The impact of hearing aids and age-related hearing loss on auditory plasticity across three months – An electrical neuroimaging study

Abstract

The present study investigates behavioral and electrophysiological auditory and cognitive-related plasticity in three groups of healthy older adults (60-77 years). Group 1 was moderately hearing-impaired, experienced hearing aid users, and fitted with new hearing aids using non-linear frequency compression (NLFC on); Group 2, also moderately hearing-impaired, used the same type of hearing aids but NLFC was switched off during the entire period of study duration (NLFC off); Group 3 represented individuals with age-appropriate hearing (NHO) as controls, who were not different in IQ, gender, or age from Group 1 and 2. At five measurement time points (M1-M5) across three months, a series of active oddball tasks were administered while EEG was recorded. The stimuli comprised syllables consisting of naturally high-pitched fricatives (/sh/, /s/, and /f/), which are hard to distinguish for individuals with presbycusis. By applying a data-driven microstate approach to obtain global field power (GFP) as a measure of processing effort, the modulations of perceptual (P50, N1, P2) and cognitive-related (N2b, P3b) auditory evoked potentials were calculated and subsequently related to behavioral changes (accuracy and reaction time) across time. All groups improved their performance across time, but NHO showed consistently higher accuracy and faster reaction times than the hearing-impaired groups, especially under difficult conditions. Electrophysiological results complemented this finding by demonstrating longer latencies in the P50 and the N1 peak in hearing aid users. Furthermore, the GFP of cognitive-related evoked potentials decreased from M1 to M2 in the NHO group, while a comparable decrease in the hearing-impaired group was only evident at M5. After twelve weeks of hearing aid use of eight hours each day, we found a significantly lower GFP in the P3b of the group with NLFC on as compared to the group with NLFC off. These findings suggest higher processing effort, as evidenced by higher GFP, in hearing-impaired individuals when compared to those with normal hearing, although the hearing-impaired show a decrease of processing effort after repeated stimulus exposure. In addition, our findings indicate that the acclimatization to a new hearing aid algorithm may take several weeks.

Neurophysiological Measures of the Perception of Antismoking Public Service Announcements Among Young Population

“…The underlying idea of this procedure is that potential fields with few field lines presumably contain little information while scalp fields displaying much activity reflect the synchronous activation of a large number of intracranial neuronal elements. The GFP has been used in studies of perceptual, attentional, cognitive processing (e.g., Dierks and Maurer, 1989; Skrandies, 1991; Rodin, 1991; Michel et al, 1993; Rau et al, 2002; Boonstra et al, 2013; Ahonen et al, 2016) as well as in clinical studies (e.g., Rodin, 1990; Maurer et al, 1990; Strik et al, 1994; Favrod et al, 2017; Giroud et al, 2017; Iannilli et al, 2017). The GFP constitutes a good index for the temporal determination of information from cognitive studies, furthermore it has become a commonly used parameter for the time-domain analysis of EEG (as in the present study), since it allows to identify the maps of maximal electric field strength (hilliness).…”

Are you surprised to hear this? Longitudinal spectral speech exposure in older compared to middle‐aged normal hearing adults

“…The nonsense syllables (logatomes) asa (/′a:sa/), ascha (/′a:ʃa/), and afa (/’a:fa/) from the phoneme perception test (Boretzki et al ., ; Schmitt et al ., ) were used in our study. This stimulus material had been established previously in other studies using EEG (Giroud et al ., ,b). The logatomes /′a:ʃa/ and /′a:sa/, /’a:fa/ and /′a:sa/, and /′a:ʃa/ and /’a:fa/, respectively, were morphed together to create two equidistant intermediate stimuli (Zorn, ).…”

“…We used microstate analysis to investigate ERPs in a data‐driven and topographical manner (Giroud et al ., ,b). This method can be used for evaluating temporally stable topographical configurations, the so‐called microstates, measured with high‐density EEG (Pascual‐Marqui et al ., ), which can then be compared between groups and conditions.…”

“…Some studies have already shown that treatments such as hearing aids can facilitate cognitive‐related speech processing in the hearing impaired (Giroud et al ., ); for example, by showing that performance in working memory (Doherty & Desjardins, ) or performance in dichotic listening tasks (Lavie et al ., ) was higher in aided compared to unaided listening situations. It is likely that these benefits in cognitive‐related auditory tasks result from a facilitation of perceptual auditory processes during the use of hearing aids.…”

“…We expected to find better behavioral performance (higher ACC and lower RT) for deviants with stronger acoustic deviation to the standard stimulus than lower acoustic deviation (Johnson, ; Kok, ; Katayama & Polich, ; Gaál et al ., ; Giroud et al ., ,b). Furthermore, we expected the better behavioral detection of the deviant with strong acoustic deviation to be reflected in higher mean GFP and shorter onsets of the N2b and P3b components (Johnson, ; Kok, ; Katayama & Polich, ; Gaál et al ., ; Giroud et al ., ,b). We also hypothesized that older adults would evoke lower N2b and P3b mean GFPs and shorter onsets, as has been found in previous studies which compared older and younger adults (Schiff et al ., ; Juckel et al ., ).…”