Monthly Archives: June 2011
I Want My MTV (a bit softer please)
You wouldn’t expect cable staple music channel, MTV, to be overly concerned about hearing loss. Head-banging-speed-metal has been around for a couple of decades and MTV has had plenty of these videos in its play list rotation over the years. But, in fact, MTV.com, in conjunction with the prestigious Vanderbilt Medical College, recently published a joint study that showed long-term exposure to loud music causes hearing loss.
from Healthy Hearing.com
The role of adolescents’ native language fluency on quality of communication and respect for parents in Chinese and Korean immigrant families.
This study examines whether loss of the native or parental language among adolescents from immigrant families has consequences for their relationships with their parents. The study sample included 614 ninth-grade adolescents from Chinese and Korean immigrant families. All adolescents completed measures of native and English language fluency, parental respect, and quality of communication. Results indicated a positive association between adolescents’ native fluency and parental respect, even after accounting for parents’ English fluency. In addition, quality of communication mediated the association between adolescent native fluency and parental respect. The findings support the contention that maintaining native language fluency may facilitate parent-adolescent communication due to its linguistic component as well as through greater understanding and respect for the culture heritage. (PsycINFO Database Record (c) 2011 APA, all rights reserved)
Exploring factors that affect the age of cochlear implantation in children
Conclusions
This study suggests that a substantial number of children will continue to receive cochlear implants well beyond their first birthday primarily due to progressive hearing loss. In addition, other medical conditions may contribute to delayed decisions in pediatric cochlear implantation.
from the International Journal of Pediatric Otorhinolaryngology
Understanding Perception Through Neural “Codes”
A major challenge for cognitive scientists is to deduce and explain the neural mechanisms of the rapid transposition between stimulus energy and recalled memory—between the specific (sensation) and the generic (perception)—in both material and mental aspects. Researchers are attempting three explanations in terms of neural codes. The microscopic code: cellular neurobiologists correlate stimulus properties with the rates and frequencies of trains of action potentials induced by stimuli and carried by topologically organized axons. The mesoscopic code: cognitive scientists formulate symbolic codes in trains of action potentials from feature-detector neurons of phonemes, lines, odorants, vibrations, faces, etc., that object-detector neurons bind into representations of stimuli. The macroscopic code: neurodynamicists extract neural correlates of stimuli and associated behaviors in spatial patterns of oscillatory fields of dendritic activity, which self-organize and evolve on trajectories through high-dimensional brain state space. This multivariate code is expressed in landscapes of chaotic attractors. Unlike other scientific codes, such as DNA and the periodic table, these neural codes have no alphabet or syntax. They are epistemological metaphors that experimentalists need to measure neural activity and engineers need to model brain functions. My aim is to describe the main properties of the macroscopic code and the grand challenge it poses: how do very large patterns of textured synchronized oscillations form in cortex so quickly?
Detection of early Alzheimer’s disease in MCI patients by the combination of MMSE and an episodic memory test.
Conclusions
Pr-AD might be distinguished from S-MCI at baseline using the combination of MMSE and CVLT-LDTR. These two neuropsychological predictors are relatively brief and may be readily completed in non-specialist clinical settings.
from BMC Neurology
Parkinson’s disease progression at 30 years: a study of subthalamic deep brain-stimulated patients
Clinical findings in Parkinson’s disease suggest that most patients progressively develop disabling non-levodopa-responsive symptoms during the course of the disease. Nevertheless, several heterogeneous factors, such as clinical phenotype, age at onset and genetic aspects may influence the long-term clinical picture. In order to investigate the main features of long-term Parkinson’s disease progression, we studied a cohort of 19 subjects treated with subthalamic nucleus deep brain stimulation after >20 years of disease, reporting clinical and neuropsychological data up to a mean of 30 years from disease onset. This group of patients was characterized by an early onset of disease, with a mean age of 38.63 years at Parkinson’s disease onset, which was significantly lower than in the other long-term subthalamic nucleus deep brain stimulation follow-up cohorts reported in the literature. All subjects were regularly evaluated by a complete Unified Parkinson’s Disease Rating Scale, a battery of neuropsychological tests and a clinical interview, intended to assess the rate of non-levodopa-responsive symptom progression. Clinical data were available for all patients at presurgical baseline and at 1, 3 and 5 years from the subthalamic nucleus deep brain stimulation surgical procedure, while follow-up data after >7 years were additionally reported in a subgroup of 14 patients. The clinical and neuropsychological performance progressively worsened during the course of follow-up; 64% of patients gradually developed falls, 86% dysphagia, 57% urinary incontinence and 43% dementia. A progressive worsening of motor symptoms was observed both in ‘medication-ON’ condition and in ‘stimulation-ON’ condition, with a parallel reduction in the synergistic effect of ‘medication-ON/stimulation-ON’ condition. Neuropsychological data also showed a gradual decline in the performances of all main cognitive domains, with an initial involvement of executive functions, followed by the impairment of language, reasoning and memory. Thirty years after the disease onset, most patients presented non-levodopa-responsive symptoms, although the effect of both subthalamic nucleus deep brain stimulation and dopaminergic therapies still showed significant efficacy on the main disease cardinal features. Nevertheless, compared with other subthalamic nucleus deep brain stimulation follow-up studies, which included patients with a shorter disease duration at the time of surgery, a higher prevalence of axial and non-levodopa-responsive symptoms was observed in the long-term evaluations, confirming that several complex aspects underlie the development of non-motor symptoms and other features of Parkinson’s disease progression, even in patients with an early disease onset and a prior long-lasting response to dopaminergic therapies.
