New research suggests that regular walks can change brain structure – a team of scientists noticed changes in the prefrontal cortex, which improved participant concentration and memory
COVID-19 lent new meaning to talking a walk. In the UK, walks became limited to one a day at the height of lockdown. While practically unenforceable, the walk became immensely precious, a daily jewel, to adorn the stasis of being home-bound.
For people in non desk-based jobs, walking remained a regular part of their commute – no different, just a moment of migration at some point between home and a dangerous, potentially infected environment.
Even before the pandemic, the suggestion of taking a walk to feel better was a common refrain. Walking has long been a way to think, problem-solve, and clear the brain of chaotic, tangled ideas.
Now, a study by the Max Planck Institute for Human Development presents evidence that suggests taking regular walks actually changes brain structure.
‘Brain structure and mood improve’, says lead author
Simone Kühn, head of the Lise Meitner Group for Environmental Neuroscience at the Max Planck Institute for Human Development and lead author of the study, said: “Our results show that our brain structure and mood improve when we spend time outdoors.
“This most likely also affects concentration, working memory, and the psyche as a whole. We are investigating this in an ongoing study. The subjects are asked to also solve cognitively challenging tasks and wear numerous sensors that measure the amount of light they are exposed to during the day, among other environmental indicators.”
Scientists saw changes in cerebral cortex gray matter
The team found that there was a noticeable difference in gray matter, for the right dorsolateral-prefrontal cortex – the superior (dorsal) and lateral part of the frontal lobe in the cerebral cortex.
This part of the brain is involved in the planning and regulation of actions, and also cognitive control. Cognitive control, also known as executive control, is the process through which goals or plans influence behaviour. The more walking participants did, the more likely they were to be able to plan and control their own behaviour.
Scientists also link psychiatric disorders to a reduction in gray matter, meaning that more gray matter could play a role in protection against later mental health issues.
The study sample was small, so what next?
These neuroscience findings are based on six months of observing six middle-aged city dwellers, who provided 280 MRI scans of their brains. The six were also asked about their fluid intake, consumption of caffeinated beverages, the amount of time spent outside, and physical activity, in order to see if these factors altered the association between time spent outside and the brain.
In order to be able to sift out seasonal differences, the amount of sunshine in the study period was also observed.
The team will now look at the differences in brain structure between city-dwellers in an urban space, and individuals who live in much greener spaces. The changes in brain structure both open up new therapies for mental health and elaborate on existing ideas about how surroundings can influence a persons’ life.
Anna Mascherek, post-doctoral fellow in the Department of Psychiatry and Psychotherapy of the Medical Center Hamburg-Eppendorf (UKE) and co-author of the study, said: “These findings provide neuroscientific support for the treatment of mental disorders. Doctors could prescribe a walk in the fresh air as part of the therapy – similar to what is customary for health cures.”
