Psychophysiological responses to traffic noises in urban green spaces

Abstract

The present study aims to explore the psychophysiological impact of different traffic sounds in urban green spaces. In the experiment, 30 subjects were recruited and exposed to different traffic sounds in the virtual reality (VR) scene. The road traffic sound and three railway sounds (con-ventional train, high-speed train, and tram) with three sound levels (45, 55, and 65 dB) were used as the acoustic stimuli. Physiological responses, electrodermal activity (EDA) and heart rate (HR) were monitored throughout the experiment. Psychological evaluations under each acoustic stimuli were also measured using scales within the VR system. The results showed that both the psychological and the physiological responses were significantly affected by the traffic sounds. As for psychological responses, considerable adverse effects of traffic sounds were observed, which constantly increased with the increase of the sound level. The peak sound level was found to have a better performance than the equivalent sound level in the assessment of the psycho-logical impact of traffic sounds. As for the physiological responses, significant effects of both the acoustic factors (sound type and sound level) and the non-acoustic factors (gender and exposure time) were observed. The physiological effect of high-speed train noise was significantly differ-ent from those of the other three traffic noises. The relationship between sound level and physi-ological parameters varied among different sound groups. The variation of sound level could hardly affect the participants' HR and EDA when exposed to the road traffic noise. On the con-trary, the physiological responses were significantly affected by the sound level of rail traffic noise. By a correlation analysis, no linear correlation between the psychological evaluations and HR was found.