(NewsNation) — An eye-tracking experiment highlighted mental health benefits for city dwellers who look at nature, especially trees.

The study, published June 4 in the journal People and Nature, used eye-tracking technology to document the link between intentionally looking at natural greenery versus human-made or grey elements in urban areas.

Study participants walked outdoors for 45 minutes along a route that resembled a typical commute. Researchers measured their cognition, affect, anxiety and “perceived restorativeness” before and after the walk.

Their findings suggest that people who focused on greenery felt more restored and less anxious. Focus on trees was associated with some of the greatest benefits compared to other natural elements.

Previous research has pointed to nature’s therapeutic benefits, including improved attention, lower stress, better mood, reduced risk of psychiatric disorders and heightened levels of empathy and cooperation, according to the American Psychological Association.

The U.K.-based Mental Health Foundation also notes that humans’ relationship with nature is crucial in “supporting good mental health and preventing distress.”