Effects of hearing diverse orthoptera sounds on human psychology

There is a growing interest in the health improvement functions of green spaces. Natural sounds have various effects on the human mind and body and this positive effect is a cultural service of the ecosystem; however, the mechanisms of these effects are poorly understood. This study investigated the psychological effects of diverse orthoptera calls on Japanese university people. Sixty-five participants were exposed to seven different sound sources, which comprised 1-4 different species, and then asked to answer questions on impressions and preferences. We compared the differences in preference scores according to species and number of species. Factor analysis was used to identify the common factors of impressions. Structural equation modeling was used to understand the influence of participants' attributes on their preferences. The results showed that as the number of species increased, the sound preference score increased. As a result of the factor analysis of the impressions, the factors Calm, Gorgeous, Musicality, and Deep were extracted; the factor scores of Gorgeous and Musicality increased as the number of species increased. Both, the inclusion of certain species and an increased diversity of species, increased the score. The combination of multiple species resulted in a favorable evaluation due to the harmonization of sounds and diversification of rhythms on the time axis. The results showed that the presence of diverse species of orthopteran calls has a positive effect on humans; orthopteran sounds are assumed to have psychological restorative effects. However, since the influence of the participants' attributes on preference was unclear in this result, further research is required to understand the effects of racial and cultural backgrounds, age, place of residence and personal attributes. Diverse orthopteran calls are an ecosystem service that contribute to the quality of the soundscape.

Automated summary

There is a growing interest in the health improvement functions of green spaces, and this study investigated the psychological effects of diverse orthoptera calls on Japanese university students. The results showed that an increased number of species led to higher sound preferences. Factors such as calmness, beauty, musicality, and depth were extracted, and the scores for beauty and musicality increased with an increased number of species. The combination of multiple species resulted in a favorable evaluation due to the harmonization of sounds and diversification of rhythms on the time axis.