Amount of Hearing Aid Use Impacts Neural Oscillatory Dynamics Underlying Verbal Working Memory Processing for Children With Hearing Loss

Abstract

Objectives: Children with hearing loss (CHL) may exhibit spoken language delays and may also experience deficits in other cognitive domains including working memory. Consistent hearing aid use (i.e., more than 10 hours per day) ameliorates these language delays; however, the impact of hearing aid intervention on the neural dynamics serving working memory remains unknown. The objective of this study was to examine the association between the amount of hearing aid use and neural oscillatory activity during verbal working memory processing in children with mild-to-severe hearing loss. Design: Twenty-three CHL between 8 and 15 years-old performed a letter-based Sternberg working memory task during magnetoencephalography (MEG). Guardians also completed a questionnaire describing the participants’ daily hearing aid use. Each participant’s MEG data was coregistered to their structural MRI, epoched, and transformed into the time–frequency domain using complex demodulation. Significant oscillatory responses corresponding to working memory encoding and maintenance were independently imaged using beamforming. Finally, these whole-brain source images were correlated with the total number of hours of weekly hearing aid use, controlling for degree of hearing loss. Results: During the encoding period, hearing aid use negatively correlated with alpha-beta oscillatory activity in the bilateral occipital cortices and right precentral gyrus. In the occipital cortices, this relationship suggested that with greater hearing aid use, there was a larger suppression of occipital activity (i.e., more negative relative to baseline). In the precentral gyrus, greater hearing aid use was related to less synchronous activity (i.e., less positive relative to baseline). During the maintenance period, hearing aid use significantly correlated with alpha activity in the right prefrontal cortex, such that with greater hearing aid use, there was less right prefrontal maintenance-related activity (i.e., less positive relative to baseline). Conclusions: This study is the first to investigate the impact of hearing aid use on the neural dynamics that underlie working memory function. These data show robust relationships between the amount of hearing aid use and phase-specific neural patterns during working memory encoding and maintenance after controlling for degree of hearing loss. Furthermore, our data demonstrate that wearing hearing aids for more than ~8.5 hours/day may serve to normalize these neural patterns. This study also demonstrates the potential for neuroimaging to help determine the locus of variability in outcomes in CHL.

Auditory experience modulates fronto-parietal theta activity serving fluid intelligence

“…Given the increasing evidence that consistent hearing aid use moderates language, executive function, and academic outcomes in CHH 12 , 18 , 26 and may have cascading effects on cognitive neurophysiology, 27 we next sought to determine whether the number of hours that CHH wore their hearing aids also modified their neural dynamics underlying abstract reasoning. To this end, the total number of hours of hearing aid use (Monday–Sunday, during the school year) were entered into a voxel-wise whole-brain correlation analysis with theta ERS and alpha ERD maps separately, with BEPTA acting as a covariate.…”

“…This sample size was selected based on our prior work showing differences in brain activity between CHH and CNH. 27 , 32 All data collection occurred at the University of Nebraska Medical Center. Exclusionary criteria included any medical illness affecting CNS function, current or previous major neurological or psychiatric disorder, history of head trauma, current substance abuse, and/or the presence of irremovable ferromagnetic material in or on the body (e.g.…”

“…imaging) in this study were derived through a two-stage statistical analysis of the sensor-level spectrograms across the entire array of gradiometers (magnetometer data was not analyzed) during the 4 s stimulus presentation window, in line with our previous studies. 27 , 31 , 32 , 39 Each data point in the spectrogram was initially evaluated using a mass univariate approach based on the general linear model. To reduce the risk of false-positive results while maintaining reasonable sensitivity, a two-stage procedure was followed to control for Type 1 error.…”

“… 12 , 18 , 26 Crucially, we recently reported that the amount of hearing aid use also significantly relates to neurophysiological markers of cognitive processing in CHH, such that greater hearing aid use (especially more than ∼8.5 h per day) served to significantly normalize patterns of neural activity during working memory processing in CHH. 27 Nonetheless, the effects of individual differences in auditory experience on non-verbal intelligence have rarely been described in previous studies, and to date, there has been no investigation of the underlying neurophysiology.…”

Gamma-Band Modulation in Parietal Area as the Electroencephalographic Signature for Performance in Auditory–Verbal Working Memory: An Exploratory Pilot Study in Hearing and Unilateral Cochlear Implant Children

“…Indeed, there has been considerable interest in determining the locus of outcome variability in children with CI in recent years. Researchers have identified that cognitive factors, such as WM, are critical in the healthy development of children with CI, and despite the effect of CI-treated profound hearing loss on auditory and visual–verbal WM performance, its neural correlates remain unclear [ 48 , 53 ]. In particular, to our knowledge, the EEG power spectrum related to the audio-visual WM task has not been explored in children CI users.…”