Monthly Archives: February 2011
The right to assistive technology: for whom, for what, and by whom?
Despite its facilitating role in creating opportunities for people with disabilities to exercise human rights, access to assistive technology is limited in many countries. It is therefore promising that the Convention on Rights of Persons with Disabilities (CRPD) addresses this area. The purpose of this study was to analyse the assistive technology content of the CRPD from a basic human rights perspective in order to clarify its limitations and opportunities for formulation of policies and implementation strategies. Data were collected through a content analysis of the CRPD. It is concluded that a non-discriminatory interpretation of the provisions entitles all people with disabilities to a right to demand available and affordable assistive technology. Ensuring this right is a national as well as an international responsibility.
from Disability & Society
Affective priming with auditory speech stimuli
Four experiments explored the applicability of auditory stimulus presentation in affective priming tasks. In Experiment 1, it was found that standard affective priming effects occur when prime and target words are presented simultaneously via headphones similar to a dichotic listening procedure. In Experiment 2, stimulus onset asynchrony (SOA) was varied in the same procedure. Significant priming effects occurred only when prime and target stimuli were presented simultaneously or partly overlapping (SOA=250 ms), but not if they were presented clearly separable (SOA=500 ms). In Experiment 3, an auditory masking procedure was implemented with binaural prime and target presentation to demonstrate that auditory priming effects also occur under conditions of limited prime awareness. In Experiment 4, an unmasked auditory priming procedure with binaural prime and target presentations generated comparable affective priming effects in a social attitude domain (i.e., intergroup attitudes). Results of all four experiments show that affective priming effects can be found with auditory presented stimuli, thus enlarging the tool box of affective priming research.
The clinical and molecular genetic features of idiopathic infantile periodic alternating nystagmus
Periodic alternating nystagmus consists of involuntary oscillations of the eyes with cyclical changes of nystagmus direction. It can occur during infancy (e.g. idiopathic infantile periodic alternating nystagmus) or later in life. Acquired forms are often associated with cerebellar dysfunction arising due to instability of the optokinetic-vestibular systems. Idiopathic infantile periodic alternating nystagmus can be familial or occur in isolation; however, very little is known about the clinical characteristics, genetic aetiology and neural substrates involved. Five loci (NYS1-5) have been identified for idiopathic infantile nystagmus; three are autosomal (NYS2, NYS3 and NYS4) and two are X-chromosomal (NYS1 and NYS5). We previously identified the FRMD7 gene on chromosome Xq26 (NYS1 locus); mutations of FRMD7 are causative of idiopathic infantile nystagmus influencing neuronal outgrowth and development. It is unclear whether the periodic alternating nystagmus phenotype is linked to NYS1, NYS5 (Xp11.4-p11.3) or a separate locus. From a cohort of 31 X-linked families and 14 singletons (70 patients) with idiopathic infantile nystagmus we identified 10 families and one singleton (21 patients) with periodic alternating nystagmus of which we describe clinical phenotype, genetic aetiology and neural substrates involved. Periodic alternating nystagmus was not detected clinically but only on eye movement recordings. The cycle duration varied from 90 to 280 s. Optokinetic reflex was not detectable horizontally. Mutations of the FRMD7 gene were found in all 10 families and the singleton (including three novel mutations). Periodic alternating nystagmus was predominantly associated with missense mutations within the FERM domain. There was significant sibship clustering of the phenotype although in some families not all affected members had periodic alternating nystagmus. In situ hybridization studies during mid-late human embryonic stages in normal tissue showed restricted FRMD7 expression in neuronal tissue with strong hybridization signals within the afferent arms of the vestibulo-ocular reflex consisting of the otic vesicle, cranial nerve VIII and vestibular ganglia. Similarly within the afferent arm of the optokinetic reflex we showed expression in the developing neural retina and ventricular zone of the optic stalk. Strong FRMD7 expression was seen in rhombomeres 1 to 4, which give rise to the cerebellum and the common integrator site for both these reflexes (vestibular nuclei). Based on the expression and phenotypic data, we hypothesize that periodic alternating nystagmus arises from instability of the optokinetic-vestibular systems. This study shows for the first time that mutations in FRMD7 can cause idiopathic infantile periodic alternating nystagmus and may affect neuronal circuits that have been implicated in acquired forms.
from Brain
Assessment of theory of mind in children with communication disorders: Role of presentation mode
Children with communication disorders have problems with both language and social interaction. The theory-of-mind hypothesis provides an explanation for these problems, and different tests have been developed to test this hypothesis. However, different modes of presentation are used in these tasks, which make the results difficult to compare. In the present study, the performances of typically developing children, children with specific language impairments, and children with autism spectrum disorders were therefore compared using three theory-of-mind tests (the Charlie test, the Smarties test, and the Sally-and-Anne test) presented in three different manners each (spoken, video, and line drawing modes). The results showed differential outcomes for the three types of tests and a significant interaction between group of children and mode of presentation. For the typically developing children, no differential effects of presentation mode were detected. For the children with SLI, the highest test scores were consistently evidenced in the line-drawing mode. For the children with ASD, test performance depended on the mode of presentation. Just how the children’s non-verbal age, verbal age, and short-term memory related to their test scores was also explored for each group of children. The test scores of the SLI group correlated significantly with their short-term memory, those of the ASD group with their verbal age. These findings demonstrate that performance on theory-of-mind tests clearly depend upon mode of test presentation as well as the children’s cognitive and linguistic abilities.
