Few could argue against the therapeutic effects of nature or, failing that, even just a David Attenborough documentary. However, getting your fix of the natural world is not so easy if you're behind bars in the hyper-violent world of prison.

That’s why an ongoing project has been looking at whether nature films can help reduce levels of aggression and emotional stress among solitary confinement prisoners. The project, led by the University of Utah, has been going on for several years and their results have just been published in the journal Frontiers in Ecology and the Environment.

They followed inmates held in the solitary confinement block of Oregon’s Snake River prison for a year. The “Intensive Management Unit” is home to 48 men whose world consists of little more than gray concrete and fluorescent lights. The only relief is a tall-walled caged recreation yard where they exercise by themselves for 45 minutes around four times a week. As part of this experiment, they were also given access to a reel of 40 nature videos. The videos depicted a range of scenes, from forests and coral reefs, to satellite footage of Earth.

As part of this experiment, they were also given access to a reel of 40 nature videos. The videos depicted a range of scenes, from forests and coral reefs, to satellite footage of Earth.

So far, the results are quite remarkable.

Many members of staff were initially skeptical about the project, however, the dramatic drop in aggression within the prison is speaking for itself. Groups who viewed the nature videos were involved in 26 percent fewer violent incidents than those who didn’t. This means life for the prison guards has also been made considerably easier, along with making the inmate’s life more bearable.

“The nature project help’s me think clearer to know there is so much more beauty in this world than this prison,” one inmate wrote.

At least 43 percent of the inmates who watched the videos agreed or strongly agreed they found calmer and less irritable after watching the nature documentaries and over 80 percent stated nature videos made their time easier.

This echoes a study earlier this year that also found nature documentaries significantly boosts our happiness and reduces stress and anxiety. 

The study could also have benefits outside of the prison fences. The researchers believe these kinds of initiatives could improve the lives of millions of people who live in other nature-deprived environments, such as nursing facilities, homeless shelters, military barracks, etc.

The project has also just received a grant from NASA, in the hopes to bring in the mind-boggling imagery of outer space to cells of prisoners – something which inmates seem particularly interested in.

“NASA asked: What habitats do the inmates like best? I thought, being a forest person, that they’ll all say trees. None of them said trees and forests," lead author Nalini Nadkarni explained in a statement. "They all said, ‘Give us open habitat. Give us deserts and outer space.’”