The Role of Temporal and Phonological Processing In Early Reading Development: A Longitudinal Study

What is the Role of Audition in Literacy?

This study investigated the ability of temporal processing measures obtained before school entry to predict early reading development in an unselected sample of 125 children (68 males, 57 females). Visual and auditory temporal order judgement (TOJ) tasks measured at Preschool (mean age 5.36 years) significantly predicted letter and word identification (accuracy) and reading rate (fluency) in early Grade 1 (mean age 5.94 years), even after the effects of age, environment, memory, attention, nonverbal ability, and speech/language problems were accounted for. There were no significant differences in the overall variance accounted for in reading between TOJ measures taken before or after reading had emerged. Both Preschool and Grade 1 measures of auditory TOJ accounted for significant independent variance in reading. However, only visual TOJ performance measured at Grade 1 accounted for unique variance in reading rate. This was discussed in terms of developmental changes in the role of visual temporal processing as reading develops. Reliability of the temporal measures from Preschool to Grade 1 was moderate. The results showed that measures of visual and auditory temporal processing obtained close to school-entry would be a useful addition to predicting risk of early reading difficulties.

This study examined the extent to which Chinese children with dyslexia show temporal processing deficits in addition to deficits in various forms of attention. In total, 104 Chinese children in primary school (Grades 3–6) were recruited in Taiwan. Half of the children were identified as having dyslexia, and the other half were typically developing children who were matched by gender, IQ, and age with the children with dyslexia. Our results indicated that Chinese children with dyslexia performed significantly worse on tasks of temporal processing, selective attention, and switching attention. Furthermore, both visual and auditory temporal processing, in addition to various attention types, could be significant distinguishing predictors between the two groups. Moreover, we found that visual temporal processing, but not auditory temporal processing, significantly contributed to Chinese character reading. This study was among the first to confirm the unique role of visual temporal processing in Chinese character reading.

Neural correlates of temporal auditory processing in developmental dyslexia during German vowel length discrimination: An fMRI study

In the present study, the role of rapid visual and auditory temporal processing in reading irregular and nonsense words was investigated with a group of normal readers. One hundred and five undergraduates participated in various visual and auditory temporal-processing tasks. Readers who primarily adopted the phonological route in reading (nonsense-word readers) showed a trend for better auditory temporal resolution but readers who primarily adopted sight word skills (irregular-word readers) did not exhibit better visual temporal resolution. Both the correlation and stepwise multiple-regression analyses, however, revealed a relationship between visual temporal processing and irregular-word reading as well as a relationship between auditory temporal processing and nonsense-word reading. The results support the involvement of visual and auditory processing in reading irregular and nonsense words respectively, and were discussed with respect to recent findings that only dyslexics with phonological impairment will display temporal deficits. Further, the temporal measures were not effective discriminants for the reading groups, suggesting a lack of association between reading ability and the choice of reading strategy.

The ability to understand speech in complex environments depends on the brain’s ability to preserve the precise timing characteristics of the speech signal. Age-related declines in temporal processing may contribute to the older adult’s experience of communication difficulty in challenging listening conditions. This study’s purpose was to evaluate the effects of rate discrimination training on auditory temporal processing. A double-blind, randomized control design assigned 77 young normal-hearing, older normal-hearing, and older hearing-impaired listeners to one of two treatment groups: experimental (rate discrimination for 100- and 300-Hz pulse trains) and active control (tone detection in noise). All listeners were evaluated during pre- and post-training sessions using perceptual rate discrimination of 100-, 200-, 300-, and 400-Hz band-limited pulse trains and auditory steady-state responses (ASSRs) to the same stimuli. Training generalization was evaluated using several temporal processing measures and sentence recognition tests that included time-compressed and reverberant speech stimuli. Results demonstrated a session × training group interaction for perceptual and ASSR testing to the trained frequencies (100 and 300 Hz), driven by greater improvements in the training group than in the active control group. Further, post-test rate discrimination of the older listeners reached levels that were equivalent to those of the younger listeners at pre-test. Generalization was observed in significant improvement in rate discrimination of untrained frequencies (200 and 400 Hz) and in correlations between performance changes in rate discrimination and sentence recognition of reverberant speech. Further, non-auditory inhibition/attention performance predicted training-related improvement in rate discrimination. Overall, the results demonstrate the potential for auditory training to partially restore temporal processing in older listeners and highlight the role of cognitive function in these gains.