MIRE-IL methodology applied to measuring the noise attenuation of earmuff hearing protectors
This article describes an objective methodology for measuring the noise attenuation of earmuff hearing protectors using as a reference the method known as microphone-in-real-ear (MIRE). The methodology implements the insertion loss (IL) paradigm, in which IL is measured using miniature microphones, specially designed to comply with ANSI and ISO standards for the MIRE technique. The results for four different hearing protectors are compared with the subjective method known as real-ear-attenuation-at-threshold (REAT). Correction factors are included in the methodology to account for external effects such as physiological noise and bone conduction. The objective method predicted well the real protection of the earmuffs and the proposed methodology showed lower standard deviation values than the REAT method.
from Applied Acoustics
Simple Composition: A Magnetoencephalography Investigation into the Comprehension of Minimal Linguistic Phrases
The expressive power of language lies in its ability to construct an infinite array of ideas out of a finite set of pieces. Surprisingly, few neurolinguistic investigations probe the basic processes that constitute the foundation of this ability, choosing instead to focus on relatively complex combinatorial operations. Contrastingly, in the present work, we investigate the neural circuits underlying simple linguistic composition, such as required by the minimal phrase “red boat.” Using magnetoencephalography, we examined activity in humans generated at the visual presentation of target nouns, such as “boat,” and varied the combinatorial operations induced by its surrounding context. Nouns in minimal compositional contexts (“red boat”) were compared with those appearing in matched non-compositional contexts, such as after an unpronounceable consonant string (“xkq boat”) or within a list (“cup, boat”). Source analysis did not implicate traditional language areas (inferior frontal gyrus, posterior temporal regions) in such basic composition. Instead, we found increased combinatorial-related activity in the left anterior temporal lobe (LATL) and ventromedial prefrontal cortex (vmPFC). These regions have been linked previously to syntactic (LATL) and semantic (vmPFC) combinatorial processing in more complex linguistic contexts. Thus, we suggest that these regions play a role in basic syntactic and semantic composition, respectively. Importantly, the temporal ordering of the effects, in which LATL activity (∼225 ms) precedes vmPFC activity (∼400 ms), is consistent with many processing models that posit syntactic composition before semantic composition during the construction of linguistic representations.
from the Journal of Neuroscience
Topographic Mapping of a Hierarchy of Temporal Receptive Windows Using a Narrated Story
Real-life activities, such as watching a movie or engaging in conversation, unfold over many minutes. In the course of such activities, the brain has to integrate information over multiple time scales. We recently proposed that the brain uses similar strategies for integrating information across space and over time. Drawing a parallel with spatial receptive fields, we defined the temporal receptive window (TRW) of a cortical microcircuit as the length of time before a response during which sensory information may affect that response. Our previous findings in the visual system are consistent with the hypothesis that TRWs become larger when moving from low-level sensory to high-level perceptual and cognitive areas. In this study, we mapped TRWs in auditory and language areas by measuring fMRI activity in subjects listening to a real-life story scrambled at the time scales of words, sentences, and paragraphs. Our results revealed a hierarchical topography of TRWs. In early auditory cortices (A1+), brain responses were driven mainly by the momentary incoming input and were similarly reliable across all scrambling conditions. In areas with an intermediate TRW, coherent information at the sentence time scale or longer was necessary to evoke reliable responses. At the apex of the TRW hierarchy, we found parietal and frontal areas that responded reliably only when intact paragraphs were heard in a meaningful sequence. These results suggest that the time scale of processing is a functional property that may provide a general organizing principle for the human cerebral cortex.
from the Journal of Neuroscience
A Melodic Contour Repeatedly Experienced by Human Near-Term Fetuses Elicits a Profound Cardiac Reaction One Month after Birth
Thus, 3-weeks of prenatal exposure to a specific melodic contour affects infants ‘auditory processing’ or perception, i.e., impacts the autonomic nervous system at least six weeks later, when infants are 1-month old. Our results extend the retention interval over which a prenatally acquired memory of a specific sound stream can be observed from 3–4 days to six weeks. The long-term memory for the descending melody is interpreted in terms of enduring neurophysiological tuning and its significance for the developmental psychobiology of attention and perception, including early speech perception, is discussed.
