Posts Tagged ‘executive function’
Nature philosopher Henry David Thoreau knew the value of time spent outside. “An early-morning walk is a blessing for the whole day,” he wrote. Although this thought has been used to generate enthusiasm for exercise and weight loss, Thoreau meant a walk in a natural setting, not on a treadmill or around a track – or even, apparently, through an urban area.
Over a century later, science has finally caught up with Thoreau. A study headed by Stephen Kaplan at University of Michigan’s Psychology Department, “The Restorative Benefits of Interacting with Nature,” offers some clinical evidence that walking in nature is more than good for the circulatory system and the waistline: it’s good for the mind.
How so? The brain (specifically the pre-frontal cortex) constantly assesses our surroundings. It’s a reflex designed to keep us from harm. The pre-frontal cortex also performs a process called executive function, essentially defined as the brain’s ability to plan our actions based on incoming stimuli. Is it necessary to run away from that car that just blew its horn? To duck or turn away from the exhaust from the bus? Is it okay to just keep going and ignore that dog barking at us from the parked car? In an urban or electronically “plugged-in” environment, the prefrontal cortex is constantly stimulated, and the brain has to work hard in order to sort out the stimuli. When we walk in the city, we have to avoid fellow pedestrians, dodge cars, pay attention to traffic signals, and so on; the brain, calling on our memory, also tunes out ambient city noise, buses going by, etc., since they’re (in general) not harmful threats. Hence, a walk in the city is good for the muscles, and may alleviate stress, but the brain really doesn’t get a break – it’s constantly being bombarded with the sights and sounds of potential danger.
Consider the alternative. While walk in a natural setting may have interesting sights and sounds such as a soaring eagle or magnificent view, psychological research has suggested that these stimuli are perceived as a whole. For example, the prefrontal cortex receives a gorgeous sunrise as a stimulus, but it doesn’t require much of an executive decision. There is no reason to act upon it (except to maybe take a picture.) The brain doesn’t have to process it any further. According to this research, a walk in the woods is like a vacation for the mind: it allows the prefrontal cortex to relax a bit, restore itself, and then be able to function better when we do go into a more exciting environment.
It’s interesting to note that giving the pre-frontal cortex a rest may be even more beneficial for children. As I mentioned in an earlier article, executive function allows for kids to “self-regulate,” essentially to exert self-control and discipline, and to respond appropriately to their surroundings and peers. When my kids seem to be better behaved after a nice long hike, I used to think it was because I wore them out. Maybe it’s because I gave their brains a break.