Monthly Archives: June 2010
Kindergarten Predictors of Second Versus Eighth Grade Reading Comprehension Impairments
Multiple studies have shown that kindergarten measures of phonological awareness and alphabet knowledge are good predictors of reading achievement in the primary grades. However, less attention has been given to the early predictors of later reading achievement. This study used a modified best-subsets variable-selection technique to examine kindergarten predictors of early versus later reading comprehension impairments. Participants included 433 children involved in a longitudinal study of language and reading development. The kindergarten test battery assessed various language skills in addition to phonological awareness, alphabet knowledge, naming speed, and nonverbal cognitive ability. Reading comprehension was assessed in second and eighth grades. Results indicated that different combinations of variables were required to optimally predict second versus eighth grade reading impairments. Although some variables effectively predicted reading impairments in both grades, their relative contributions shifted over time. These results are discussed in light of the changing nature of reading comprehension over time. Further research will help to improve the early identification of later reading disabilities.
from the Journal of Learning Disabilities
Language Development, Literacy Skills, and Predictive Connections to Reading in Finnish Children With and Without Familial Risk for Dyslexia
Discriminative language markers and predictive links between early language and literacy skills were investigated retrospectively in the Jyväskylä Longitudinal Study of Dyslexia in which children at familial risk for dyslexia have been followed from birth. Three groups were formed on the basis of 198 children’s reading and spelling status. One group of children with reading disability (RD; n = 46) and two groups of typical readers from nondyslexic control (TRC; n = 84) and dyslexic families (TRD; n = 68) were examined from age 1.5 years to school age. The RD group was outperformed by typical readers on numerous language and literacy measures (expressive and receptive language, morphology, phonological sensitivity, RAN, and letter knowledge) from 2 years of age onward. The strongest predictive links emerged from receptive and expressive language to reading via measures of letter naming, rapid naming, morphology, and phonological awareness.
from the Journal of Learning Disabilities
Differential Effects of Neuromuscular Electrical Stimulation Parameters on Submental Motor-Evoked Potentials
Conclusions. Changes in corticobulbar excitability induced by NMES of the submental muscle group are frequency and dose dependent and only occur after NMES triggered by volitional swallowing. Underlying neural mechanisms are discussed.
Hearing Assessment—Reliability, Accuracy, and Efficiency of Automated Audiometry
Conclusions: Automated audiometry provides reliable, accurate, and time-efficient hearing assessments for normal-hearing and hearing-impaired adults. Combined with an asynchronous telehealth model it holds significant potential for reaching underserved areas where hearing health professionals are unavailable.
Hearing requires otoferlin-dependent efficient replenishment of synaptic vesicles in hair cells
Inner hair cell ribbon synapses indefatigably transmit acoustic information. The proteins mediating their fast vesicle replenishment (hundreds of vesicles per s) are unknown. We found that an aspartate to glycine substitution in the C2F domain of the synaptic vesicle protein otoferlin impaired hearing by reducing vesicle replenishment in the pachanga mouse model of human deafness DFNB9. In vitro estimates of vesicle docking, the readily releasable vesicle pool (RRP), Ca2+ signaling and vesicle fusion were normal. Moreover, we observed postsynaptic excitatory currents of variable size and spike generation. However, mutant active zones replenished vesicles at lower rates than wild-type ones and sound-evoked spiking in auditory neurons was sparse and only partially improved during longer interstimulus intervals. We conclude that replenishment does not match the release of vesicles at mutant active zones in vivo and a sufficient standing RRP therefore cannot be maintained. We propose that otoferlin is involved in replenishing synaptic vesicles.
from the Nature Neuroscience
Prolonged maturation of auditory perception and learning in gerbils
In humans, auditory perception reaches maturity over a broad age range, extending through adolescence. Despite this slow maturation, children are considered to be outstanding learners, suggesting that immature perceptual skills might actually be advantageous to improvement on an acoustic task as a result of training (perceptual learning). Previous non-human studies have not employed an identical task when comparing perceptual performance of young and mature subjects, making it difficult to assess learning. Here, we used an identical procedure on juvenile and adult gerbils to examine the perception of amplitude modulation (AM), a stimulus feature that is an important component of most natural sounds. On average, Adult animals could detect smaller fluctuations in amplitude (i.e., smaller modulation depths) than Juveniles, indicating immature perceptual skills in Juveniles. However, the population variance was much greater for Juveniles, a few animals displaying adult-like AM detection. To determine whether immature perceptual skills facilitated learning, we compared naïve performance on the AM detection task with the amount of improvement following additional training. The amount of improvement in Adults correlated with naïve performance: those with the poorest naïve performance improved the most. In contrast, the naïve performance of Juveniles did not predict the amount of learning. Those Juveniles with immature AM detection thresholds did not display greater learning than Adults. Furthermore, for several of the Juveniles with adult-like thresholds, AM detection deteriorated with repeated testing. Thus, immature perceptual skills in young animals were not associated with greater learning. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 70: 636-648, 2010
Treatment of a cochlear implant biofilm infection: a potential role for alternative antimicrobial agents
Treatment of infected cochlear implants with novel agents such as tea tree oil could significantly improve salvage outcome.
