Auditory temporal processing, reading, and phonological awareness among aging adults

This study addressed 2 questions: (a) Can preschoolers who will fail at reading be more efficiently identified by targeting those at highest risk for reading problems? and (b) will auditory temporal processing (ATP) improve the accuracy of identification derived from phonological processing and oral language ability? A sample of 227 preschoolers was screened for Performance IQ and was tested on phonological awareness (PA). The upper and lower quartiles of the PA distribution were selected as being at lowest and highest risk, respectively, for reading failure. Children with good and poor PA were tested on ATP, phonological short-term memory, rapid automatized naming, oral language, receptive vocabulary, and 2 measures of listening comprehension. Reading outcomes were measured at the end of Year 2. Only 1 child in the good-PA group became a poor reader by the end of Year 2, confirming that being in the top quartile for PA predicts positive reading outcomes. Discriminant analysis using the authors' test battery within the poor-PA group identified poor readers with sensitivity of.91 and specificity of.84, but ATP did not improve classification accuracy afforded by phonological and oral language. A brief screening procedure was formulated using only PA, phonological short-term memory, and demographic variables, with which 80% of children with poor PA who are at risk of reading problems can be identified. Further refinements of this screening procedure would increase accuracy of identification at the cost of only a small increment in required testing time.

Dyslexia as a multi-deficit disorder: Working memory and auditory temporal processing

The nature and cause of auditory processing deficits in dyslexic individuals have been debated for decades. Auditory processing deficits were argued to be the first step in a causal chain of difficulties, leading to difficulties in speech perception and thereby phonological processing and literacy difficulties. More recently, it has been argued that auditory processing difficulties may not be causally related to language and literacy difficulties. This study compares two groups who have phonological processing impairments for different reasons: dyslexia and a history of otitis media (OM). We compared their discrimination thresholds and response variability to chronological age- and reading age-matched controls, across three auditory processing tasks: frequency discrimination, rise-time discrimination and speech perception. Dyslexic children showed raised frequency discrimination thresholds in comparison with age-matched controls but did not differ from reading age-matched controls or individuals with a history of OM. There were no group differences on speech perception or rise-time tasks. For the dyslexic children, there was an association between phonological awareness and frequency discrimination response variability, but no association with thresholds. These findings are not consistent with a 'causal chain' explanation but could be accounted for within a multiple deficits view of literacy difficulties.

Background and Aim: Many older adults experience difficulty in speech perception in noisy environments and fast speech. Speech perception is dependent on bottom-up and top-down auditory processing information. This study aimed to investigate the relationship between Interaural Time Difference (ITD) and speech processing speed in older adults with difficulty in speech perception in noise. Methods: In this study, 36 Iranian older adults with normal hearing (23 men and 13 women) aged 65–75 years who had complaints about the difficulty with speech perception in noise, participated. The ITD test with two stimuli (high-pass and low-pass noise) was used to asess the auditory localization ability. Time-Compressed Speech Test (TCST) and reaction time test were used to measure their speech processing speed. Pearson correlation test was performed to examine the relationship between ITD and speech processing speed. Results: The auditory localization errors were more significant for ITDs with low-pass noise than high-pass noise. The results showed a negative correlation between localization errors and the TCST score at time compression ratios of 40% (p=0.005) and 60% (p=0.002). The highest correlation was observed between ITD (low-pass noise) and the TCST score at the time compression ratio of 60% in the right ear (r=–0.66). The mean ITD errors were not significantly correlated to the reaction time test score (p>0.05). Conclusion: Word recognition in the elderly declines with increasing speech rate. The findings of this study can be used in clinical practice for consultation and rehabilitation of older adults with communication difficulties. Keywords: Sound localization; speed processing; speech perception; elderly

Preschool impairments in auditory processing and speech perception uniquely predict future reading problems

Speech production difficulties are apparent in people who stutter (PWS). PWS also have difficulties in speech perception compared to controls. It is unclear whether the speech perception difficulties in PWS are independent of, or related to, their speech production difficulties. To investigate this issue, functional MRI data were collected on 13 PWS and 13 controls whilst the participants performed a speech production task and a speech perception task. PWS performed poorer than controls in the perception task and the poorer performance was associated with a functional activity difference in the left anterior insula (part of the speech motor area) compared to controls. PWS also showed a functional activity difference in this and the surrounding area [left inferior frontal cortex (IFC)/anterior insula] in the production task compared to controls. Conjunction analysis showed that the functional activity differences between PWS and controls in the left IFC/anterior insula coincided across the perception and production tasks. Furthermore, Granger Causality Analysis on the resting-state fMRI data of the participants showed that the causal connection from the left IFC/anterior insula to an area in the left primary auditory cortex (Heschl’s gyrus) differed significantly between PWS and controls. The strength of this connection correlated significantly with performance in the perception task. These results suggest that speech perception difficulties in PWS are associated with anomalous functional activity in the speech motor area, and the altered functional connectivity from this area to the auditory area plays a role in the speech perception difficulties of PWS.