Background. Understanding the factors that influence language recovery in aphasia is important for improving prognosis and treatment. Chronic comprehension impairments in Wernicke’s aphasia (WA) are associated with impairments in auditory and phonological processing, compounded by semantic and executive difficulties. This study investigated whether the recovery of auditory, phonological, semantic, or executive factors underpins the recovery from WA comprehension impairments by charting changes in the neuropsychological profile from the subacute to the chronic phase. Method. This study used a prospective, longitudinal observational design. Twelve WA participants with superior temporal lobe lesions were recruited 2 months post–stroke onset (2 MPO). Language comprehension was measured alongside a neuropsychological profile of auditory, phonological, and semantic processing and phonological short-term memory and nonverbal reasoning at 3 poststroke time points: 2.5, 5, and 9 MPO. Results. Language comprehension displayed a strong and consistent recovery between 2.5 and 9 MPO. Improvements were also seen for slow auditory temporal processing, phonological short-term memory, and semantic processing but not for rapid auditory temporal, spectrotemporal, and phonological processing. Despite their lack of improvement, rapid auditory temporal processing at 2.5 MPO and phonological processing at 5 MPO predicated comprehension outcomes at 9 MPO. Conclusions. These results indicate that recovery of language comprehension in WA can be predicted from fixed auditory processing in the subacute stage. This suggests that speech comprehension recovery in WA results from reorganization of the remaining language comprehension network to enable the residual speech signal to be processed more efficiently, rather than partial recovery of underlying auditory, phonological, or semantic processing abilities.

The relationships among visual and auditory temporal processing, rapid naming, and oral reading fluency in Chinese children with and without dyslexia were examined. Primary school-aged Chinese children with dyslexia ( N = 47) and chronological-age-matched controls ( N = 47) were recruited. Temporal processing, rapid naming, oral reading fluency, Chinese character reading, and nonverbal IQ were assessed. There were significant correlations among visual and auditory temporal processing, rapid naming, and oral reading fluency. The patterns of the relationships among these measures differed between the children with and without dyslexia. The path analyses revealed that visual temporal processing had significant direct and indirect effects (through rapid naming) on oral reading fluency; only the children with dyslexia showed a significant direct effect of auditory temporal processing. These findings have research and educational implications for enhancing the reading abilities of Chinese children with dyslexia.

The hypothesis of a general (i.e. cross-modal) temporal processing deficit in dyslexia was tested by examining rapid processing in both the auditory and the visual system in the same children with dyslexia. Participants were 10- to 12-year-old dyslexic readers and age-matched normal reading controls. Psychophysical thresholds were estimated for auditory gap and visual double flash detection, using a two-interval, two-alternative forced-choice paradigm. Significant group differences were found for the auditory and the visual test. Furthermore, temporal processing measures were significantly related to word and pseudo-word reading skills. As 70% of the dyslexic readers had significantly higher thresholds than controls for both auditory and visual temporal processing, the evidence tends to support the hypothesis of a general temporal processing deficit in children with dyslexia.

In this study, we examined whether good auditory and good visual temporal processors were better than their poor counterparts on certain reading measures. Various visual and auditory temporal tasks were administered to 105 undergraduates. They read some phonologically regular pseudowords and irregular words that were presented sequentially in the same ("word" condition) and in different ("line" condition) locations. Results indicated that auditory temporal acuity was more relevant to reading, whereas visual temporal acuity was more relevant to spelling. Good auditory temporal processors did not have the advantage in processing pseudowords, even though pseudoword reading correlated significantly with auditory temporal processing. These results suggested that some higher cognitive or phonological processes mediated the relationship between auditory temporal processing and pseudoword reading. Good visual temporal processors did not have the advantage in processing irregular words. They also did not process the line condition more accurately than the word condition. The discrepancy might be attributed to the use of normal adults and the unnatural reading situation that did not fully capture the function of the visual temporal processes. The distributions of auditory and visual temporal processing abilities were co-occurring to some degree, but they maintained considerable independence. There was also a lack of a relationship between the type and severity of reading deficits and the type and number of temporal deficits.

