Link to the University of Pittsburgh Homepage
Link to the University Library System Homepage Link to the Contact Us Form

Influence of ear canal occlusion and air-conduction feedback on speech production in noise

Byrne, David (2014) Influence of ear canal occlusion and air-conduction feedback on speech production in noise. Doctoral Dissertation, University of Pittsburgh. (Unpublished)

Primary Text

Download (5MB) | Preview


Millions of workers are exposed to high noise levels on a daily basis. The primary concern for these individuals is the prevention of noise-induced hearing loss, which is typically accomplished by wearing of some type of personal hearing protector. However, many workers complain they cannot adequately hear their co-workers when hearing protectors are worn. There are many aspects related to fully understanding verbal communication between noise-exposed workers that are wearing hearing protection. One topic that has received limited attention is the overall voice level a person uses to communicate in a noisy environment. Quantifying this component provides a starting point for understanding how communication may be improved in such situations.
While blocking out external sounds, hearing protectors also induce changes in the wearer’s self-perception of his/her own voice, which is known as the occlusion effect. The occlusion effect and attenuation provided by hearing protectors generally produce opposite effects on that individual’s vocal output. A controlled laboratory study was devised to systematically examine the effect on a talker’s voice level caused by wearing a hearing protector and while being subjected to high noise levels. To test whether differences between occluded and unoccluded vocal characteristics are due solely to the occlusion effect, speech produced while subjects’ ear canals were occluded was measured without the subject effectively receiving any attenuation from the hearing protectors. To test whether vocal output differences are due to the reduction in the talker’s self-perceived voice level, the amount of occlusion was held constant while varying the effective hearing protector attenuation.
Results show the occlusion effect, hearing protector attenuation, and ambient noise level all to have an effect on the talker’s voice output level, and all three must be known to fully understand and/or predict the effect in a particular situation. The results of this study may be used to begin an effort to quantify metrics in addition to the basic noise reduction rating that may be used to evaluate a hearing protector’s practical usability/wearability. By developing such performance metrics, workers will have information to make informed decisions about which hearing protector they should use for their particular work environment.


Social Networking:
Share |


Item Type: University of Pittsburgh ETD
Status: Unpublished
CreatorsEmailPitt UsernameORCID
ETD Committee:
TitleMemberEmail AddressPitt UsernameORCID
Committee ChairPalmer, Catherinepalmercv@upmc.eduCVP
Committee MemberDurrant, Johndurrant@pitt.eduDURRANT
Committee MemberShaiman, Susanshaiman@pitt.eduSHAIMAN
Committee MemberVipperman, Jeffreyjsv@pitt.eduJSV
Committee MemberMurphy,
Date: 13 January 2014
Date Type: Publication
Defense Date: 25 September 2013
Approval Date: 13 January 2014
Submission Date: 21 November 2013
Access Restriction: No restriction; Release the ETD for access worldwide immediately.
Number of Pages: 160
Institution: University of Pittsburgh
Schools and Programs: School of Health and Rehabilitation Sciences > Communication Science and Disorders
Degree: PhD - Doctor of Philosophy
Thesis Type: Doctoral Dissertation
Refereed: Yes
Uncontrolled Keywords: Occlusion effect, Lombard effect, hearing protection
Date Deposited: 13 Jan 2014 19:14
Last Modified: 19 Dec 2016 14:41


Monthly Views for the past 3 years

Plum Analytics

Actions (login required)

View Item View Item