Monthly Archives: October 2010
The Effectiveness of Using Communication-Centered Intervention to Facilitate Phonological Learning in Young Children
Treatment of preschool children with moderate to severe speech sound disorders is typically a long-term endeavor with many sounds and sound patterns requiring intervention. The purpose of this study was to determine if a communication-centered intervention would be effective in improving speech production with this population. The intervention consisted of the combined application of focused stimulation of key words during joint storybook reading and interactive practice of key words using communicative feedback. Participants displayed unique response patterns to the intervention. Two of the three participants demonstrated improvement in the use of the target speech pattern during intervention sessions, with one of the participants demonstrating generalization of the target pattern to conversational speech. Although the third participant did not demonstrate improvement during the intervention period, follow-up testing revealed some systemwide changes in his phonological system. This study provides preliminary support that communication-centered approaches are effective in facilitating phonological change.
Skin reactions following BAHA surgery using the skin flap dermatome technique
The objectives of the study were to determine the incidence of skin reactions and complications associated with bone-anchored hearing aid (BAHA) implantation. The study is a retrospective case review done in a tertiary referral center. One hundred thirty-eight consecutive patients between 1998 and 2008 underwent implantation of a BAHA and were regularly seen for follow-up. Indications included conductive or mixed hearing loss where a hearing aid cannot be used and since 2000 also had contralateral single-sided perceptive hearing loss. BAHA implantation was done by creating a pedicled flap using the skin flap dermatome technique. Postoperative incidence of skin reactions and complications were measured. Significant postoperative complications requiring revision surgery occurred 37 times in 30 patients. Normal skin healing was seen in 52 patients (63.4%), while abnormal skin healing occurred in 30 patients (36.6%). This study showed that skin problems occur more often than expected. Because of the skin problems with the skin flap technique, the authors have switched to the linear incision technique, hoping to decrease the incidence of skin problems.
Children with Reading Disability Show Brain Differences in Effective Connectivity for Visual, but Not Auditory Word Comprehension
Previous literature suggests that those with reading disability (RD) have more pronounced deficits during semantic processing in reading as compared to listening comprehension. This discrepancy has been supported by recent neuroimaging studies showing abnormal activity in RD during semantic processing in the visual but not in the auditory modality. Whether effective connectivity between brain regions in RD could also show this pattern of discrepancy has not been investigated.
from PLoS ONE
The Hypothesis of Apraxia of Speech in Children with Autism Spectrum Disorder
In a sample of 46 children aged 4–7 years with Autism Spectrum Disorder (ASD) and intelligible speech, there was no statistical support for the hypothesis of concomitant Childhood Apraxia of Speech (CAS). Perceptual and acoustic measures of participants’ speech, prosody, and voice were compared with data from 40 typically-developing children, 13 preschool children with Speech Delay, and 15 participants aged 5–49 years with CAS in neurogenetic disorders. Speech Delay and Speech Errors, respectively, were modestly and substantially more prevalent in participants with ASD than reported population estimates. Double dissociations in speech, prosody, and voice impairments in ASD were interpreted as consistent with a speech attunement framework, rather than with the motor speech impairments that define CAS.
Subjective and objective outcomes of tympanoplasty surgery at National Hospital Abuja, Nigeria 2005–2009
The objective of this study is to determine the subjective and objective outcomes of tympanoplasty surgery carried out in patients with otitis media and to identify factors responsible for these outcomes. The study setting is tertiary care urban referral hospital in a developing economy and the study methodology is a prospective analysis of patients with diagnosis of chronic suppurative otitis media that had tympanoplasty with or without mastoidectomy between May 2005 and September 2009 at National Hospital Abuja. Subjects were evaluated for age, sex, size and site of perforation, status of operated ear(s) (dry/discharging), status of the contralateral ear, surgical technique, subjective and objective pre-operative and post-operative hearing scores, average post-operative follow-up time, and post-operative complications, and results were statistically analyzed. A total of 45 patients (51 ears) were operated. Age distribution was 8–52 years. Type 1 tympanoplasty was done in 41 patients and Type 3 in 4 patients. Seven of the patient had concomitant mastoid surgery (cortical mastoidectomy). 3/51 of the cases had discharging ears at surgery. 16/45 of the patients (19/51 ears) had cartilage graft tympanoplasty, while 29/45 (32 ears) had temporalis fascia tympanoplasty. 15/16 of the cartilage group as well as 26/29 of the fascia group reported subjective hearing improvement, whilst the actual graft take was 12/16 of the cartilage group and 23/29 of the fascia group. Objective hearing improvement was observed in all of the cartilage as well as 26/29 of the fascia group. This study confirms success of tympanoplasty among Nigerians, and recommends that subjective hearing assessment should form part of indicators for success following tympanoplasty.
Language and know-how
I address the assumption that communicative interaction is made possible by knowledge of a language. I argue that this assumption as it is usually expressed depends on an unjustified reification of language, and on an unsatisfactory understanding of ‘knowledge’. I propose instead that communicative interaction is made possible by (Rylean) know-how and by the development of (Davidsonian) passing theories. We then come to see that our focus ought to be, not on propositional knowledge of a language which we internally represent, but on the practical application of know-how in our understanding and interpretation of others.
