Modification of Speech Discrimination in Patients with Binaural Asymmetrical Hearing Loss

Abstract

Ten patients with bilateral asymmetrical hearing losses were tested for differences in speech discrimination scores under the following listening conditions: poorer ear under earphone; better ear under earphone; sound field, ears unoccluded; and sound field, poorer ear occluded. A patient manifesting a bilateral asymmetrical hearing loss may not be able to either separate or integrate two speech signals; however, occlusion of the poorer ear may be an advantageous means of obtaining maximum speech discrimination. Examination of the speech discrimination scores indicates the existence of detrimental interaction between ears exhibiting bilateral asymmetrical hearing loss. These findings also indicate that when the difference between ears is greater, speech discrimination is better than when asymmetry approximates symmetry. Apparently, the greater the impairment in the better ear, the greater the results to be gained by occluding the poorer ear. These findings were interpreted as being relevant in determining candidacy for binaural amplification. Such candidacy should be determined on the basis of speech discrimination scores obtained from each ear independently, and the combined effect of both aids.

Unilateral Hearing Loss Is Associated With Worse Speech-Language Scores in Children

“…However, studies in children and adults with asymmetric BHL show that sound localization and speech discrimination are more difficult and outcomes are poorer than with symmetric BHL. 36-39 We speculate that when the difference in hearing between ears exceeds a threshold level, a person with UHL may experience difficulty with sound localization or speech discrimination in noise similar that experienced by those with asymmetric BHL. However, further research is necessary to determine whether a threshold effect might exist.…”

Binaural-Bimodal Fitting or Bilateral Implantation for Managing Severe to Profound Deafness: A Review

“…Notwithstanding the accumulating research studies in support of the provision of binaural hearing devices, there may be some people who have deficits in binaural processing such that better performance is obtained with a unilateral device than with bilateral devices (this phenomenon has been observed for bilateral hearing aid wearers; see for example, Arkebauer et al 122 and Jerger et al 123 ). Potential causes hypothesized include asymmetrical distortion in the two cochleae and distorted or delayed interhemispheric transmission via the corpus callosum.…”

Are Two Ears Not Better Than One?

“…One possible reason for the better performance Walden and Walden (2005) found with monaural amplification relates to the phenomenon known as binaural interference. Binaural interference is believed to be the result of the inappropriate fusion of the signals presented to the two ears (Arkebauer et al, 1971;Jerger et al, 1993;Chmiel et al, 1997). Indeed, there are data from case studies demonstrating that some older individuals perform more poorly on speech-in-noise tasks when wearing two hearing aids as compared to one (Hurley, 1993;Jerger et al, 1993;Chmiel et al, 1997;Carter et al, 2001;Holmes, 2003).…”

“…Indeed, there are data from case studies demonstrating that some older individuals perform more poorly on speech-in-noise tasks when wearing two hearing aids as compared to one (Hurley, 1993;Jerger et al, 1993;Chmiel et al, 1997;Carter et al, 2001;Holmes, 2003). Although Chmiel et al (1997) implied that binaural interference is a problem seen particularly with older adults, other investigators have reported binaural interference in younger patients (i.e., Arkebauer et al, 1971).…”