Mismatched response predicts behavioral speech discrimination outcomes in infants with hearing loss and normal hearing

Abstract

Children with hearing loss (HL) remain at risk for poorer language abilities than normal hearing (NH) children despite targeted interventions; reasons for these differences remain unclear. In NH children, research suggests speech discrimination is related to language outcomes, yet we know little about it in children with HL under the age of 2 years. We utilized a vowel contrast, /a‐i/, and a consonant‐vowel contrast, /ba‐da/, to examine speech discrimination in 47 NH infants and 40 infants with HL. At Mean age =3 months, EEG recorded from 11 scalp electrodes was used to compute the time‐frequency mismatched response (TF‐MMRSE) to the contrasts; at Mean age =9 months, behavioral discrimination was assessed using a head turn task. A machine learning (ML) classifier was used to predict behavioral discrimination when given an arbitrary TF‐MMRSE as input, achieving accuracies of 73% for exact classification and 92% for classification within a distance of one class. Linear fits revealed a robust relationship regardless of hearing status or speech contrast. TF‐MMRSE responses in the delta (1–3.5 Hz), theta (3.5–8 Hz), and alpha (8–12 Hz) bands explained the most variance in behavioral task performance. Our findings demonstrate the feasibility of using TF‐MMRSE to predict later behavioral speech discrimination.

Relationship between Behavioral Infant Speech Perception and Hearing Age for Children with Hearing Loss

“…The reasons for data loss were as follows: failure to condition to the task for the second contrast (three CNH, three CHH), loss to follow-up after completing one contrast (one CNH, one CHH), and modification in the presentation of the stimuli level for /ba-da/ 50 versus 65 dBA SPL for the first level assessed (eight CNH, one CHH). The data for 43 children with CNH [ 16 ] and 11 children with CHH [ 16 ] have also been reported in previous studies. Amplification and speech perception data were obtained from 57 infants (28 males and 29 females) with bilateral sensorineural hearing losses ranging from mild to severe.…”

“…Future work should include some measure of test-retest reliability across multiple visits. Of note, a subset of our CNH was previously reported in Uhler et al [ 16 ], for which they completed cortical evoked potential testing and exhibited passive discrimination of our consonant and vowel contrasts. The group tested in this study also lacks generalizability to CHH who did not meet the JCIH guidelines.…”

“…Despite these improvements, there continues to be wide variability in spoken language outcomes (i.e., mean vocabulary quotient = 77.6, SD = 19.7; [ 11 ]), word learning abilities [ 12 ], and academic achievement [ 13 , 14 , 15 ] for CHH. Based on results from our previous research, we suggest that such variability in outcomes may be due to differences in speech perception abilities during infancy, which are poorer for infants with hearing loss [ 16 ], and may partially be explained by reduced auditory access to the full speech spectrum even after being fitted with hearing aids.…”

EEG Alpha Band Responses Reveal Amplification Benefits in Infants with Hearing Loss

“…Our recent work [ 28 , 29 , 30 ] has focused on developing and refining an objective, MMR measure to assess speech perception of the neural correlates in response to changes in speech sounds in young infants with bilateral mild-to-severe permanent hearing losses recently fit with hearing aids. Using a time-frequency analysis of MMR responses in IHH (tested while wearing their hearing aids) and INH, we demonstrated a relationship between MMR in early infancy (1–6 months of age) and later behavioral measures of speech perception at 9–11 months of age [ 28 ]. We found that early brain responses (~100–300 ms after stimulation) in the 6–12 Hz frequency range, the alpha band, were positively correlated with later speech discrimination scores, assessed behaviorally.…”

Pre-attentive fundamental frequency processing in Mandarin-speaking children with cochlear implants as revealed by the peak latency of positive mismatch response

“…In recent decades, the event-related potential (ERP) technique has been applied to auditory research in pediatric CI users, including music and lexical tone perception ( Kileny et al, 1997 ; Singh et al, 2004 ; Henkin et al, 2008 ; Torppa et al, 2012 ; Liang et al, 2014 ; Sharma et al, 2015 ; Fu et al, 2016 ). Numerous studies have demonstrated that MMRs, which reflect automatic stimuli discrimination at the pre-attentive stage (i.e., no attention or behavioral responses are required for completing tasks) ( Segalowitz and Barnes, 1993 ; Luck, 2014 ) are reliable biomarkers predicting behavioral performance ( Tiitinen et al, 1994 ; Benasich et al, 2006 ; Perez et al, 2017 ; Uhler et al, 2021 ). Accordingly, in this study, MMRs are employed as the electrophysiological indicators of F0 processing in Mandarin-speaking children with CIs at the pre-attentive stage.…”