Psychological and physiological effects of soundscapes: A systematic review of 25 experiments in the English and Chinese literature

The aim of this systematic review was to conduct a comprehensive and rigorous investigation of both psychological and physiological responses to, and audio-visual interactions with, soundscapes to present an overview of the current status and to provide suggestions for future research. Our literature search focused on empirical and quantitative studies of journal articles and gray literature in English and Chinese. This systematic review excluded literature related to pure music, religious sounds, humanistic sounds, historical sounds, medical research, and differences in materials used. The Joanna Briggs Institute's Checklist for Randomized Controlled Trials was used to assess the risk of bias in the included studies. Twenty-five studies were included, involving 1950 participants. The major findings of this systematic review were that: (1) there were significant associations between the psychological and physiological responses; (2) the audio-visual interaction affected the psychological and physiological responses; and (3) because of the high risk of bias of the included studies, interpretation of their findings should be cautious. Nevertheless, given that this systematic review has a higher level of evidence than a single study and the synthesized evidence identified in this review is aligned with the results of other studies, the studies reviewed herein together provide consistent evidence. Replications are important in empirical research to build trustworthy results. Future research should focus on the psychological responses of pleasantness, preference, tranquility, the eight semantic dimensions (ISO 12913-2:2018), and the 11 pairs of adjectives describing the soundscape (Ba et al., 2023) and the physiological responses of heart rate variability and salivary, and follow the CONSORT guidelines to improve the research quality. An integration of sensory modalities, environmental factors, contextual indicators, temporal data, demographic variables, socio-cultural factors, and psychological and physiological responses may provide deeper insights into how people experience and understand the acoustic environment in context.