People suffering from age-related hearing loss typically present with deficits in temporal processing tasks. Temporal processing deficits have also been shown in single-unit studies at the level of the auditory brainstem, midbrain, and cortex of aged animals. In this study, we explored whether temporal coding is already affected at the level of the input to the central auditory system. Single-unit auditory nerve fiber recordings were obtained from 41 Mongolian gerbils of either sex, divided between young, middle-aged, and old gerbils. Temporal coding quality was evaluated as vector strength in response to tones at best frequency, and by constructing shuffled and cross-stimulus autocorrelograms, and reverse correlations, from responses to 1 s noise bursts at 10-30 dB sensation level (dB above threshold). At comparable sensation levels, all measures showed that temporal coding was not altered in auditory nerve fibers of aging gerbils. Furthermore, both temporal fine structure and envelope coding remained unaffected. However, spontaneous rates were decreased in aging gerbils. Importantly, despite elevated pure tone thresholds, the frequency tuning of auditory nerve fibers was not affected. These results suggest that age-related temporal coding deficits arise more centrally, possibly due to a loss of auditory nerve fibers (or their peripheral synapses) but not due to qualitative changes in the responses of remaining auditory nerve fibers. The reduced spontaneous rate and elevated thresholds, but normal frequency tuning, of aged auditory nerve fibers can be explained by the well known reduction of endocochlear potential due to strial dysfunction in aged gerbils.SIGNIFICANCE STATEMENT As our society ages, age-related hearing deficits become ever more prevalent. Apart from decreased hearing sensitivity, elderly people often suffer from a reduced ability to communicate in daily settings, which is thought to be caused by known age-related deficits in auditory temporal processing. The current study demonstrated, using several different stimuli and analysis techniques, that these putative temporal processing deficits are not apparent in responses of single-unit auditory nerve fibers of quiet-aged gerbils. This suggests that age-related temporal processing deficits may develop more central to the auditory nerve, possibly due to a reduced population of active auditory nerve fibers, which will be of importance for the development of treatments for age-related hearing disorders.

Auditory processing and speech perception in children with specific language impairment: Relations with oral language and literacy skills

Introduction. Developmental coordination disorder is a disorder of planning and coordination of complex movements during action, without previously diagnosed intellectual disability, neurological or any other sensory impairment. Although it is a relatively common disorder in school-age population, the correlation between phonological awareness and spelling in these children has not been sufficiently investigated. Objective. The aim of this study was to determine the relationship between phonological awareness and spelling in children with developmental coordination disorder compared to children without coordination difficulty. Methods. The research included 65 children of the third grade of primary schools in Belgrade. Developmental coordination disorder was observed in 29 children, while 36 children did not have this disorder. The Questionnaire for Developmental Coordination Disorder was used to determine its presence. Phonological awareness was assessed by the Test of Phonological Awareness, and spelling by dictation. Results. The results show significant below-average achievements in the assessment of phonological awareness and spelling in children with developmental coordination disorder. Phonemic substitution was the least developed element of phonological awareness. The largest number of errors was observed at the word level, while substitution was the most common error at the syllabic and letter level. A positive correlation between phonemic segments and achievements in spelling indicates a relationship between the sublexical level and spelling development. Conclusion. Poor phonological awareness and spelling ability lead to learning disabilities during the educational process, which results in an overall poorer educational achievement in these children.

Introduction: Reading impairment in children with dyslexia stems from either a phonological awareness deficit or a deficit in rapid automatized naming. Both deficits constitute the double deficit hypothesis of dyslexia. The aim of the present study was to assess phonological awareness and rapid automatized naming in a group of Greek-speaking children with dyslexia and to correlate their performance in phonological awareness and rapid automatized naming with reading fluency (accuracy and comprehension) scores. Method: Participants were 23 children with a formal diagnosis of dyslexia and 27 typically-developing children with no other learning difficulties or dyslexia. All children were monolingual speakers of Greek and they were administered a naming speed test, a fluency test, a phonological awareness test and reading accuracy and comprehension tasks. Results: Students with dyslexia scored worse in most phonological awareness, rapid automatized naming and reading fluency measures in comparison to their non-dyslexic peers. In addition, students with dyslexia needed more time to complete the rapid automatized naming tests. Positive correlations were found between phonological awareness, rapid automatized naming and reading fluency tests for both groups of students. Specifically, rapid automatized naming and phonological awareness explained 9.3% and 21.8%, respectively, of the variance in the reading fluency of students with dyslexia, while the respective contributions of rapid automatized naming and phonological awareness to the reading fluency for non-dyslexic students were 2% and 9.3%, respectively. Discussion and Conclusion: Phonological awareness and rapid automatized naming can be reliable predictors of reading fluency even in orthographically consistent languages (i.e., Greek), offering support to the double deficit hypothesis. In addition, combining phonological awareness and rapid automatized naming tests seems to be a quick and reliable way to early identify children at risk of reading difficulties in the first grades of primary school.

