Vent Configurations on Subjective and Objective Occlusion Effect

Abstract

The current study reexamined the effect of vent diameters on objective and subjective occlusion effect (OE) while minimizing two possible sources of variability. Nine hearing-impaired participants with primarily a high-frequency hearing loss were evaluated. Laser shell-making technology was used to make ear inserts of completely-in-the-canal (CIC) hearing aids for the study. This was to minimize any potential slit leakage from the inserts. The vent dimensions were systematically altered during the study. Participants sustained /i/ for 5 sec, and the real-ear occluded response was measured with a custommade program that performed frequency averaging to reduce response variability. Participants also repeated the phrase "Baby Jeannie is teeny tiny" and rated their own voice. The results showed a systematic change in the objective OE and subjective ratings of OE as the vent diameter was modified. Furthermore, a significant correlation was seen between subjective rating and objective occlusion effect.Key Words: Laser shell-making, occlusion effect, reverse horn vent, subjective occlusion ratings, vent Abbreviations: AE = ampclusion effect; CIC = completely in the canal; OE = occlusion effect; REOR voc = real-ear occluded response during vocalization; REUR voc = real-ear unoccluded response during vocalization; RMS = root mean square SumarioEl actual estudio re-examinó el efecto de los diferentes diámetros en el orificio de ventilación sobre el efecto de oclusión (OE), objetiva y subjetivamente, minimizando dos posibles fuentes de variabilidad. Se evaluó a nueve participantes hipoacúsicos con pérdidas auditivas primariamente en las altas frecuencias. Se utilizó una tecnología laser de fabricación de conchas para producir, para el estudio, dispositivos de inserción de auxiliares auditivos completamente en el canal (CIC). Esto se hizo para minimizar cualquier fuga de hendidura de los insertos. Las dimensiones de orificio de ventilación fueron sistemáticamente alteradas durante el estudio. Los participantes produjeron una /i/ sostenida por 5 segundos, y se midieron las respuestas ocluidas de oído real con un programa hecho a la medida que realizaba promediaciones de la frecuencia para reducir la variabilidad en la respuesta. Los participantes también repitieron la frase "Baby Jeannie is teeny tiny" y calificaron su propia voz. Los resultados mostraron un cambio sistemático en las apreciaciones objetivas y subjetivas del OE conforme se modificó el tamaño del orificio de ventilación. Más aún, se vio una correlación significativa entre la apreciación subjetiva y el efecto objetivo de oclusión.

An active hearing protection device for musicians

“…2 that the SPL increase caused by occlusion effect occurs in the lower frequencies of the speech bandwidth. This transfer function is only an approximation of the SPL increase caused by occlusion effect, but it is generally consistent with other similar measurements made by [2] or [3].…”

Comparison of Vent Effects between a Solid Earmold and a Hollow Earmold

“…Furthermore, while it is gratifying to know that a hollow earmold could reduce the OE, it is unclear if this OE reduction comes at a ''cost'' to the wearers. At least in a solid earmold, Kuk et al (2005) showed that while an increase in vent diameter led to a decrease in OE, it also decreased the amount of maximum available gain and increased the contribution of direct sounds at the eardrum. These changes could affect the performance of the hearing aids.…”

“…Another solution is the use of vents. For example, Kuk et al (2005) showed a systematic decrease in the OE as the vent diameter of an earmold was increased. The amount of reduction was best characterized by a decaying function with the most OE reduction when the vent was first introduced (from 0-1 mm).…”

Perceived Occlusion and Comfort in Receiver-in-the-Ear Hearing Aids

“…Participants made a judgment on sound quality, not specifically occlusion, after repeating only one sentence. Therefore, the study is not a perfect example of self-perceived occlusion for those wearing hearing aids (Kuk, Keenan, & Lau, 2005). Kiessling, Brenner, Jespersen, Groth, and Jensen (2005) quantified the occlusion effect with conventional ear molds, shell type ear molds with a novel vent design with equivalent cross-sectional vent areas, and non-occluding soft silicone ear tips.…”