This research aims to explore the impact of variations in apparent sound source width and position on emotional and physiological responses among listeners, with a particular focus on the domain of virtual reality applications. While sound is recognized as a potent elicitor of strong emotions, the specific role of spatial characteristics, such as apparent sound source width, has not been systematically analyzed. The authors’ previous study has indicated that the spatial distribution of sound can alter perceptions of scariness. In contrast, the current study explores whether adjustments in apparent sound source width can significantly affect emotional valence and arousal, as well as human physiological metrics. The objective of this study was to investigate the impact of a single sound source width and its horizontal position on emotional engagement, thereby providing valuable insights for advancements in immersive audio experiences. Our experiments involved conducting listening tests in a spatial sound laboratory, utilizing a circular setup of sixteen loudspeakers to present a range of audio stimuli drawn from five selected recordings. The stimuli were manipulated based on two key parameters: the apparent sound source width and the spatial positioning of the sound source (front, back, left, or right). Participants assessed their emotional reactions using the Self-Assessment Manikin (SAM) pictogram method. Physiological data, including electroencephalogram, blood volume pressure, and electrodermal activity was collected in real-time via wearable sensors consisting of an EEG headset and a finger-attached device.
