1216 GMT October 20, 2019
The findings focused on the visual cortex come as hopeful news for people with conditions including amblyopia (sometimes called lazy eye), traumatic brain injury, and more, the researchers say, scifeeds.com reported.
"We provide the first demonstration that moderate levels of physical activity enhance neuroplasticity in the visual cortex of adult humans," said Claudia Lunghi of the University of Pisa in Italy.
"By showing that moderate levels of physical activity can boost the plastic potential of the adult visual cortex, our results pave the way to the development of non-invasive therapeutic strategies exploiting the intrinsic brain plasticity in adult subjects," she added.
The plastic potential of the cerebral cortex is greatest early in life, when the developing brain is molded by experience. Brain plasticity is generally thought to decline with age. This decline in the brain's flexibility over time is especially pronounced in the sensory brain, which displays far less plasticity in adults than in younger people.
The researchers measured the residual plastic potential of the adult visual cortex in humans using a simple test of binocular rivalry. Most of the time, our eyes work together. But when people have one eye patched for a short period of time, the closed eye becomes stronger as the visual brain attempts to compensate for the lack of visual input. The strength of the resulting imbalance between the eyes is a measure of the brain's visual plasticity and can be tested by presenting each eye with incompatible images.
"We found that if, during the two hours of eye patching, the subject intermittently cycles, the perceptual effect of eye patching on binocular rivalry is stronger compared to a condition in which, during the two hours of patching, the subject watches a movie while sitting on a chair. That is, after physical activity, the eye that was patched is strongly potentiated, indicating increased levels of brain plasticity," Lunghi added.
Regardless of the mechanism, the findings suggest that exercise plays an important role in brain health and recovery. They come as especially good news for people with amblyopia, which is generally considered to be untreatable in adults.
"Our study suggests that physical activity, which is also beneficial for the general health of the patient, could be used to increase the efficiency of the treatment in adult patients," Lunghi said.