The restorative effects of mental imagery of nature: A study on subjective and physiological responses

Exposure to natural environments, whether real or virtual, has been demonstrated to have restorative effects. However, it is unclear whether these effects depend on the meanings and associations that individuals attribute to different environments. This study explored the restorative effects of mental imagery of nature (i.e., pure top-down processing) following cognitive stress induction. Fifty students participated in a within-subject study where they imagined the contents of nature and urban words for 5 min each. Self-rated measures indicated a stronger sense of subjective restoration following nature imagery compared to urban imagery. The heart rate was slower, and heart rate variability was larger during nature imagery than during urban imagery, suggesting a greater degree of relaxation with nature imagery. Both tonic and phasic electrodermal activity was stronger during the mental imagery of nature than urban contents. This difference was driven by a higher preference for nature over urban words, indicating that imagery of nature was associated with stronger positive arousal than urban imagery. Notably, participants’ reported connection to nature moderated some of the physiological responses. In conclusion, top-down processes and individual meanings and associations play a significant role in the positive effects of nature exposure. The results also indirectly support the inclusion of nature imagery as a cost-effective component of therapeutic techniques aimed at promoting relaxation.