Effect of Audibility and Suprathreshold Deficits on Speech Recognition for Listeners With Unilateral Hearing Loss

Assistive Technology for Adults with Hearing Aids

Although there is a strong trend of satisfaction with hearing aids, recent consumer surveys indicate that there are still challenges with understanding speech in background noise and low penetration of wireless technologies using many modern-day communication and audio devices, such as smartphones, tablets, and computers. For some listening and communication settings, many patients could benefit from assistive technology that exceeds the capabilities of their hearing aids. When patients are not wearing their hearing aids, such as during sleep, concerns about environmental awareness and safety begin to arise. This article describes some current assistive technologies and accessories that facilitate accessibility to other devices and to satisfy the patient's listening and communication needs.

Psychometric function for speech-in-noise tests accounts for word-recognition deficits in older listeners

Speech-in-noise (SIN) understanding in older age is affected by hearing loss, impaired central auditory processing, and cognitive deficits. SIN-tests measure these factors' compound effects by a speech reception threshold, defined as the signal-to-noise ratio required for 50% word understanding (SNR50). This study compared two standard SIN tests, QuickSIN (n = 354) in young and older adults and BKB-SIN (n = 139) in older adults (>60 years). The effects of hearing loss and age on SIN understanding were analyzed to identify auditory and nonauditory contributions to SIN loss. Word recognition in noise was modelled with individual psychometric functions using a logistic fit with three parameters: the midpoint (SNRα), slope (β), and asymptotic word-recognition deficit at high SNR (λ). The parameters SNRα and λ formally separate SIN loss into two components. SNRα characterizes the steep slope of the psychometric function at which a slight SNR increase provides a considerable improvement in SIN understanding. SNRα was discussed as being predominantly affected by audibility and low-level central auditory processing. The parameter λ describes a shallow segment of the psychometric function at which a further increase in the SNR provides modest improvement in SIN understanding. Cognitive factors in aging may contribute to the SIN loss indicated by λ.

Reorganization of auditory-visual network interactions in long-term unilateral postlingual hearing loss

Long-term unilateral hearing loss could reorganize the functional network association between the bilateral auditory cortices, while alterations of other functional networks need to be further explored. We attempted to investigate the pattern of the reorganization of functional network associations between the auditory and visual cortex caused by long-term postlingual unilateral hearing loss (UHI) and its relationship with clinical characteristics. Therefore, 48 patients with hearing loss caused by unilateral acoustic tumors and 52 matched healthy controls were enrolled, and their high-resolution structural MRI and resting-state functional MRI data were also collected to depict the brain network. Degree centrality (DC) was employed to evaluate the functional network association of the auditory-visual network interaction. Group comparisons were performed to investigate the network reorganization, and its correlations with clinical data were calculated. Compared with the healthy control group, patients with UHI showed significantly increased DC between the auditory network (superior temporal gyrus and the medial geniculate body) and the visual network. Meanwhile, this difference was positively correlated with the extent of hearing impairment, and the correlation was more significant with the ipsilateral superior temporal gyrus in cases of acoustic neuroma. These results suggest that long-term unilateral hearing impairment may lead to enhancement of the visual-auditory network interactions and that the degree of reorganization is positively correlated with the pure tone average (PTA) and is more significant for the ipsilateral superior temporal gyrus, which provides clinical evidence regarding cross-modal plasticity in the UHI and its lateralization.

Speech discrimination impairment of the worse-hearing ear in asymmetric hearing loss

OBJECTIVE

This study aimed to compare the difference in maximum speech discrimination score (SDSmax) of the worse-hearing ear in asymmetric hearing loss (ASHL) patients with that in symmetric hearing loss (SHL) patients.

DESIGN

We retrospectively reviewed medical records of patients with suspected hearing loss (HL) who underwent audiometric examinations. Patients were divided into two groups according to the difference in air conduction (AC) threshold between the right and left ears: the SHL group and the ASHL group.

STUDY SAMPLE

Of the 102 patients (204 ears), 74 (148 ears) had SHL, and 28 had ASHL.

RESULTS

The worse-hearing ear of ASHL patients exhibited a statistically significantly higher AC threshold and lower SDSmax, compared with ears of SHL patients and better-hearing ears of ASHL patients, and SDSmax exhibited a statistically significant negative correlation with AC threshold. The SDSmax was statistically significantly lower in the worse-hearing ear of the ASHL group than in moderate to severe HL ears of the SHL group, even though these groups had comparable AC thresholds.

CONCLUSIONS

ASHL patients' worse-hearing ear exhibited a lower SDSmax than SHL patients' ears, despite a comparable AC threshold. Management of hearing impairment in ASHL patients should receive more attention.