Roger S. Ulrich investigated the psychological benefits of natural environments. Ulrich and colleagues devised a psycho‐evolutionary theory in relation to natural environments which they called the Stress recovery theory.
Stress recovery, according to Ulrich, involves the recovery or restoration from excessively arousing states, both psychologically and physiologically (Ulrich et al, 1991). Stress recovery in this context is a part of the larger concept of restoration, which also encompasses factors such as recovery from under-stimulation and recovery from anxiety (Ulrich, 1993).
Ulrich's theory proposes that, after being in a stressful space, a biological and almost automatic preparedness initiates a response (Ulrich et al, 1991). This, in turn, motivates the individual to leave that environment in order to produce a positive emotional change, regulate the physiological effects of the stressful space, and recharge the energy that was exerted during the stress response Ulrich, 1993). Honold et al. (2016) re‐emphasise this idea, stating that positive affect experienced by nature adjusts an individual’s neurophysiological activation, which triggers nerve impulses that result in adaptive behaviours.
Ulrich also wrote a key paper in 1984 titled “View through a window may influence recovery from surgery” which studied the records of recovery after gall bladder surgery (between 1972 and 1981) to determine whether assignment to a room with a window view of a natural setting may have a restorative influence. It was noticed that those who were able to look out over natural scenes had shorter postoperative hospital stays and took fewer potent medicines than matched patients in similar rooms with windows facing a brick wall. [Ulrich, R.S., (1984). View Through a Window May Influence Recovery from Surgery. Science 224 420-421]