The Occlusion Effect and Ampclusion Effect

ABSTRACT

When an individual speaks, laryngeal vocalizations are generated in the ear canal. Normally, these vibrations escape from the external auditory meatus. When the ear canal is blocked by an earmold or hearing aid shell, these vibrations translate into increased low frequency SPL reaching the tympanic membrane. This bone-conducted phenomenon is called the occlusion effect. Hearing aid users also may experience altered perception of their voices due to air conduction of the sound amplified by the hearing instrument. Because this second phenomenon is related to amplification it is termed ampclusion. The origin of the problems can be determined through a systematic approach. Once determined, the effects can be relieved via changes in otoplastics, electroacoustics, and/or counseling.

KEYWORDS

Occlusion - ampclusion - bone conduction - otoplastics - electroacoustics

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