from PLoS ONE
Lack of Infection with XMRV or Other MLV-Related Viruses in Blood, Post-Mortem Brains and Paternal Gametes of Autistic Individuals
No MLV-related virus was detected in blood, brain, and semen samples of ASD patients or fathers. Hence infection with XMRV or other MLV-related viruses is unlikely to contribute to autism pathogenesis.
from PLoS ONE
Metaphors We Think With: The Role of Metaphor in Reasoning
The way we talk about complex and abstract ideas is suffused with metaphor. In five experiments, we explore how these metaphors influence the way that we reason about complex issues and forage for further information about them. We find that even the subtlest instantiation of a metaphor (via a single word) can have a powerful influence over how people attempt to solve social problems like crime and how they gather information to make “well-informed” decisions. Interestingly, we find that the influence of the metaphorical framing effect is covert: people do not recognize metaphors as influential in their decisions; instead they point to more “substantive” (often numerical) information as the motivation for their problem-solving decision. Metaphors in language appear to instantiate frame-consistent knowledge structures and invite structurally consistent inferences. Far from being mere rhetorical flourishes, metaphors have profound influences on how we conceptualize and act with respect to important societal issues. We find that exposure to even a single metaphor can induce substantial differences in opinion about how to solve social problems: differences that are larger, for example, than pre-existing differences in opinion between Democrats and Republicans.
from PLoS ONE
Comparison of glass ionomer cement and incus interposition in reconstruction of incus long process defects
The ossicles may be affected through the mass effect of the pathological tissue in chronic otitis media. Ossicular reconstruction may be accomplished using the patients’ own ossicles or with alloplastic materials. Glass ionomer ossiculoplasty is a fast, efficient, safe and cost-effective method and it has been used more frequently in recent years. Forty-six patients who had surgery for chronic otitis media were included in this study. All patients had an incus long process defect and a normal stapes superstructure. Ossicular reconstruction was performed using glass ionomer cement (GIC) (Ketac-Cem, Espe Dental AG, Seefeld, Germany) in 23 patients (group 1), while incus interposition was performed in other 23 patients (group 2). Preoperative and postoperative air pure tone averages of the group 1 patients were 42.8 and 35.2 dB, respectively (p < 0.01). These values were 42.9 and 34.5 dB in group 2 (p 0.05). The air bone gap of group 1 was 27 dB preoperatively and 20.7 dB postoperatively. These values were 28.7 and 20.2 dB, respectively, in group 2. The closure of air bone gap was statistically significant in both the groups (p < 0.01, p 0.05). In conclusion, the use of both GIC ossiculoplasty and incus interposition are efficient methods for reconstruction of incus long process and one is not superior to the other. A larger study population may be useful for comparison of these methods.
Randomised, multi-centre study of the usefulness of the heat and moisture exchanger (Provox HME®) in laryngectomised patients
This study included 60 patients (30 in Nice and 30 in Reims), who were randomised between a control group that used no device of this type and a group equipped with the Provox HME®. After 3 months of using the device, a notable improvement was found which was statistically significant with regard to cough (P = 0.00174) and to bronchorrhoea (P = 0.0031), and very close to achieving significance with regard to breathing effort. An overall improvement in the prosthetic (tracheo-oesophageal) voice was found in the 21 patients using the HME® and a voice prosthesis for all of the parameters studied. The device was used daily by 80% of the patients of whom 42% used it day and night at the end of the 3 months. Seven patients suffered from minor cutaneous intolerance (of whom 6 had received radiation therapy), which did not require the use of the HME® to be abandoned (PC). After 3 months, patients were asked the following questions: “Do you feel any improvement?”: 92% of affirmative answers; “Are you breathing better?”: 88% of affirmative answers; “Are you speaking more easily?”: 81% had experienced speech improvement. The general adaptation to the device was judged to be satisfactory for 95% of the patients after 3 months. The results of this randomised study show an improvement in the pulmonary symptoms and in the prosthetic voice after 3 months of using Provox HME®. This light and easy-to-use device appears to us to afford a significantly improved quality of life for laryngectomees and should be offered systematically during functional rehabilitation of these patients.
New Method of Hearing Testing Introduced by PHSI and Audigence
Physician Hearing Services, Inc. (PHSI), a Florida-based provider of hearing programs and services for ophthalmology specialists, is excited to share the news about the ground-breaking method of testing for hearing loss developed by Audigence. Clarujust™, an Audigence creation, utilizes new technology which reduces errors and ensures diagnostic accuracy based on mathematical algorithms performed by a computer when profiling digital hearing aids and cochlear implants.
from PRWeb.com
Talking on a Cell Phone Changes Brain Activity
Holding a cell phone against your ear changes the activity in your brain, according to a new study that shows the brain is sensitive to the phone’s radiation emissions.
from Sci-Tech Today
