Deficits in auditory temporal and spectral resolution in language-impaired children

Abstract

Between 3 and 6 per cent of children who are otherwise unimpaired have extreme difficulties producing and understanding spoken language. This disorder is typically labelled specific language impairment. Children diagnosed with specific language impairment often have accompanying reading difficulties (dyslexia), but not all children with reading difficulties have specific language impairment. Some researchers claim that language impairment arises from failures specific to language or cognitive processing. Others hold that language impairment results from a more elemental problem that makes affected children unable to hear the acoustic distinctions among successive brief sounds in speech. Here we report the results of psychophysical tests employing simple tones and noises showing that children with specific language impairment have severe auditory perceptual deficits for brief but not long tones in particular sound contexts. Our data support the view that language difficulties result from problems in auditory perception, and provide further information about the nature of these perceptual problems that should contribute to improving the diagnosis and treatment of language impairment and related disorders.

Learning problems, delayed development, and puberty

“…In that experiment, we measured tone-detection thresholds in five conditions: a long tone presented during a noise and a brief tone presented before, at the beginning of, toward the middle of, or after that noise. Compared with age-matched controls, the mean detection thresholds for the affected children ranged from completely normal (for the long tone presented during the noise) to severely impaired (for the brief tone presented before the noise), seeming to indicate that the perceptual deficits of children with specific language impairment only occurred in particular sound contexts (10). The evidence for a developmental delay emerged from analyses of data on these same conditions obtained from individuals with different LPs.…”

“…The remaining 54 listeners (26 males and 28 females) had clinical diagnoses of specific language impairment (n ϭ 12), dyslexia (n ϭ 27), or central auditory processing disorder (n ϭ 15) and formed the sample with LPs. We previously reported the data of 54 of the 61 controls (10,20) and 8 of the 54 LP listeners (10).…”

“…The stimuli and procedure have been described (10,20). Briefly, the tone to be detected had a frequency of 1,000 Hz and a total duration of 20 or 200 ms.…”

“…We previously observed deficiencies in this ability in a group of 8-year-old children with specific language impairment and suggested that these deficits may be a key contributor to LPs (10). In that experiment, we measured tone-detection thresholds in five conditions: a long tone presented during a noise and a brief tone presented before, at the beginning of, toward the middle of, or after that noise.…”

“…Beyond the psychosocial stress experienced by affected individuals and their families, LPs cost society billions of dollars annually in special education services, lost productivity, and un-and underemployment (2). Most current theories of these LPs focus on particular impairments in the neurological (3)(4)(5)(6), perceptual (7)(8)(9)(10), cognitive (11,12), or linguistic (13)(14)(15)(16)(17)(18)(19) functioning of affected individuals. However, few attempts have been made to integrate the wide range of abnormalities seen in these populations (3,15).…”