Monthly Archives: January 2011

A Retrospective Chart Review of Dietary Diversity and Feeding Behavior of Children With Autism Spectrum Disorder Before and After Admission to a Day-Treatment Program

The nutritional status and mealtime performance among a group of children with autism spectrum disorders (ASD) were examined before and after admission to an intensive feeding day-treatment program. Treatment involved escape extinction, reinforcement, and stimulus fading procedures. Outcomes focused on dietary diversity and mealtime performance, including acceptance, swallowing, and disruptive mealtime behaviors. Upon admission, participants exhibited severely restricted diets, low rates of acceptance and swallowing, and high rates of disruptive mealtime behavior. Following treatment, significant improvements regarding food variety, consumption, and appropriate mealtime behavior were demonstrated. Gains were maintained after caregiver training was conducted and caregivers were introduced as the primary feeders.

from Focus on Autism and Other Developmental Disabilities

Advertisements

Communication Skills in Girls With Rett Syndrome

Rett Syndrome (RS) is an X-linked, neurodevelopmental disorder that occurs primarily in females and causes significant impairment in cognition, motor control, and communication. Teachers and speech-language pathologists (SLPs) encounter girls with RS with increasing frequency as awareness of the disorder increases, yet the literature on clinical interventions with this population is limited. Parents, teachers, and SLPs were surveyed regarding the communication abilities of these girls. Respondents reported that girls with RS use multiple modalities to communicate, with eye gaze the most frequently used modality, followed by picture/symbol systems and body movements. This study provides clinical information for professionals working with girls with RS, and supports the need for additional research on strategies to improve communication in RS.

from Focus on Autism and Other Developmental Disabilities

Repair Strategies Used by Verbal Students With Autism During Free Play

This study assessed the repair strategies used by verbal students with autism (N = 12) when faced with verbal requests for clarification, gestural requests, not attending and not responding, and wrong responses. Data were collected in request contexts contrived by the communication partner during free play. The results indicated that most of the students repaired more than 80% of the communication breakdowns. In addition, they tended to choose communication forms that reflected the social meaning of the breakdown. However, they were likely to rely on unconventional forms when they faced wrong response breakdowns.

from Focus on Autism and Other Developmental Disabilities

Own voice qualities (OVQ) in hearing-aid users: There is more than just occlusion

Objective. Hearing-aid users’ problems with their own voice caused by occlusion are well known. Conversely, it remains essentially undocumented whether hearing-aid users expected not to have occlusion-related problems experience own-voice issues. Design. To investigate this topic, a dedicated Own Voice Qualities (OVQ) questionnaire was developed and used in two experiments with stratified samples. Study sample. In the main experiment, the OVQ was administered to 169 hearing-aid users (most of whom were expected not to have occlusion-related problems) and to a control group of 56 normally-hearing people. In the follow-up experiment, the OVQ was used in a cross-over study where 43 hearing-aid users rated own voice for an open fitting and a small-vent earmould fitting. Results. The results from the main experiment show that hearing-aid users (without occlusion) have more problems than the normal-hearing controls on several dimensions of own voice. The magnitude of these differences was found to be generally larger than the differences observed between the open fitting and the small-vent fitting in the follow-up experiment. Conclusions. This suggests that own voice is a potentially important concern, even for hearing-aid users who are not expected to have occlusion-related problems.

from the <a href="http://informahealthcare.com/doi/abs/10.3109/14992027.2010.547991

Optimizing the perception of soft speech and speech in noise with the Advanced Bionics cochlear implant system

Objective: This study aimed to provide guidelines to optimize perception of soft speech and speech in noise for Advanced Bionics cochlear implant (CI) users. Design: Three programs differing in T-levels were created for ten subjects. Using the T-level setting that provided the lowest FM-tone, sound-field threshold levels for each subject, three additional programs were created with input dynamic range (IDR) settings of 50, 65 and 80 dB. Study sample: Subjects were postlinguistically deaf adults implanted with either the Clarion CII or 90K CI devices. Results: Sound-field threshold levels were lowest with T-levels set higher than 10% of M-levels and with the two widest IDRs. Group data revealed significantly higher scores for CNC words presented at a soft level with an IDR of 80 dB and 65 dB compared to 50 dB. Although no significant group differences were seen between the three IDRs for sentences in noise, significant individual differences were present. Conclusions: Setting Ts higher than the manufacturer’s recommendation of 10% of M-levels and providing IDR options can improve overall speech perception; however, for some users, higher Ts and wider IDRs may not be appropriate. Based on the results of the study, clinical programming recommendations are provided.

