It's already been documented that time spent in nature can relieve psychological stress. However, what if you're somewhere where you can't access nature directly … somewhere such as a maximum security prison? Well, it turns out that even watching videos of nature can still make a big difference.

In a recent study led by psychologist Patricia H. Hasbach, inmates at Oregon's Snake River Correctional Institution were divided into two groups. For a year, half were given the opportunity to view nature videos during their scheduled indoor recreation time (three to four times per week), while half were not. These videos included images of forests, rivers, the ocean, aquariums, Earth as seen from space, and cloud fly-throughs.

Over the course of that one-year period, it was found that the inmates who watched the videos committed an average of 26 percent fewer violent infractions than their counterparts.

"Inmate surveys and case study interviews with inmates suggested that negative emotions and behaviors such as aggression, distress, irritability and nervousness were reduced following the viewing of videos and lasted for several hours post-viewing," said Hasbach.

Snake River prison staff are now using the videos as a means of intervention, when they suspect that a stressed inmate may be about to act out.