Monthly Archives: October 2010
A Longitudinal Study of the Effect of Voicing on the Dichotic Listening Ear Advantage in Boys and Girls at Age 5 to 8
Recent studies indicate that the effect of voicing on the ear advantage in dichotic listening might serve as indicator of the development of speech processing abilities in children. In the present longitudinal study, we tested this idea by applying dichotic listening with voiced and unvoiced consonant-vowel syllables. In 35 boys and girls, tested at the age of 5, 6, 7, and 8 years, we found that the effect of voicing increases with age, and that girls were more affected by the voicing characteristics than boys. These results indicate a sex difference in the development of speech processing abilities.
Can Training Normalize Atypical Passive Auditory ERPs in Children with SRD or SLI?
This study tested if training can normalize atypical passive auditory event-related potentials in the N1-P2 time window in children with specific reading disability (SRD) or specific language impairment (SLI). Children with SRD or SLI and untrained controls were tested for their behavioral responses and N1-P2 windows to tones, backward-masked tones, vowels, and consonant-vowels. Children with SRD or SLI with poor behavioral responses to one of these sounds trained to discriminate that sound for 30 minutes a day, 4 days a week, for 6 weeks. Post-training measures revealed that training normalized atypical behavioral responses but not atypical N1-P2 windows.
Cortical Responses to Speech Sounds in 3- and 6-Month-Old Infants Fed Breast Milk, Milk Formula, or Soy Formula
Controversy exists about the safety of soy formula, with the main concern relating to potential estrogenic effects of soy protein. Since estrogens influence early brain development, we compared behavioral development and cortical responses (event-related potentials; ERPs) to speech sounds in infants fed either breast milk or formula (milk- or soy-based). Across-groups ERP measures were generally similar and behavioral measures were within normal ranges, suggesting no important influences of soy formula on behavioral development and brain function during the study period. Analyses relating ERP and behavioral measures revealed diet- and gender-specific emphases that may reflect differences in developmental trajectories of brain-behavior relationships.
Non-Linguistic Auditory Processing and Working Memory Update in Pre-School Children Who Stutter: An Electrophysiological Study
Non-linguistic auditory processing and working memory update were examined with event-related potentials (ERPs) in 18 children who stutter (CWS) and 18 children who do not stutter (CWNS). Children heard frequent 1 kHz tones interspersed with rare 2 kHz tones. The two groups did not differ on any measure of the P1 and N1 components, strongly suggesting that early auditory processing of pure tones is unimpaired in CWS. However, as a group, only CWNS exhibited a P3 component to rare tones, suggesting that developmental stuttering may be associated with a less efficient attentional allocation and working memory update in response to auditory change.
The Specific Role of Inhibition in Reading Comprehension in Good and Poor Comprehenders
Difficulties in inhibitory processes have been shown to characterize the performance of poor comprehenders. However, the inhibitory inefficiency of poor comprehenders is most often assessed by their resistance to proactive interference, that is, the ability to suppress off-goal task information from working memory (WM). In two studies tasks assessing resistance to proactive interference (intrusion errors), response to distracters (Text With Distracters task) and prepotent response inhibition (Stroop and Hayling tests), along with WM measures, were administered to children aged 10 to 11, both good and poor comprehenders. The aim of the study was to specifically determine whether general or specific inhibitory factors affect poor comprehenders’ reading difficulties. Results showed that poor comprehenders, compared to good ones, are impaired in WM tasks and in inhibitory tasks that assess resistance to proactive interference. This suggests that reading comprehension difficulties of poor comprehenders are related to specific inhibitory problems.
from the Journal of Learning Disabilities
Teacher Attitudes Toward Dyslexia: Effects on Teacher Expectations and the Academic Achievement of Students With Dyslexia
The present study examined teacher attitudes toward dyslexia and the effects of these attitudes on teacher expectations and the academic achievement of students with dyslexia compared to students without learning disabilities. The attitudes of 30 regular education teachers toward dyslexia were determined using both an implicit measure and an explicit, self-report measure. Achievement scores for 307 students were also obtained. Implicit teacher attitudes toward dyslexia related to teacher ratings of student achievement on a writing task and also to student achievement on standardized tests of spelling but not math for those students with dyslexia. Self-reported attitudes of the teachers toward dyslexia did not relate to any of the outcome measures. Neither the implicit nor the explicit measures of teacher attitudes related to teacher expectations. The results show implicit attitude measures to be a more valuable predictor of the achievement of students with dyslexia than explicit, self-report attitude measures.
