Investigating effect chains from cognitive and noise-induced short-term stress build-up to restoration in an urban or nature setting using 360° VR

Population growth and increasing urbanization leads to growing exposure to traffic noise and a decline in accessible green spaces that could promote restoration from noise-induced stress. The objective of this virtual reality laboratory study was to investigate the effect chains of noise and cognitive demand on the build-up of short-term stress, and subsequent restoration in either a natural green or urban built quiet space. Participants were first exposed to road traffic noise of different sound pressure levels (L_Aeq of 35, 55, or 75 dB), being randomly assigned to passive listening (low cognitive demand) or concurrently performing cognitively demanding tasks (high demand). The stress phase revealed higher levels of perceived stress as well as tonic skin conductance for the high demand over the low demand group, independent of noise exposure. Increasing noise exposure was associated with elevated noise annoyance ratings and lower self-assessed wellbeing. In the subsequent restoration phase, all measures of perceived restoration indicated a clear advantage for green over non-green spaces. Further, participants from the high-demand group who were immersed in the green restorative space displayed significantly lower skin conductance levels than those in the urban built spaces. The findings suggest that exposure to natural green spaces is beneficial for psychological as well as physiological restoration from short-term stress induced by noise and cognitive demand. Our study underlines the important beneficial role of urban green spaces, particularly in densely populated, noisy urban environments.