Does Green Improve Your Self-control?

Would you rather have a 100 dollars now or 150 dollars in 90 days’ time? This decision task is used in experimental psychology to measure people’s future discount rates. In other words, do people go for the smaller, immediate reward or wait for the larger reward in the future? The way people make these decisions says something about how much they value the future and this could have all sorts of implications for the way they lead their lives, for example, physical exercise, energy conservation, family planning, and even substance abuse. Research has found that drug addicts are more likely to take the smaller immediate reward when faced with these financial choices.

In a recent study, published in the Proceedings of the Royal Society a team of social psychologists and neuroscientists from the VU University Amsterdam (I was also part of this) used a discounting task to see if we could get people to value the future more by letting them appreciate the view of natural landscapes.¹

We first showed some participants pictures of nature and others pictures of urban scenes and then we gave them a number of these monetary decision tasks. Our main finding, replicated across two lab studies, was that people are more likely to opt for the longer-term reward after exposure to nature. In contrast, when people were exposed to urban scenes they became more impulsive, and many more of them preferred the 100 dollars now-option. On average, discount rates were as much as 13 percent lower in the “nature” group compared to the “urban” group.

Did this also work outside the lab? In a third study we let 43 participants, drawn from the general public, walk in either a natural environment or an urban environment in Amsterdam, the Netherlands, where we conducted our studies. After a five-minute walk they completed the discounting game. Again, the nature group opted for the larger future reward while the urban group chose the immediate, smaller reward more often. Additional results suggested that people reported to be in a better mood after being immersed in nature and that they liked the nature scenes more than the urban scenes. Yet a better mood could not explain the difference in discounting. Rather, we found that people were generally more forward looking after the nature walk.

Why is this finding important? Many of the problems that society faces today have to do with the typical human tendency to value the present more than the future. For instance, will I eat my cake now or exercise first and then eat it? Do I want to start a family now or wait until I have finished my education? Do I fill up my car with petrol or purchase an electrical car?

Our results show that giving people the opportunity to immerse themselves in a green environment may shift their time horizon from the here and now to the future. With the majority of the citizens of this planet now living in large, urban areas we must find clever ways to bring people in regular contact with nature. Particularly for our children regular outdoor experiences may be important to as they are more likely to discount the future.

Indeed, as an extension of our findings, we are currently investigating in the Netherlands the effects of green schoolyards on children’s social, cognitive, and emotional development. To be continued.....

Van der Wal, Schade, Krabbendam, & Van Vugt (2013). Do natural landscapes reducing future discounting in humans? Proceedings of the Royal Society B.