This paper examines frequency selectivity in hearing-impaired listeners and discusses some of the implications of reduced frequency selectivity in these listeners. Different measures of frequency selectivity were examined in three diagnostic groups: otosclerotic, noise-induced, and degenerative. Frequency selectivity, whether measured by psychoacoustical tuning curves, narrow-band masking, two-tone masking, or loudness summation, was reduced only in the frequency region of a nonconductive impairment. The results across the four measures were significantly correlated and reduced frequency selectivity was positively correlated with the amount of impairment. The implications of reduced frequency selectivity are discussed briefly with regard to alterations in the loudness of complex sounds and impaired speech perception. The present masking measurements provide a basis for modifying Zwicker's [Acustica 8, 237–258 (1958)] model of loudness summation to apply to cochlear impairment. When the presence of recruitment, upward spread of masking, and enlarged critical bands are incorporated into the model, predictions of the model show reasonable agreement with loudness-summation data. Furthermore, cochlearly impaired listeners' difficulty in speech perception may be better understood by considering the increased spread of masking and the blurring of formants falling within the same enlarged critical band. [Work supported by NIH and NSF.]

Background and ObjectivesA deficit in phonological processing abilities has been hypothesized as a cause of reading deficits among poor readers, but the precise etiology of this deficit is still unknown. Many studies have investigated the relation of auditory processing and speech perception with phonological processing, while the relation between these are not well understood. Thus, the present study was carried out to investigate the relation between these abilities among poor readers.Subjects and MethodsA total of 20 children between 7-12 years of age participated in the study. Among these 10 were typically developing children and 10 were poor readers. Auditory processing, speech perception in noise and phonological processing skills were assessed in both the groups.ResultsAuditory processing was not significantly different between children in both the groups. In contrast, phonological awareness, verbal short-term memory and rapid automatized naming, which reflect phonological processing, and speech perception in noise were found to be significantly affected in poor readers. In addition, the results showed a significant correlation between phonological processing and speech perception in noise.ConclusionsThe present study found a significant relationship between speech perception in noise and phonological processing, while there was no relationship between auditory processing and phonological processing. This finding suggests that poor speech perception among poor readers may be one of the contributing factors for phonological processing deficits, which in turn leads to reading difficulties.

Although children with speech disorder are at increased risk of literacy impairments, many learn to read and spell without difficulty. They are also a heterogeneous population in terms of the number and type of speech errors and their identified speech processing deficits. One problem lies in determining which preschool children with speech disorder will have difficulties acquiring literacy skills. Two studies are presented that investigate the relationship between speech disorders and literacy. The first examined the phonological awareness abilities of children with different types of speech difficulties. The second study investigated the literacy skills of children with a history of inconsistent speech disorder. Experiment 1 measured the syllable segmentation, rhyme awareness and alliteration awareness of 61 preschool children: 46 with speech disorder (14 with delayed development, 17 who made consistent non-developmental errors, and 15 who made inconsistent errors) and 15 typically developing controls. Experiment 2 assessed the reading accuracy, spelling and phonological awareness abilities of nine 7-year-old children with a history of inconsistent phonological errors. The first study indicated unexpected patterns of performance. While the Delayed group performed less well than controls on all tasks, the Consistent group showed poor performance on rhyme and alliteration but appropriate performance on syllable segmentation. The Inconsistent group performed most poorly on syllable segmentation but no differently from controls on the other two tasks. The second study indicated that children with a history of inconsistent phonological disorder performed no differently from controls on measures of phonological awareness and reading, but less well on measures of spelling ability. The results support classification of speech disorders and show a differentiation of phonological awareness skills across groups. Children with consistent atypical speech errors have poor phonological awareness and are most at risk for literacy difficulties. Those with inconsistent phonological disorder are at increased risk of spelling difficulties. The findings indicate that phonological awareness and spelling skill are distinct processing systems and highlight the role of phonological assembly skills (i.e. storing and/or retrieving phonological output plans) in spelling output. The interactive processes between reading and spelling are discussed.

Differential cognitive and perceptual correlates of print reading versus braille reading

Object: Selective auditory attention and speech perception in the presence of noise are necessary skills to correctly process speech. Persian version of monaural selective auditory attention test [P-mSAAT] that simultaneously assesses selective auditory attention and speech in noise perception performance was used in the present study.Design: The P-mSAAT was performed on 89 normal children aged 6 to 9 and 24 children with learning disability sampled from different schools in Tehran in two competitive and non-competitive ways.Results: The average of test scores had a significant difference in a competitive way between normal and children with learning disability (P < 0/001). Furthermore, the test scores improved as a function of age in the both groups.Conclusion: Findings of the current study demonstrated that children presented with learning disability had difficulty in speech perception in the presence of competitive noise accompanied by reduced selective auditory attention ability. It is also suggested that P-mSAAT can be used as a screening test in diagnosing Learning disability in children aged 6 to 9 due to its high sensitivity.