BackgroundAutism spectrum disorders (ASD) encompass a wide array of debilitating symptoms, including sensory dysfunction and delayed language development. Auditory temporal processing is crucial for speech perception and language development. Abnormal development of temporal processing may account for the language impairments associated with ASD. Very little is known about the development of temporal processing in any animal model of ASD.MethodsIn the current study, we quantify auditory temporal processing throughout development in the Fmr1 knock-out (KO) mouse model of Fragile X Syndrome (FXS), a leading genetic cause of intellectual disability and ASD-associated behaviors. Using epidural electrodes in awake and freely moving wildtype (WT) and KO mice, we recorded auditory event related potentials (ERP) and auditory temporal processing with a gap-in-noise auditory steady state response (gap-ASSR) paradigm. Mice were recorded at three different ages in a cross sectional design: postnatal (p)21, p30 and p60. Recordings were obtained from both auditory and frontal cortices. The gap-ASSR requires underlying neural generators to synchronize responses to gaps of different widths embedded in noise, providing an objective measure of temporal processing across genotypes and age groups.ResultsWe present evidence that the frontal, but not auditory, cortex shows significant temporal processing deficits at p21 and p30, with poor ability to phase lock to rapid gaps in noise. Temporal processing was similar in both genotypes in adult mice. ERP amplitudes were larger in Fmr1 KO mice in both auditory and frontal cortex, consistent with ERP data in humans with FXS.ConclusionsThese data indicate cortical region-specific delays in temporal processing development in Fmr1 KO mice. Developmental delays in the ability of frontal cortex to follow rapid changes in sounds may shape language delays in FXS, and more broadly in ASD.

Older adults have more difficulty than younger adults understanding speech when there is competing speech, even if they have good audiograms. Age-related differences in listening may be due to declines in auditory temporal processing and/or cognition. We administered the LiSN-S (Cameron et al., 2011) to measure speech reception thresholds (SRTs) in younger and older adults with good audiograms. There were four test conditions, in which the target and competing speech were presented with the same or different voices at the same or different locations. Compared to younger listeners, older listeners obtained worse SRTs in all test conditions and they realized less advantage from talker differences and spatial separation between the target and competing speech. For both groups, the results obtained in the four test conditions were strongly associated with each other. We also assessed cognitive abilities and auditory temporal processing in the older adults. LiSN-S results in this group were strongly associated with measures of cognition, as well as pure-tone averages (PTA) for 9 and 10 kHz, but not PTAs for frequencies in the standard audiometric range or measures of temporal processing (tapping the use of fine structure and gap cues).

Older adults have more difficulty than younger adults understanding speech when there is competing speech, even if they have good audiograms. Age-related differences in listening may be due to declines in auditory temporal processing and/or cognition. We administered the LiSN-S [Cameron et al. (2011)] to measure speech reception thresholds (SRTs) in younger and older adults with good audiograms. There were four test conditions, in which the target and competing speech were presented with the same or different voices at the same or different locations. Compared to younger listeners, older listeners obtained worse SRTs in all test conditions and they realized less advantage from talker differences and spatial separation between the target and competing speech. For both groups, the results obtained in the four test conditions were strongly associated with each other. We also assessed cognitive abilities and auditory temporal processing in the older adults. LiSN-S results in this group were strongly associated with measures of cognition, measures of temporal processing (tapping the use of fine structure and gap cues), as well as pure-tone averages (PTA) for 9 and 10 kHz, but not PTAs for frequencies in the standard audiometric range.

This study examined whether rapid temporal auditory processing, verbal working memory capacity, non-verbal intelligence, executive functioning, musical ability and prior foreign language experience predicted how well native English speakers (N = 120) discriminated Norwegian tonal and vowel contrasts as well as a non-speech analogue of the tonal contrast and a native vowel contrast presented over noise. Results confirmed a male advantage for temporal and tonal processing, and also revealed that temporal processing was associated with both non-verbal intelligence and speech processing. In contrast, effects of musical ability on non-native speech-sound processing and of inhibitory control on vowel discrimination were not mediated by temporal processing. These results suggest that individual differences in non-native speech-sound processing are to some extent determined by temporal auditory processing ability, in which males perform better, but are also determined by a host of other abilities that are deployed flexibly depending on the characteristics of the target sounds.

This study aimed to examine the effects of temporal processing training on the reading abilities of Chinese children with dyslexia. In total, 69 Chinese children with dyslexia in grades three through six were recruited in Taiwan. The children were divided into the following three equal groups: (1) auditory temporal processing training group, (2) visual temporal processing training group, and (3) control group with no specific training. The participants in both training groups received instruction with identical durations (30-40min), intensities (12 times in total), and frequencies (three to four times per week). The participants in the control group were asked to independently surf some specified websites using devices similar to those used by the two experimental groups for an identical duration, intensity, and frequency. Our results indicated that the two groups who received temporal processing training exhibited significant correlations among Chinese character reading, rapid naming, and corresponding reading-related abilities, while visual temporal processing served as a significant predictor of Chinese character reading ability even if all background data, reading-related abilities, and auditory temporal processing were introduced first. Additionally, significant interactions were found between the Groups and Tested sessions in all the measures, except for phonological awareness, confirming the distinct effects of different temporal processing on most measures involved in this study. Further simple main effects revealed that only those who received the visual temporal processing training gained benefits in the corresponding reading-related ability (i.e., orthographic knowledge) and far-transfer to Chinese character reading.