Evidence shows that even a photo of nature positively effects the human mind.
Some amazing psychological and mental health benefits of human-nature contact are: reduced stress, better sleep, improved mental health, reduced depression, reduced anxiety, greater happiness, well-being, life satisfaction, reduced aggression, reduced ADHD symptoms, increased prosocial behavior and social connectedness. Attention Restoration Theory (ART) refers to nature’s ability to relieve mental fatigue.

Nature: Impacts on the Human Condition [Excerpt]