Relating Suprathreshold Auditory Processing Abilities to Speech Understanding in Competition

Abstract

(1) Background: Difficulty hearing in noise is exacerbated in older adults. Older adults are more likely to have audiometric hearing loss, although some individuals with normal pure-tone audiograms also have difficulty perceiving speech in noise. Additional variables also likely account for speech understanding in noise. It has been suggested that one important class of variables is the ability to process auditory information once it has been detected. Here, we tested a set of these “suprathreshold” auditory processing abilities and related them to performance on a two-part test of speech understanding in competition with and without spatial separation of the target and masking speech. Testing was administered in the Portable Automated Rapid Testing (PART) application developed by our team; PART facilitates psychoacoustic assessments of auditory processing. (2) Methods: Forty-one individuals (average age 51 years), completed assessments of sensitivity to temporal fine structure (TFS) and spectrotemporal modulation (STM) detection via an iPad running the PART application. Statistical models were used to evaluate the strength of associations between performance on the auditory processing tasks and speech understanding in competition. Age and pure-tone-average (PTA) were also included as potential predictors. (3) Results: The model providing the best fit also included age and a measure of diotic frequency modulation (FM) detection but none of the other potential predictors. However, even the best fitting models accounted for 31% or less of the variance, supporting work suggesting that other variables (e.g., cognitive processing abilities) also contribute significantly to speech understanding in noise. (4) Conclusions: The results of the current study do not provide strong support for previous suggestions that suprathreshold processing abilities alone can be used to explain difficulties in speech understanding in competition among older adults. This discrepancy could be due to the speech tests used, the listeners tested, or the suprathreshold tests chosen. Future work with larger numbers of participants is warranted, including a range of cognitive tests and additional assessments of suprathreshold auditory processing abilities.

Individual Differences Elucidate the Perceptual Benefits Associated with Robust Temporal Fine-Structure Processing

“…Our results, therefore, affirm the contribution of TFS coding for enabling robust central auditory processing, possibly with lower listening effort. The fact that the group difference in reaction times did not translate into the masking-release metrics underscores the need to investigate cognitive factors beyond performance/score metrics to fully characterize the importance of different peripheral cues (Loughrey et al, 2018; Nuesse et al, 2018; Humes, 2021; Gallun et al, 2022).…”

Validation of the adaptive scan method in the quest for time-efficient methods of testing auditory processes

“…These parameters were chosen so that the number of trials and time in task were roughly equivalent across methods. These parameters are the same ones used in previous publications of our group using the T&W method (Diedesch et al, 2021 ; Gallun et al, 2022 ; Lelo de Larrea-Mancera et al, 2020 , 2022 ; Srinivasan, 2020 ). In the case of the CS method, a pre-defined number of trials (16) per stimulus level (nine) that should be sufficient to calculate a psychometric function was chosen.…”

Effects of Temporal Processing on Speech-in-Noise Perception in Middle-Aged Adults

“…Information from TFS plays a role in the perception of pitch, sound localization, and the ability to detect a signal against a fluctuating masker [ 7 , 37 ]—all attributes critical to sound source segregation, such as discerning speech-in-noise. Indeed, perceptual measures of TFS sensitivity have repeatedly helped reveal an association between poor TFS sensitivity and deficits in speech-in-noise perception across various clinical populations (e.g., hearing loss and traumatic brain injury) [ 7 , 38 , 39 ], including aging adults with normal audiometric thresholds [ 10 , 40 , 41 ]. For this reason, we included a measure of binaural TFS sensitivity using a classic psychoacoustic task: frequency modulation (FM) detection [ 41 , 42 ].…”