from the International Journal of Audiology

The difference between uni- and bilateral auditory phantom percept

Unilateral and bilateral tinnitus can be differentiated based on their resting state oscillation patterns: beta3 and gamma-band activity in the superior premotor cortex, parahippocampal area and angular gyrus seem to form the core of a spatial localization network involved in tinnitus.

from Clinical Neurophysiology

The ocular vestibular-evoked myogenic potential to air-conducted sound; probable superior vestibular nerve origin

Intense air-conducted sound (ACS) elicits an ocular vestibular-evoked myogenic potential (oVEMP), and it has been suggested that it does so by stimulating saccular receptors and afferents in the inferior vestibular nerve and so activating a crossed sacculo-ocular pathway. Bone conducted vibration (BCV) also elicits an oVEMP probably by activating utricular receptors and a crossed utriculo-ocular pathway. Are there two separate pathways mediating oVEMPs for ACS and BCV? If saccular receptors and afferents are primarily responsible for the oVEMP to ACS, then the oVEMP to ACS should be normal in patients with reduced or absent utricular function – unilateral superior vestibular neuritis (SVN). If utricular receptors and afferents are primarily responsible for oVEMP n10, then oVEMP to ACS should be reduced or absent in SVN patients, and in these patients there should be a close relationship between the size of the oVEMP n10 to BCV and to ACS.

from Clinical Neurophysiology

NIH Grant Enables Cochlear Implant Breakthrough

Many cochlear implant users may soon be able to easily modify the settings on their hearing devices using a smartphone interface, selecting one setting for a bustling restaurant, another for a hushed library.

from The University of Texas at Dallas News Center

Use of Glasgow Benefit Inventory (GBI) in Meniere’s disease managed with intratympanic dexamethasone perfusion: Quality of life assessment

The mean GBI score indicates substantial improvement in patients’ overall quality of life following intratympanic dexamethasone perfusion, which was also confirmed by the audiometric results.

from Auris Nasus Larynx

Associations between evaluation anxiety, cognitive interference and performance on working memory tasks

According to Cognitive Interference Theory, evaluation anxiety leads to increased negative off-task self-dialogue which then results in diminished cognitive performance. Given that negative off-task self-dialogue is primarily verbal, the phonological loop and central executive components of the working memory system should be most affected by evaluation anxiety. Eighty-eight participants were randomly assigned to receive evaluation anxiety inducing instructions or supportive instructions prior to administration of three tests (Digit Span, Visual Memory Span, and StroopColour-Word) that measured the phonological loop, visuospatial sketchpad, and central executive components of working memory. Measures of evaluation anxiety and negative off-task self-dialogue were obtained during and after testing. Results showed that participants receiving anxiety inducing instructions reported significantly more evaluation anxiety and off-task self-dialogue. They also had significantly lower performance on the Digit Span Test and the StroopColour-Word Test. Negative off-task self-dialogue also mediated the relationship between evaluation anxiety and performance on the Digit Span Test. Copyright © 2011 John Wiley & Sons, Ltd.

from Applied Cognitive Psychology

Complex primary afferents: What the distribution of electrophysiologically-relevant phenotypes within the spiral ganglion tells us about peripheral neural coding

Spiral ganglion neurons are the first neural element of the auditory system. They receive precise synaptic signals which represent features of sound stimuli encoded by hair cell receptors and they deliver a digital representation of this information to the central nervous system. It is well known that spiral ganglion neurons are selectively responsive to specific sound frequencies, and that numerous structural and physiological specializations in the inner ear increase the quality of this tuning, beyond what could be accomplished by the passive properties of the basilar membrane. Further, consistent with what we know about other sensory systems, it is becoming clear that the parallel divergent innervation pattern of type I spiral ganglion neurons has the potential to encode additional features of sound stimuli. To date, we understand the most about the sub-modalities of frequency and intensity coding in the peripheral auditory system. Work reviewed herein will address the issue of how intrinsic electrophysiological features of the neurons themselves have the potential to contribute to the precision of coding and transmitting information about these two parameters to higher auditory centers for further processing.

