This study investigates the relationship between auditory localization accuracy in the horizontal plane and the spontaneous translation and rotation of the head in response to an acoustic stimulus from an invisible sound source. Although a number of studies have suggested that localization ability improves with head movements, most of them measured the perceived source elevation and front-back disambiguation. We investigated the contribution of head movements to auditory localization in the anterior horizontal field in normal hearing subjects. A virtual reality scenario was used to conceal visual cues during the test through a head mounted display. In this condition, we found that an active search of the sound origin using head movements is not strictly necessary, yet sufficient for achieving greater sound source localization accuracy. This result may have important implications in the clinical assessment and training of adults and children affected by hearing and motor impairments.

This study investigates auditory localization in children with no motor deficits and a diagnosis of hearing impairment rehabilitated with bilateral cochlear implants or hearing aids. The contribution of head movement to sound source localization in the anterior horizontal field has been analyzed. A localization task took place in a virtual environment, where participants who could move their heads freely were asked to point to an invisible sound source. The source was rendered using a loudspeaker set arranged in a semi-circular array in the horizontal plane, while participants observed a neutral visual scene through a head-mounted display. This device also allowed for tracking the participants’ head and hand positions while they pointed to the auditory target. Investigating conditions in which no, one, or both ear devices were turned off, we found that asymmetrical hearing caused the largest head movements. The correlation between localization accuracy and pure tone audiometric thresholds measured when the ear devices were turned off as well as the correlation between such thresholds and the amount of head movement support the hypothesis that horizontal auditory localization is an ability that develops in synergy with active listening skills. This finding may have important implications for the clinical assessment and rehabilitation of adults and children affected by hearing impairment.