The relationship between emotional well-being and exposure to nature in adults: A systematic review

ABSTRACT Background. Mental health tends to be poorer with the global growth in urbanicity. Exploring the effects of nature exposure on mental health can guide urban planning to improve mental health. The aim of this study is to synthesize evidence on the effects of nature exposure on adults' emotional well-being and related changes in brain activity. Methods. Following PRISMA and PECOS guidelines, peer-reviewed literature published between 2014 and 2025 was searched in PsycINFO, CINAHL, Web of Science, Scopus, Medline, Embase, and Google Scholar. Results. Out of 3,557 studies, 22 met the inclusion criteria. Their quality was assessed using the GRADE approach, and risk of bias using NICE. A positive association between nature exposure and emotional well-being was observed, including improved mood, reduced fatigue, and both neurophysiological and psychological relaxation. These benefits were linked to changes in functional activity in the prefrontal cortex in the left and right hemispheres, and bilaterally. Stress and anxiety outcomes varied across type of nature exposure and were generally associated with activation in the ventral posterior cingulate cortex and left frontal lobe. Stress reduction was further linked to decreased functional activity in the supplementary motor area and increased activity in the prefrontal cortex, associated with greater emotional regulation of stress. Conclusions: Results show beneficial changes in emotional well-being and functional brain activity linked to nature exposure. However, variability in the type and duration of nature exposure, small samples and cross-sectional designs were observed. Future research is needed that includes follow-up assessments and compares the effects across exposure types, frequencies, durations, and population subgroups.