from Hearing Research

Development of tonotopy in the auditory periphery

Acoustic frequency analysis plays an essential role in sound perception, communication and behavior. The auditory systems of most vertebrates that perceive sounds in air are organized based on the separation of complex sounds into component frequencies. This process begins at the level of the auditory sensory epithelium where specific frequencies are distributed along the tonotopic axis of the mammalian cochlea or the avian/reptilian basilar papilla (BP). Mechanical and electrical mechanisms mediate this process, but the relative contribution of each mechanism differs between species. Developmentally, structural and physiological specializations related to the formation of a tonotopic axis form gradually over an extended period of time. While some aspects of tonotopy are evident at early stages of auditory development, mature frequency discrimination is typically not achieved until after the onset of hearing. Despite the importance of tonotopic organization, the factors that specify unique positional identities along the cochlea or basilar papilla are unknown. However, recent studies of developing systems, including the inner ear provide some clues regarding the signalling pathways that may be instructive for the formation of a tonotopic axis.

from Hearing Research

Recalibration of the auditory continuity illusion: Sensory and decisional effects

An interrupted sound can be perceived as continuous when noise masks the interruption, creating an illusion of continuity. Recent findings have shown that adaptor sounds preceding an ambiguous target sound can influence listeners’ rating of target continuity. However, it remains unclear whether these aftereffects on perceived continuity influence sensory processes, decisional processes (i.e., criterion shifts), or both. The present study addressed this question. Results show that the target sound was more likely to be rated as ‘continuous’ when preceded by adaptors that were perceived as clearly discontinuous than when it was preceded by adaptors that were heard (illusorily or veridically) as continuous. Detection-theory analyses indicated that these contrastive aftereffects reflect a combination of sensory and decisional processes. The contrastive sensory aftereffect persisted even when adaptors and targets were presented to opposite ears, suggesting a neural origin in structures that receive binaural inputs. Finally, physically identical but perceptually ambiguous adaptors that were rated as ‘continuous’ induced more reports of target continuity than adaptors that were rated as ‘discontinuous’. This assimilative aftereffect was purely decisional. These findings confirm that judgments of auditory continuity can be influenced by preceding events, and reveal that these aftereffects have both sensory and decisional components.

from Hearing Research

Orthographic context and the acquisition of orthographic knowledge in normal and dyslexic readers

We tested the hypothesis that the acquisition of orthographic knowledge of novel words that are presented in an indistinct context, that is a context with many orthographically similar words, would be more difficult for dyslexic than for normal readers. Participants were 19 Dutch dyslexic children (mean age 10;9 years), 20 age-matched and 20 reading-age-matched normal readers. During training the children repeatedly read a series of nonwords in a distinct (KWOG with KWES and SNAR) and an indistinct (KWOG with KWOS and KROG) orthographic context. At posttest, the dyslexic children were slower but more accurate in the reading of nonwords if these had been acquired in an indistinct than in a distinct training context. In normal readers context did not have an effect. We argue that dyslexic children’s sensitivity to orthographic context is due to their problems in the acquisition of fully specified orthographic representations causing interference by similar words. Copyright © 2011 John Wiley & Sons, Ltd.

from Dyslexia

Tracking Vocal Pitch through Noise: Neural Correlates in Nonprimary Auditory Cortex

In natural environments, a sound can be heard as stable despite the presence of other occasionally louder sounds. For example, when a portion in a voice is replaced by masking noise, the interrupted voice may still appear illusorily continuous. Previous research found that continuity illusions of simple interrupted sounds, such as tones, are accompanied by weaker activity in the primary auditory cortex (PAC) during the interruption than veridical discontinuity percepts of these sounds. Here, we studied whether continuity illusions of more natural and more complex sounds also emerge from this mechanism. We used psychophysics and functional magnetic resonance imaging in humans to measure simultaneously continuity ratings and blood oxygenation level-dependent activity to vowels that were partially replaced by masking noise. Consistent with previous results on tone continuity illusions, we found listeners’ reports of more salient vowel continuity illusions associated with weaker activity in auditory cortex (compared with reports of veridical discontinuity percepts of physically identical stimuli). In contrast to the reduced activity to tone continuity illusions in PAC, this reduction was localized in the right anterolateral Heschl’s gyrus, a region that corresponds more to the non-PAC. Our findings suggest that the ability to hear differently complex sounds as stable during other louder sounds may be attributable to a common suppressive mechanism that operates at different levels of sound representation in auditory cortex.

from the Journal of Neuroscience