from the Journal of Learning Disabilities
The Role of Morphological Awareness in Reading Comprehension Among Typical and Learning Disabled Native Arabic Speakers
This work examines the role of morphological awareness in contrast to phonological processing in reading comprehension amongst two groups of native Arabic children: a group with learning disabilities (LD) and a mainstream group who were matched to the LD group in age or reading level. Measures of reading comprehension fluency, phonological skills, and morphological ability were given to both groups in addition to tests of nonverbal ability. For the mainstream children, unique variability in comprehension was predicted by the morphological measures over that of the measures of phonological skills and general nonverbal ability. In contrast, for the LD data, variability in comprehension was not predicted by morphological ability even though the children with LD performed the morphology task as well as their typically developing peers did. These findings are discussed in terms of theories of reading acquisition across languages as well as recommendations for literacy teaching and LD intervention in Arabic.
from the Journal of Learning Disabilities
Content and Procedural Learning in Repeated Sentence Tests of Speech Perception
Conclusions: Both the HINT and the QuickSIN provide stable and sensitive measures of speech perception across repeated test sessions provided that sentences are not repeated. Practice with at least two sentence lists is needed to eliminate the initial effect of procedural learning in the first session. The results with the HINT and QuickSIN at moderate noise levels differ from previous results of sentence testing in quiet, whereas SRTs improved 6 to 9 dB over five sessions for both repeated and unique sentences. Differences between testing at moderate noise levels and in quiet seem to account for the difference in the stability of these sentence-test measurements.
from Ear and Hearing
Development of the ORCA Nonsense Syllable Test
Conclusions: The current nonsense syllable test provided a reliable and efficient means for phoneme identification testing.
from Ear and Hearing
Effect of Varying Phase Between Frequency and Amplitude Modulation on Bone Conduction Auditory Steady State Responses
Conclusions: Different stimuli can significantly affect the amplitudes of bone conduction ASSRs. These effects are similar to those observed for air conduction ASSRs. MM stimuli with specific phase settings evoke larger bone conduction ASSRs compared with AM and FM stimuli alone, and calculations show that the time taken to obtain these responses is reduced. Implementation of the suggested optimum settings will promote efficient collection of bone conduction, and indeed air conduction, ASSR data.
from Ear and Hearing
Hearing History Influences Voice Gender Perceptual Performance in Cochlear Implant Users
Conclusions: The existence of a group of subjects able to perform adaptive discrimination but unable to identify the gender of singly presented voices demonstrates the potential dissociability of the skills required for these two tasks, suggesting that duration of deafness and age of cochlear implantation could have dissociable effects on the development of different skills required by CI users to identify speaker gender.
from Ear and Hearing
Maturation of Speech Discrimination in 4- to 7-Yr-Old Children as Indexed by Event-Related Potential Mismatch Responses
Conclusions: Maturation of speech discrimination, as indexed by MMN, occurs more rapidly between 4 and 7 yrs of age for vowels than for tones. A p-MMR preceding the MMN also reflects discrimination in younger children and declines in amplitude with age.
from Ear and Hearing
Processing of Temporal Fine Structure as a Function of Age
Conclusions: These results suggest that deficits in temporal fine structure processing are evident in the presenescent auditory system. This adds to the accumulating evidence that deficiencies in some aspects of auditory temporal processing emerge relatively early in the aging process. It is possible that early-emerging temporal processing deficits manifest themselves in challenging speech in noise environments.
from Ear and Hearing
Psychoacoustic Abilities Associated With Music Perception in Cochlear Implant Users
Conclusions: This study suggests that spectral-ripple discrimination is significantly associated with music perception in CI users. A previous report showed that spectral-ripple discrimination is significantly correlated with speech recognition in quiet and in noise. This study also showed that speech recognition and music perception are also related to one another. Spectral-ripple discrimination ability seems to reflect a wide range of hearing abilities in CI users. The results suggest that materially improving spectral resolution could provide significant benefits in music and speech perception outcomes in CI users.
from Ear and Hearing
Relationship Between Speech Perception in Noise and Phonological Awareness Skills for Children With Normal Hearing
Conclusions: Although phonological awareness skills are strongly related to reading and some children with reading difficulties also demonstrate poor speech perception in noise, results of this study question a relation between phonological awareness skills and speech perception in moderate levels of noise for typically developing children with normal hearing from 5 to 7 yrs of age. Further research in this area is needed to examine possible relations among the many factors that affect both speech perception in noise and the development of phonological awareness.
from Ear and Hearing
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