened connectivity between the brain’s memory center (the hippocampus) and the frontal lobe – changes that specifically protected against memory decline as seen in the control group.

“Given the alarming predictions for dementia over the coming decades, this information should help design more effective dementia prevention strategies as well as contribute to their clinical and community implementation.”

Follow Knowridge Science Report on Facebook and Twitter

News source: University of Sydney. The content is edited for length and style purposes.
Figure legend: This image is for illustrative purposes only.