Investigating contextual effects in sound externalization

This study examines whether the perceived level of externalization of a virtual sound source (internalized versus externalized) can be influenced by the context, and in particular by the perceived level of externalization of a preceding source. Participants listened to pairs of sounds and had to judge whether the virtual source of the second sound (the target) was internalized or externalized. The first sound was either fully externalized (produced by a loudspeaker on the left of the participant) or internalized (reproduced diotically through headphones), while the target was reproduced through headphones as if coming from one of four loudspeakers in the room, at two distances (80 cm or 3 m) on the left or in front of the participant. Perceived externalization was, as expected, stronger for sounds originating from the side compared to those in front, and for distant sources compared to nearby ones, yet no significant influence of the preceding sound’s externalization level was found. Further Bayesian analyses are planned to confirm whether an absence of effect can be concluded.