Bone conduction reception: head sensitivity mapping.

This study sought to identify skull locations that are highly sensitive to bone conduction (BC) auditory signal reception and could be used in the design of military radio communication headsets. In Experiment 1, pure tone signals were transmitted via BC to 11 skull locations of 14 volunteers seated in a quiet environment. In Experiment 2, the same signals were transmitted via BC to nine skull locations of 12 volunteers seated in an environment with 60 decibels of white background noise. Hearing threshold levels for each signal per location were measured. In the quiet condition, the condyle had the lowest mean threshold for all signals followed by the jaw angle, mastoid and vertex. In the white noise condition, the condyle also had the lowest mean threshold followed by the mastoid, vertex and temple. Overall results of both experiments were very similar and implicated the condyle as the most effective location.