Background: Speech-in-noise (SIN) perception is known to be affected by sensorineural hearing loss (SNHL). This is not only related to reduced audibility but also to impaired basic auditory mechanisms essential for speech processing that are affected by cochlear damage. The goal of the present study was to investigate the impact of SNHL in childhood on temporal and spectral processing, as well as SIN perception.

Methods: Preliminary results are presented with data collected among 12 children with mild-to-moderate SNHL and aged between 5 and 10 years. They were presented with four SIN conditions: consonant versus word identification in speech-shaped noise (SSN) versus 2-talker babble noise. In parallel, auditory temporal (amplitude and frequency modulations- AM/FM- fluctuating at 4 or 20 Hz) and spectral ripple density (tested at 0.5 or 2 ripple-per-octave) detection thresholds were measured, along with receptive vocabulary (using the Peabody Picture Vocabulary test) and nonverbal working memory measures (using the forward and backward versions of the Corsi test). Thresholds of children with SNHL were compared to those of children with normal hearing (NH) of the same age range.

Results: As expected, children with SNHL performed more poorly than NH peers in all SIN tasks. They also showed worse FM and spectral detection thresholds but preserved or even improved AM detection. Preliminary analyses showed that SIN thresholds did not correlate with temporal or spectral cue detection, neither nonverbal working memory. Only a weak relationship between consonant identification and receptive vocabulary was found.

Conclusions: As observed in previous adult studies testing the effects of acquired SNHL, our results in children with congenital SNHL showed that this condition affects FM and spectral processing, but that AM processing is relatively preserved. Children with SNHL displayed elevated thresholds in all SIN tasks used and a strong inter-individual variability. However, the analyses so far have not revealed any auditory or cognitive factor that emerge as dominant predictors of SIN in children with SNHL. To better capture inter-individual variability and fully assess the effects of age and development, data collection must continue.