The functional asymmetry of auditory cortex is reflected in the organization of local cortical circuits
The primary auditory cortex (A1) is organized tonotopically, with neurons sensitive to high and low frequencies arranged in a rostro-caudal gradient. We used laser scanning photostimulation in acute slices to study the organization of local excitatory connections onto layers 2 and 3 (L2/3) of the mouse A1. Consistent with the organization of other cortical regions, synaptic inputs along the isofrequency axis (orthogonal to the tonotopic axis) arose predominantly within a column. By contrast, we found that local connections along the tonotopic axis differed from those along the isofrequency axis: some input pathways to L3 (but not L2) arose predominantly out-of-column. In vivo cell-attached recordings revealed differences between the sound-responsiveness of neurons in L2 and L3. Our results are consistent with the hypothesis that auditory cortical microcircuitry is specialized to the one-dimensional representation of frequency in the auditory cortex.
from Nature Neuroscience
Cross-modal plasticity in specific auditory cortices underlies visual compensations in the deaf
When the brain is deprived of input from one sensory modality, it often compensates with supranormal performance in one or more of the intact sensory systems. In the absence of acoustic input, it has been proposed that cross-modal reorganization of deaf auditory cortex may provide the neural substrate mediating compensatory visual function. We tested this hypothesis using a battery of visual psychophysical tasks and found that congenitally deaf cats, compared with hearing cats, have superior localization in the peripheral field and lower visual movement detection thresholds. In the deaf cats, reversible deactivation of posterior auditory cortex selectively eliminated superior visual localization abilities, whereas deactivation of the dorsal auditory cortex eliminated superior visual motion detection. Our results indicate that enhanced visual performance in the deaf is caused by cross-modal reorganization of deaf auditory cortex and it is possible to localize individual visual functions in discrete portions of reorganized auditory cortex.
from Nature Neuroscience
Categorical speech representation in human superior temporal gyrus
Speech perception requires the rapid and effortless extraction of meaningful phonetic information from a highly variable acoustic signal. A powerful example of this phenomenon is categorical speech perception, in which a continuum of acoustically varying sounds is transformed into perceptually distinct phoneme categories. We found that the neural representation of speech sounds is categorically organized in the human posterior superior temporal gyrus. Using intracranial high-density cortical surface arrays, we found that listening to synthesized speech stimuli varying in small and acoustically equal steps evoked distinct and invariant cortical population response patterns that were organized by their sensitivities to critical acoustic features. Phonetic category boundaries were similar between neurometric and psychometric functions. Although speech-sound responses were distributed, spatially discrete cortical loci were found to underlie specific phonetic discrimination. Our results provide direct evidence for acoustic-to–higher order phonetic level encoding of speech sounds in human language receptive cortex.
from Nature Neuroscience
Assessing for generalized improvements in reading comprehension by intervening to improve reading fluency
The relationship between reading fluency and comprehension was evaluated in five 4th-grade students. These students were identified as being at risk of not meeting yearly goals in reading fluency and comprehension based on fall benchmark assessment data. A brief intervention assessment was used to determine which intervention components would be essential to improving reading fluency across the five participants. As a result, the combination of repeated practice with performance feedback and error correction was implemented using instructional-level reading materials twice per week for 30-minute sessions with progress monitored weekly using AIMSweb measures of oral reading fluency and comprehension. Empirical, single-case designs were used to evaluate the impact of the program across these five students with assessed, generalized improvements in comprehension. Results indicated increased rate of words read correctly per minute with generalized increases in comprehension for four of five participants. Implications for practice and directions for future research are discussed. © 2010 Wiley Periodicals, Inc.
Interactional quality depicted in infant and toddler videos: where are the interactions?
This study examined the social–emotional content and the quality of social interactions depicted in a sample of 58 DVDs marketed towards infants and toddlers. Infant-directed videos rarely used social interactions between caregiver and child or between peers to present content. Even when videos explicitly targeted social–emotional content, correlations between educational claims and the actual content of the videos were modest at best. Similarly, other domain content (e.g. language skills) that is best learned through high-quality social interactions was typically depicted without social interactions. The results suggest that producers of infant-directed media are not applying developmental principles or research evidence in ways that take full advantage of developmentally appropriate interaction strategies to present their content. Copyright © 2010 John Wiley & Sons, Ltd.
Introduction to the special issue: Reading comprehension: Assessment and intervention for understanding
No abstract is available for this article.
Perceptual invariance or orientation specificity in American Sign Language? Evidence from repetition priming for signs and gestures
Repetition priming has been successfully employed to examine stages of processing in a wide variety of cognitive domains including language, object recognition, and memory. This study uses a novel repetition priming paradigm in the context of a categorisation task to explore early stages in the processing of American Sign Language signs and self-grooming gestures. Specifically, we investigated the degree to which deaf signers’ and hearing nonsigners’ perception of these linguistic or nonlinguistic actions might be differentially robust to changes in perceptual viewpoint. We conjectured that to the extent that signers were accessing language-specific representations in their performance of the task, they might show more similar priming effects under different viewing conditions than hearing subjects. In essence, this would provide evidence for a visually based “lack of invariance” phenomenon. However, if the early stages of visual-action processing are similar for deaf and hearing subjects, then no such difference should be found.
New Gene Mutation Reveals New Cause Of Rare Neurological Diseases
Scientists have discovered a new cause of spastic ataxia, and believe this cause is also a trigger for other mitochondrial diseases neurological disorders that can lead to serious coordination, growth, visual, speech, and muscle defects.
Researchers Develop First Implanted Device To Treat Balance Disorder
A University of Washington Medical Center patient will be the world’s first recipient of a device that aims to quell the disabling vertigo associated with Meniere’s disease.