from Brain
Atrophy, hypometabolism and white matter abnormalities in semantic dementia tell a coherent story
Semantic dementia, in which there is progressive deterioration of semantic knowledge, is associated with focal, typically asymmetric, temporal lobe degeneration. The ventrorostral temporal lobe is most severely affected and there is concordance between atrophy and reduced metabolic activity. In this study, we confirmed the veracity of this claim using 18F-fluorodeoxyglucose positron emission tomography and anatomical magnetic resonance images. The principal aim, however, was to understand the impact on neuronal projections from the ventrorostral temporal cortex lesion by studying the full extent of white matter changes, with no a priori assumptions about the nature or spatial location of the tracts involved. Using an unbiased voxel-wise approach known as tract-based spatial statistics, we compared results of whole-brain diffusion tensor imaging—absolute metrics of axial, radial and mean diffusion as well as fractional anisotropy—from 10 patients with mild/moderate semantic dementia and 21 matched controls. Distributions of increased absolute diffusivity and reduced fractional anisotropy for patients with semantic dementia were spatially concordant with each other. Abnormalities in all metrics were highly statistically significant in ventrorostral temporal white matter, more extreme on the left side, thus closely matching results from structural and functional imaging of grey matter. The most sensitive marker of change was radial diffusion. Local white matter tract abnormalities extended rostrally towards the frontal lobe and dorsocaudally towards the superior temporal and supramarginal gyri. To examine more remote changes, we performed a skeletonized probabilistic tractography analysis—‘seeding’ the rostral temporal voxels identified as abnormal in the patient group—in a healthy control group. Three major neural pathways were found to emanate from this ‘seed region’: uncinate, arcuate and inferior longitudinal fasciculi. At a less conservative threshold, tensor abnormalities in the semantic dementia group mapped onto the tractographies for the uncinate and arcuate bundles well beyond the rostral temporal lobe; this was not the case for the inferior longitudinal bundle, where abnormalities in semantic dementia did not extend caudal to the atrophic/hypometabolic zone. The results offer direct evidence for how the ventrorostral temporal lesion, proposed to be responsible for deteriorating semantic knowledge in semantic dementia and separate from ‘classic’ language areas, is associated with degeneration of efferent white matter projections to such language areas.
from Brain
2011 National Conference on Childhood Apraxia of Speech
Sponsored by The Childhood Apraxia of Speech Association of North America (CASANA), the conference will take place in San Diego, CA July 7-9, 2011. The conference is for parents and caregivers, speech-language pathologists, and other professionals. ASHA CEU’s will be offered. More information.
A New Spin on the Vestibular Test Battery: Dynamic Visual Acuity and Subjective Visual Vertical
Although DVA and SVV have been part of the vestibular repertoire for some time, they have not routinely been part of the standard VNG assessment given the additional equipment required. Until now, that is.
from the ASHA Leader
Clinical management of stuttering in children and adults
Evidence from randomised trials has shown that treatment before 6 years of age reduces the chance of stuttering becoming intractable.
from BMJ
Otoacoustic Emissions, Mis-Match Negativity, and Hearing Screenings: Interview with Rebekah F. Cunningham, PhD
Douglas L. Beck, AuD, speaks with Dr. Cunnhingham about OAEs, transient OAEs, distortion product OAEs, auditory neuropathy spectrum disorders, and more.
from the American Academy of Audiology
Voice Foundation’s 40th Annual Meeting Introduces A Multidimensional Remote Consultative Strategy for Performers Presented by Cleveland Clinic and Yamaha Music & Wellness Physicians
Physicians introduce cutting-edge remote diagnostic strategies for both musicians and vocal performers.
from PRWeb.com
The relationship between binaural benefit and difference in unilateral speech recognition performance for bilateral cochlear implant users
Conclusions: The results indicate that subjects who show symmetry in speech recognition performance between implanted ears in general show a large binaural benefit.
from the International Journal of Audiology
Voice gender discrimination provides a measure of more than pitch-related perception in cochlear implant users
Conclusions: VGD measured with selected stimulus sets might be useful for assessing not only pitch-related perception, but also spectral and temporal processing by individual CI users. In addition to improvements in spectral resolution and modulation detection, the improvement in higher modulation frequency discrimination might be particularly important for CI users in noisy environments.
from the International Journal of Audiology
