Your Brain and Nature: Restorative Effects of Exposure to Nature
Scientists have found that nature enhances human empathy and pleasure and reduces stress levels neurologically. Exposure to nature triggers the body’s parasympathetic nervous system. While the sympathetic nervous system is our “fight or flight” response which requires intense focus, adrenaline, and instant reaction, the parasympathetic nervous system is the “rest and digest” response which restores the body from its adrenalized state.
In modern life, our sympathetic nervous system is triggered constantly because sustained, directed attention is required to properly carry out everyday tasks from parking to checking email. The workday is filled with tasks that YOU are directly responsible for and require your attention to carry out. Not to mention the stresses of commuting, being in a workplace for eight hours each day, dealing with noise pollution both inside and outside, technological hiccups, and trouble shooting cause mental fatigue. Our parasympathetic nervous systems are necessary to restore from mental fatigue and physiological drain.
Nature triggers the parasympathetic nervous system by inducing a soft fascination—a passive attention that allows us to voluntarily pay attention to things that function completely independent of us. When taking a walk outside, we do not influence our surroundings and we are not immediately responsible for them. Plants and animals going about in their natural habitats immediately require nothing from us so we can involuntarily be fascinated which gives our bodies the opportunity it needs to restore our mental capacities for directed attention.
In the 1970’s researchers Rachel and Stephen Kaplan found that subjects’ directed attention capacity recovered at least in part after short walks in nature or even by simply looking at nature images. These subjects’ performance on cognitive tests also improved and they reported feeling happier.
Studies in the United States and in South Korea have recently found that when test subjects looked at nature pictures the regions of their brains that become more activated were the insula and the basal ganglia, which are associated with empathy and pleasure. Similarly, Rachel and Stephen Kaplan found that when subjects viewed images of nature before playing computer games they behaved less selfishly while playing them and appeared to be more creative.
Meanwhile, hemoglobin levels in the prefrontal cortex dropped after subjects viewed pictures of nature. The prefrontal cortex is the brain’s center for executive functioning. Hemoglobin levels dropping showed that this section was dimmed, allowing for attention to recover. Similar neurology has been observed in Tibetan monks’ brains.
With this in mind, city planners, architects, and interior designers are now creating human environments that allow active and passive access to green landscapes and the natural world. One idea is to design cities in a linear fashion—long and narrow instead of square or circular—to allow everyone living in urban areas easy access to the countryside.
- Robert Donahue