Gravel et al., 2006 Rosen et al., 2012 Takesian et al., 2012 Liberman et al., 2015 Mowery et al., 2015). Nonetheless, there is evidence to suggest that even transient or mild levels of hearing loss during a critical period can lead to lasting effects in the central and peripheral auditory system (e.g. However, in contrast to the literature on deafness, much less is known about the effects of mild- (21–40 dB HL) to-moderate (41–70 dB HL British Society of Audiology, 2011) SNHL (MMHL) on the developing auditory pathway. Deafness-induced changes have also been identified in humans, namely, degeneration of spiral ganglion cells in the cochlea ( Nadol et al., 1989), a reduction of volume of neurons in the cochlear nucleus ( Seldon and Clark, 1991 Chao et al., 2002) and a functional reorganisation of cortical activity ( Neville et al., 1998) following congenital profound (>95 dB HL) sensorineural hearing loss (SNHL). Animal studies have shown marked differences in the anatomy, physiology, and functionality of the central auditory pathway following cochlear ablation, pharmacological neonatal deafening, and congenital deafness ( Shepherd and Hardie, 2001 Berger et al., 2017 see Butler and Lomber, 2013, for a review). The structure and function of the adult auditory system is dependent upon stimulation received during maturation ( Kral and Sharma, 2012). Our findings demonstrate that even a mild-to-moderate hearing loss during early-to-mid childhood can lead to changes in the neural processing of sounds in late childhood/adolescence. Children who had shown significant MMNs at Time 1 showed MMNs that were reduced and, for nonspeech, absent at Time 2. Six years later, we re-tested a subset of the younger (now older) children with MMHL (n = 13). At Time 1, younger children with MMHL (8–12 years n = 23) showed age-appropriate mismatch negativities (MMNs) to sounds, but older children (12–16 years n = 23) did not. ![]() Here, we used a longitudinal design to examine late auditory evoked responses and mismatch responses to nonspeech and speech sounds for children with MMHL. ![]() However, less is known about the effects of mild-to-moderate sensorineural hearing loss (MMHL) during development. Auditory deprivation in the form of deafness during development leads to lasting changes in central auditory system function.
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