from the Journal of Laryngology and Otology
Qualitative aspects of learning, recall, and recognition in dementia
Objective: To determine whether learning and serial position effect (SPE) differs qualitatively and quantitatively among different types of dementia and between dementia patients and controls; we also wished to find out whether interference affects it. Materials and Methods: We administered the Malayalam version of the Rey Auditory Verbal Learning Test (RAVLT) to 30 cognitively unimpaired controls and 80 dementia patients [30 with Alzheimer's disease (AD), 30 with vascular dementia (VaD), and 20 with frontotemporal dementia (FTD)] with mild severity on the Clinical Dementia Rating Scale. Results: All groups were comparable on education and age, except the FTD group, who were younger. Qualitatively, the learning pattern and SPE (with primacy and recency being superior to intermediate) was retained in the AD, VaD, and control groups. On SPE in free recall, recency was superior to intermediate in the FTD group (P < 0.01 using Bonferroni correction). On recognition, the AD and VaD groups had more misses (P < 0.01), while the FTD group had more false positives (P < 0.01). Conclusion: Quantitative learning is affected by dementia. The pattern of qualitative learning remains unaltered in dementia in the early stages.
Researchers say ear tubes are safe for children with cochlear implants
Children who are being treated for hearing loss with cochlear implants can safely have ear tubes installed to help clear up infections, say researchers at the University of Alabama at Birmingham (UAB).
from News-Medical.net
In Tinnitus, Imaging Reveals How Brain Fails To Tune Out Phantom Sounds
About 40 million people in the U.S. today suffer from tinnitus, an irritating and sometimes debilitating auditory disorder in which a person “hears” sounds, such as ringing, that don’t actually exist. There isn’t a cure for what has long been a mysterious ailment, but new research suggests there may, someday, be a way to alleviate the sensation of this sound, says a neuroscientist from Georgetown University Medical Center (GUMC).
Annual Evidence Update on Health Needs of People with Learning Disabilities: 28 June – 2 July 2010
The latest evidence on this topic from NHS Evidence – learning disabilities
People with learning disabilities have a higher level of health needs than the general population, many of which are unmet. The Health Needs Annual Evidence Update 2010 will provide bibliographies of published research for the following key health issues:
Cancer
Challenging behaviour
Coronary heart disease
Epilepsy
Respiratory illness.
from NHS Evidence
In Stroke Rehab, Skip the ABC’s
People with damaged speech recover faster by focusing on harder words
Is the human left middle longitudinal fascicle essential for language? A brain electrostimulation study
Human brain pathways required for language processing are poorly known. A new white matter tract in humans, the middle longitudinal fascicle, has recently been anatomically determined by diffusion tensor imaging and suggested to be essential for language. Our aim is to determine the importance of the middle longitudinal fascicle for language processing. This study is based on 8 patients with glioma resection at least involving the superior temporal gyrus of the left dominant hemisphere. Language is systematically examined pre- and postoperatively at 3 months. Intraoperative electrostimulation is used to map cortical and subcortical structures as functional boundaries of the glioma resection, including those essential for language processing. The resections are extensive (on average 62 ml, ranging from 21 to 111 ml) and include a large part of the middle longitudinal fascicle in all patients. Intraoperatively, no interference with picture naming is observed by electrostimulation of the middle longitudinal fascicle, while in all patients the inferior fronto-occipital fascicle is identified by eliciting semantic paraphasia as functional boundary. Postoperatively, no new permanent language deficits are detected by systematic language examination. Therefore, we suggest that the middle longitudinal fascicle may participate but is not essential for language processing. Hum Brain Mapp, 2010. © 2010 Wiley-Liss, Inc.
from Human Brain Mapping
Brain Stimulation Seems to Boost Language Skills in Alzheimer’s Patients
THURSDAY, June 24 (HealthDay News) — People with Alzheimer’s who are losing their language skills may see some improvement by using a technique called repetitive transcranial magnetic stimulation (rTMS), early research by an Italian team suggests.
from HealthScout.com
New Metric Predicts Language Recovery Following Stroke
ScienceDaily (June 24, 2010) — A team of researchers led by NewYork-Presbyterian Hospital/Columbia University Medical Center has developed a method to predict post-stroke recovery of language by measuring the initial severity of impairment. Being able to predict recovery has important implications for stroke survivors and their families, as they plan for short and long-term treatment needs.
from ScienceDaily.com
