Date of Degree


Document Type

Capstone Project

Degree Name





Adrienne Rubinstein

Subject Categories

Speech Pathology and Audiology


occlusion effect, bone conduction, insert earphones


The occlusion effect is a well-known phenomenon that can affect audiological testing. Sound energy that would typically escape is trapped when covering the ear(s) and reflected back toward the inner ear. This increases the intensity of the sound, resulting in the “appearance” of a more sensitive threshold. Many aspects of the occlusion effect have been well researched and understood, however there are still aspects that warrant further investigation, such as the degree of occlusion with insert earphones when using partial versus full insertion and whether one or both of the ears are occluded. A within-subject design (n=5) was utilized to measure the occlusion effect at 250-1000 Hz in a variety of different occlusion conditions of clinical relevance. Results revealed occlusion effects in all conditions for at least some participants , although they were greater with partial as compared to full insertion. Thus, results of the present study support the need to account for the occlusion effect prior to masking frequencies 250-1000 Hz in order to ensure sufficient noise in the non-test ear. There were no clinically significant differences in degree of occlusion when comparing one versus both ears This finding allows for a potentially time saving procedure of inserting both inserts into the ears after obtaining initial bone conduction thresholds, which would be more expedient in situations where masking for both ears is required.