Viewing Nature Reduces Stress- But only if it is real

Numerous studies have shown the emotional and physiological benefits of direct visual and physical access to nature. Watching tropical fish swim in a tank or viewing a scene of natural beauty can provide significant stress reduction rewards for many people. Patients in a bed by a window that provides an attractive vista of nature seem to fare better than roommates who have only a wall or curtain to look at. Gardens located in healthcare settings also offer patients, visitors, and staff the opportunity for direct interaction with the restorative, calming effects of nature. A few decades ago, my good friend, Norman Cousins, others, and I were involved in a project to demonstrate how implementing these practices could reduce anxiety and pain medication requirements hospitalized patients and even improve staff productivity. At the University of Texas M.D. Anderson Cancer Center in Houston, an 800-gallon aquarium was implanted into a lobby wall so patients, visitors, and hospital personnel could view a variety of fish flashing their brilliant scales as they flitted through the tank.

Judging from their popularity, videotapes of nature or tropical fish that are often accompanied by a soothing soundtrack seem to provide similar benefits. However, a recent study suggests otherwise. Researchers recruited 90 college students to participate in an experiment in which they worked on four mental tasks while sitting at a desk in an office. With 30 of the students, the desk faced a window overlooking a campus scene that included a large fountain and trees. For the second group of 30, the window was replaced with a high-definition plasma screen that showed the same nature scene in real-time. For the remaining 30 students, curtains covered the plasma screen and the desk faced a blank wall.

Each participant was hooked up to a heart rate monitor and told to wait for five minutes while the researcher stepped out of sight. A concealed wall camera was synchronized with the heart monitor and tracked participants’ eye movements. At the end of the waiting period, the researcher returned explained the first task and stepped out of sight. This was repeated for the remaining three tasks and then the subject was again told to wait for five minutes. Heart recovery rate was based on how quickly each participant’s heart rate dropped in the 60 seconds after being told to wait or to have one of the tasks explained. Each person’s performance was tallied on the basis of six measurements, once after every task and the two waiting periods. Low-level stress was created by having to deal with another person in a social situation and the anticipation or performance anxiety each might have experienced to do well on the four tasks.

The researchers found that the glass window reduced low-level stress as assessed by heart rate recovery and that the plasma window was no more restorative than a blank wall. Moreover, when participants spent more time looking through the glass window, their heart rate tended to decrease more rapidly. However, this was not the case with the plasma screen, even though the students looked at this just as often. The lead author was surprised, noting, I thought the plasma screen would come somewhere between the glass window and the blank wall. . . .This study is important because it shows the importance of nature in human lives and at least one limitation of technological nature. In the years ahead, technological nature will get more sophisticated and compelling. But if it continues to replace our interaction with actual nature, it will come at a cost. To thrive as a species, we still need to interact with nature by encountering an animal in the wild, walking along the ocean’s edge or sleeping under the enormity of the night sky.”

Nevertheless, alteration in heart rate is only one of many ways to assess stress. Several studies have demonstrated the benefits of various stress reduction videotapes based on other objective criteria as well as self-report.

Reference: Kahn, PH, Friedman B, Gill B, et al. A plasma display window?—The shifting baseline problem in a technologically mediated natural world. Journal of Environmental Psychology, 2008; 28: 192-199.