Electronic Thesis and Dissertation Repository


Master of Science


Health and Rehabilitation Sciences


Ewan Macpherson


Head movements are known to be beneficial during sound localization because the auditory system can integrate the dynamic cues generated by head movement while maintaining a spatial representation of the position and orientation of the head-in-space. To measure the extent to which vestibular and proprioceptive cues influence processing of dynamic sound localization cues resulting from head rotation, we measured the ability of normally hearing listeners to localize front/back sources of low-frequency sounds while the two modalities were individually or congruently stimulated. Targets were presented over headphones during head rotations using virtual auditory space methods. Dynamic localization cues corresponded to head-in-space and/or head-on-body angle. Discrimination was accurate in passive and active head rotation conditions, but near chance in conditions lacking head-in-space motion, suggesting that among the two sensorimotor cues, vestibular inputs are necessary and sufficient to inform the auditory system about head movement, whereas proprioceptive cues are neither necessary nor sufficient.