Pilot Study on the Physio-psychological Effects of Botanical Gardens on the Prefrontal Cortex Activity in an Adult Male Group

Abstract

Background and objective: With modern lifestyles and the increasing severity of stress-related diseases, the availability and accessibility of the natural environment are critical. Botanical gardens in an urban area can provide opportunities for city dwellers to experience nature and enjoy stress-reducing activities. This study focused on the health-related effects of botanical gardens by investigating prefrontal cortical activity and changes in psychological states.Methods: The experiment was conducted in a national botanical garden located in the city of Sejong, and in an urban area of a contrasting city. Nine healthy adult males participated in the field experiment. Subjects were instructed to 'see and feel' the landscape in a sitting position for 10 minutes, both in the botanical garden and in the city center. The health effects of botanical gardens were verified using Near-Infrared Spectroscopy (NIRS), including changes in cerebral blood flow, and Profile of Mood State (POMS) and Perceived Restoration Scale (PRS).Results: Our findings showed that the oxyhemoglobin concentrations in the left prefrontal cortex were considerably lower in the botanical garden (-0.057 ± 0.003 µM) than in the city center (0.162 ± 0.002 µM, <i>p</i> < .001). Significantly positive psychological responses to the garden environment were found in the analysis of POMS and PRS, compared to the urban setting. These findings may indicate that a botanical garden can reduce negative psychological symptoms and physiological stress levels in adult males.Conclusion: Our study proves that botanical gardens have the environmental characteristics of restorative and therapeutic spaces. The findings indicated that urban gardens could be considered as health-improving environments by reducing the physio-psychological stress levels of urban dwellers.