Hearing under stress: IV. a speech delivery communication system for utilization in high ambient noise environments

Many communication systems have been devised to improve the individual's ability to receive speech information in the presence of ambient noise. The purpose of this study was to determine the effectiveness of a speech delivery system which combined a high degree of ambient noise attenuation with the ear's own natural amplification phenomenon--the occlusion effect. It was demonstrated that occlusion of the auditory system at the level of the external auditory meatus, in conjuction with bone-conducted speech stimuli presented at the mastoid, was most effective in providing high speech discrimination ability with significant attenuation of ambient noise.