Objectives: The objectives of the present study were to investigate the effects of age-related changes in extended high-frequency (EHF) hearing, peripheral neural function, working memory, and executive function on speech perception deficits in middle-aged individuals with clinically normal hearing. Design: We administered a comprehensive assessment battery to 37 participants spanning the age range of 20 to 56 years. This battery encompassed various evaluations, including standard and EHF pure-tone audiometry, ranging from 0.25 to 16 kHz. In addition, we conducted auditory brainstem response assessments with varying stimulation rates and levels, a spatial release from masking (SRM) task, and cognitive evaluations that involved the Trail Making test (TMT) for assessing executive function and the Abbreviated Reading Span test (ARST) for measuring working memory. Results: The results indicated a decline in hearing sensitivities at EHFs and an increase in completion times for the TMT with age. In addition, as age increased, there was a corresponding decrease in the amount of SRM. The declines in SRM were associated with age-related declines in hearing sensitivity at EHFs and TMT performance. While we observed an age-related decline in wave I responses, this decline was primarily driven by age-related reductions in EHF thresholds. In addition, the results obtained using the ARST did not show an age-related decline. Neither the auditory brainstem response results nor ARST scores were correlated with the amount of SRM. Conclusions: These findings suggest that speech perception deficits in middle age are primarily linked to declines in EHF hearing and executive function, rather than cochlear synaptopathy or working memory.

In this study, the physiological and perceptual correlates of auditory function in student musicians and nonmusicians with normal hearing thresholds were investigated. The measures involved were auditory brainstem responses as a function of stimulation rate, spatial release from masking, and word intensity rollover functions. The results indicated that as the stimulation rate was increased, the wave I amplitude reductions were more abrupt in musicians than in nonmusicians. However, no significant group differences were observed for speech tasks. There were also no significant correlations between the results of speech perception and the measures of peripheral neural function.

Background: Spatial release from masking (SRM) is the improvement in speech intelligibility when the masking signals are spatially separated from the target signal. Young, normal- hearing listeners have a robust auditory sys-tem that is capable of using the binaural cues even with a very small spatial separation between the target and the maskers. Prior studies exploring SRM through simulated cochlear implant (CI) speech have been completed using substantial spatial separations, exceeding 45° between the target signal and masking signals. Nevertheless, in re-al-world conversational scenarios, the spatial separation between the target and the maskers may be considerably less than what has been previously investigated. This study presents SRM data utilizing simulated CI speech with young, normal-hearing listeners, focusing on smaller but realistic spatial separations between the target and the maskers. Methods: Twenty-five young, normal-hearing listeners participated in this study. Speech identification thresholds, the target-to-masker ratio required to accurately identify 50% of the target words, were measured for both natural speech and simulated CI speech. Results: The results revealed that young, normal-hearing listeners had significantly higher speech identification thresholds when presented with simulated CI speech in comparison to natural speech. Furthermore, the amount of SRM was found to be greater for natural speech than for the simulated CI speech. Conclusions: The data suggests that young normal-hearing individuals are capable of utilizing the interaural level difference cues in the simulated cochlear implant signal to achieve masking release at reduced spatial separations between the target and the maskers, highlighting the auditory system’s capability to extract these interaural cues even in the presence of degraded speech signals.

Misophonia is a condition characterized by intense, involuntary distress or anger in response to specific sounds, often leading to irritation or aggression. While the condition is recognized for its emotional and behavioral impacts, little is known about its physiological and perceptual effects. The current study aimed to explore the physiological correlates and perceptual consequences of misophonia through a combination of electrophysiological, perceptual, and cognitive assessments. Seventeen individuals with misophonia and sixteen control participants without the condition were compared. Participants completed a comprehensive battery of tests, including (a) cortical event-related potentials (ERPs) to assess neural responses to standard and deviant auditory stimuli, (b) the spatial release from the speech-on-speech masking (SRM) paradigm to evaluate speech segregation in background noise, and (c) the flanker task to measure selective attention and cognitive control. The results revealed that individuals with misophonia exhibited significantly smaller mean peak amplitudes of the N1 and N2 components in response to oddball tones compared to controls. This suggests a potential underlying neurobiological deficit in misophonia patients, as these components are associated with early auditory processing. However, no significant differences between each group were observed in the P1 and P2 components regarding oddball tones or in any ERP components in response to standard tones. Despite these altered neural responses, the misophonia group did not show differences in hearing thresholds, speech perception abilities, or cognitive function compared to the controls. These findings suggest that while misophonia may involve distinct neurophysiological changes, particularly in early auditory processing, it does not necessarily lead to perceptual deficits in speech perception or cognitive function.

Objectives: Musicians face an increased risk of hearing loss due to prolonged and repetitive exposure to high-noise levels. Detecting early signs of hearing loss, which are subtle and often elusive to traditional clinical tests like pure-tone audiometry, is essential. The objective of this study was to investigate the impact of noise exposure on the electrophysiological and perceptual aspects of subclinical hearing damage in young musicians with normal audiometric thresholds. Design: The study included 33 musicians and 33 nonmusicians, all aged between 21 and 35 years, with normal audiometric thresholds. Participants underwent a comprehensive test battery, which encompassed standard and extended high-frequency (EHF) pure-tone audiometry (0.25 to 16 kHz), a Noise Exposure Structured Interview, auditory brainstem responses (ABRs) to clicks at various presentation rates and levels, thresholds for detecting interaural envelope time difference, and a spatial release from masking (SRM) paradigm in which the target speech was presented in the presence of either colocated or spatially separated time-reversed two-talker babble. Results: The results indicated the musician group reported greater lifetime noise exposure than the nonmusician group, but the Noise Exposure Structured Interview scores were neither correlated with the ABR results nor with the speech perception outcomes. The ABR analyses indicated diminished level-dependent growth and increased rate-dependent decline in wave I amplitudes among musicians compared with nonmusicians. The student musicians exhibited better binaural envelope processing skills than nonmusicians, emphasizing their perceptual advantages in auditory processing associated with musicianship. Speech perception results indicated no significant differences in SRM between student musicians and nonmusicians. However, in both groups, individuals with poorer EHF hearing exhibited reduced SRM compared with those with normal EHF hearing, underscoring the importance of assessing and addressing EHF hearing. Conclusions: Student musicians exhibit peripheral neural deficits; however, no clear relation was found between these neural deficits and their perceptual skills. Notably, reduced EHF thresholds were clearly related to reduced SRM, which poses a challenge for speech perception in complex multi-talker environments, affecting both musicians and nonmusicians alike.

The use of remote testing to collect behavioral data has been on the rise, especially after the COVID-19 pandemic. Here we present psychometric functions for a commonly used speech corpus obtained in remote testing and laboratory testing conditions on young normal hearing listeners in the presence of different types of maskers. Headphone use for the remote testing group was checked by supplementing procedures from prior literature using a Huggins pitch task. Results revealed no significant differences in the measured thresholds using the remote testing and laboratory testing conditions for all the three masker types. Also, the thresholds measured obtained in these two conditions were strongly correlated for a different group of young normal hearing listeners. Based on the results, excellent outcomes on auditory threshold measurements where the stimuli are presented both at levels lower than and above an individual’s speech-recognition threshold can be obtained by remotely testing the listeners.