Alan C. Logan is a graduate of the Canadian College of Naturopathic Medicine and an invited faculty member at Harvard's School of Continuing Medical Education. His latest book, written in collaboration with Harvard Medical School physician Eva Selhub, explores the connection between nature and human health and happiness. Your Brain, On Nature: The science of nature's influence on your health, happiness and vitality was published by John Wiley Inc. in spring 2012.
Docs Talk: What happens to our brains "on nature"?
Dr. Logan: People commonly report that spending time in nature makes them feel better. A series of recent studies provides scientific support for this notion. Sophisticated brain-imaging techniques show that when healthy adults view nature scenes rich in vegetation, areas of the brain associated with emotional stability, empathy, and love are more active. These same pathways are activated when a person looks at pictures of a loved one. In contrast, viewing scenes of the built urban environment produced a significant increase in activity of the amygdala, an area of the brain associated with fear and stress. These findings support previous investigations showing that nature scenes can enhance brain-wave activity in ways that are similar to the benefits of meditation.
Docs Talk: How is day-to-day life preventing our brains from reaping those benefits?
Dr. Logan: There has been a shift away from nature-based recreation in favour of the ubiquitous screen. Even when individuals enter green space, they are often not really "there" in the mindful sense — texting, incoming messages, and eyes fixated upon Smartphones take the brain elsewhere. In many ways we are drowning in a sea of infotoxicity and entertainment media. Extracting ourselves from the information vortex is hard because "information", even of dubious quality, has a powerful physiological pull. To be clear, technology does wondrous things; it is not "bad". However, an overuse of gadgetry technology may be a key driver in the dilution of nature's benefits.
Docs Talk: What is science telling us about the connection between nature and healthy brains?
Dr. Logan: Let me highlight just a few of the important findings of late. Recent studies employing land-use data and satellite technology have reported that access to green space within a kilometre of one's residence is associated with improved mental health. Indeed, large population studies show that those with the least green space within one kilometre of home have a 25 per cent greater risk of depression and a 30 per cent higher risk of an anxiety disorder. Multiple studies from Japan show spending time in forests can lower stress, improve mental outlook, and lower levels of the stress hormone cortisol. Separate studies have shown similar cognitive-enhancing effects of short periods spent in natural settings. Spending just 20 minutes in vegetation-rich nature has been shown to improve vitality. Given that vitality is defined in psychological lexicon as emotional strength in the face of internal and external oppositions, and living life with enthusiasm and zest, the implications for personal and planetary health are enormous.
Docs Talk: What was the most surprising thing you discovered when researching this book?
Dr. Logan: I was struck by the sheer volume of published research on this topic. What started as a mere trickle of studies in the late 1970s has grown leaps and bounds in recent years. It is amazing how convincing the body of evidence has become that shows nature is a variable capable of influencing cognition and behaviour. To highlight one startling report published in the prestigious journal Lancet, a nationwide study in the United Kingdom found that green space is a profound equalizer of health inequalities. When low income was associated with little access to green space, there were significant health disparities between lower and higher socio-economic brackets. This gap narrowed when low-income individuals had access to green space near their residence. Green space helped to fill in the broad health divide between the affluent and the at-risk.
Docs Talk: What do you recommend people do to get their brains back on nature?
Dr. Logan: We need to push land-use planners and politicians to consistently prioritize access to green space as our cities continue to grow. I am hopeful that the recent scientific evaluations of nature's mental health benefits will help in this process.
As individuals, we can also take steps to foster a connection with nature, starting with getting out into green space in a mindful way. Paying attention to what you are experiencing in the current moment is the bridge between mere exposure to green space and its full rewards in the sphere of mental health. There are multiple ways in which people can make contact with nature in a mindful way — a 20-minute respite away from the office or classroom in an urban park, community or personal gardening, environmental volunteerism, interaction with animals and pets, and at the far end of the spectrum, adventure and so-called wilderness excursions. Obviously, this involves taking a techno-break and powering down the screen and Smartphone.
Docs Talk: What connection do you think your research has to helping us overcome the many environmental challenges we face?
Dr. Logan: There is every reason to be positive about the ability of renewed nature contact to feed greater concern for the environment. Multiple studies show that actual contact with nature, particularly in childhood, is one of the greatest predictors of pro-environmental attitudes. The good news is that, regardless of age, it is entirely possible to foster greater connectivity with nature by mindful contact with nature — and this enhanced connectivity manifests itself in more pronounced attitudes toward pro-environmental concerns. The missing link is awareness of the vitalizing effect of nature, but thankfully this is teachable. A more potent appreciation of the ability of nature to influence positive mental health can be a catalyst for broad change.