Auditory Temporal Processing in Disabled Readers With and Without Oral Language Delay

Abstract

Inferior auditory temporal processing has been postulated as causally linked to phonological processing deficits in disabled readers with concomitant oral language delay (LDRDs), and absent in specifically disabled readers with normal oral language (SRDs). This investigation compared SRDs, LDRDs and normal readers aged 7-10 years on measures of auditory temporal processing (temporal order judgement) and phonological decoding (nonword reading). LDRDs exhibited deficits in temporal order judgement compared with normal readers, from whom SRDs did not differ significantly. These findings suggest that auditory temporal processing and oral language are related; however, very large within-group variability in the auditory temporal processing data further suggests that this relationship prevails in only a proportion of disabled readers with concomitant oral language weakness. In nonword reading, LDRDs performed worst of all, but SRDs also exhibited significant deficits compared with normal readers. Taken together, our results preclude the conceptualisation of temporal processing deficits as the unitary cause of phonological and language deficits in disabled readers.

Specific reading disability (dyslexia): what have we learned in the past four decades?

“…Breier et al (2002) specifically excluded children with oral language difficulties. Moreover, Heath et al (1999) also found nonspeech auditory processing deficits in only those poor readers with concomitant oral language difficulties and not those poor readers without oral language difficulties. Both Waber et al (2001) and Breier et al (2002) concluded that children with dyslexia have difficulties with speech perception that produce deficits on temporal processing tests, but do not have a pervasive deficit in auditory temporal processing.…”

“…Noteworthy is the observation that reader group differences in these studies tended to be more reliable in contrasts involving more severely impaired readers, suggesting that basic deficits in speech perception and production may underlie phonological skills deficiencies in only some poor readers (Heath, Hogben, & Clark, 1999). This pattern of results suggests that deficiencies in phonological skills such as phonological awareness and letter-sound decoding may, in some children, be caused by factors other than basic deficits in speech perception and/or production, such as inadequate instruction and experience.…”

Patterns of deficit in auditory temporal processing among dyslexic adults

“…These classifications are not independent of general cognitive abilities, since dyslexics with language difficulties and also had lower cognitive scores (e.g. verbal IQ of dyslexics with oral language delay was 88.3 [12], lower than that of other subtypes). Consistent with associating lower cognitive abilities with poorer perceptual performance, Banai and Ahissar [13] found that a subgroup of adult dyslexics characterized by poor frequency discrimination (measured with an ISI of B1 s) also scored poorly on a standard cognitive test (Raven's Matrices [14]).…”

“…However, it is difficult to divide dyslexics to those with and without phonetic deficits, since most have both [1]. Another classification is based on co-morbidity of reading difficulties with other learning disorders, such as an oral language delay [12]. Indeed, several studies suggested that temporal processing deficits are found only among dyslexics with concomitant language disorders [12].…”

“…Another classification is based on co-morbidity of reading difficulties with other learning disorders, such as an oral language delay [12]. Indeed, several studies suggested that temporal processing deficits are found only among dyslexics with concomitant language disorders [12]. These classifications are not independent of general cognitive abilities, since dyslexics with language difficulties and also had lower cognitive scores (e.g.…”