Monthly Archives: November 2007
Hyperlink Format, Categorization Abilities and Memory Span as Contributors to Deaf Users Hypertext Access
Sixty deaf and hearing students were asked to search for goods in a Hypertext Supermarket with either graphical or textual links of high typicality, frequency, and familiarity. Additionally, they performed a picture and word categorization task and two working memory span tasks (spatial and verbal). Results showed that deaf students were faster in graphical than in verbal hypertext when the number of visited pages per search trial was blocked. Regardless of stimuli format, accuracy differences between groups did not appear, although deaf students were slower than hearing students in both Web search and categorization tasks (graphical or verbal). No relation between the two tasks was found. Correlation analyses showed that deaf students with higher spatial span were faster in graphical Web search, but no correlations emerged between verbal span and verbal Web search. A hypothesis of different strategies used by the two groups for searching information in hypertext is formulated. It is suggested that deaf users use a visual-matching strategy more than a semantic approach to make navigation decisions.
The Educational Interpreter Performance Assessment (EIPA) is as an important research tool for examining the quality of interpreters who use American Sign Language or a sign system in classroom settings, but it is not currently applicable to educational interpreters who use Cued Speech (CS). In order to determine the feasibility of extending the EIPA to include CS, a pilot EIPA test was developed and administered to 24 educational CS interpreters. Fifteen of the interpreters’ performances were evaluated two to three times in order to assess reliability. Results show that the instrument has good construct validity and test–retest reliability. Although more interrater reliability data are needed, intrarater reliability was quite high (0.9), suggesting that the pilot test can be rated as reliably as signing versions of the EIPA. Notably, only 48% of interpreters who formally participated in pilot testing performed at a level that could be considered minimally acceptable. In light of similar performance levels previously reported for interpreters who sign (e.g., Schick, Williams, & Kupermintz, 2006), these results suggest that interpreting services for deaf and hard-of hearing students, regardless of the communication option used, are often inadequate and could seriously hinder access to the classroom environment.
from the Journal of Voice
Contemporary commercial music (CCM) performers rely heavily on their voice, yet may not be aware of the importance of proactive voice care. This investigation intends to identify perceptions and barriers to seeking voice care among CCM artists. This cross-sectional observational study used a 10-item Likert-based response questionnaire to assess current perceptions regarding voice care in a population of randomly selected participants of professional CCM conference. Subjects (n=78) were queried regarding their likelihood to seek medical care for minor medical problems and specifically problems with their voice. Additional questions investigated anxiety about seeking voice care from a physician specialist, speech language pathologist, or voice coach; apprehension regarding findings of laryngeal examination, laryngeal imaging procedures; and the effect of medical insurance on the likelihood of seeking medical care. Eighty-two percent of subjects reported that their voice was a critical part of their profession; 41% stated that they were not likely to seek medical care for problems with their voice; and only 19% were reluctant to seek care for general medical problems (P<0.001). Anxiety about seeking a clinician regarding their voice was not a deterrent. Most importantly, 39% of subjects do not seek medical attention for their voice problems due to medical insurance coverage. The CCM artists are less likely to seek medical care for voice problems compared with general medical problems. Availability of medical insurance may be a factor. Availability of affordable voice care and education about the importance of voice care is needed in this population of vocal performers.
Laryngeal Manual Therapy: A Preliminary Study to Examine its Treatment Effects in the Management of Muscle Tension Dysphonia
from the Journal of Voice
The objectives of this study were to determine appropriate acoustic and outcome measures for the evaluation of a method of laryngeal manual therapy (LMT) used in the treatment of patients with muscle tension dysphonia (MTD). The effects of this technique were also investigated. The study was based on the hypotheses that the vertical position of the larynx in the vocal tract would lower, that the quality of the voice would normalize, and that a reduction in any vocal tract discomfort (VTD) would occur after LMT. This was a small, prospective, repeated measures pilot study in which each member of the research team was “blinded” to all other stages of the study and during which all data were anonymized until the final stage of data analysis. Ten subjects presenting with MTD completed outcome measures and provided audiorecordings immediately before, immediately after, and 1 week after LMT. The Kay CSL 4150 was used for signal acquisition and for some acoustic measurements. Spectrographic evaluation was accomplished with Praat. A new perceptual, self-rating scale, the VTD scale, and a new proforma for use by the clinician for palpatory evaluation, were developed for the study. Relative average perturbation during connected speech was significantly reduced after LMT, indicating a reduction in abnormal vocal function. The severity and frequency of VTD was shown to have reduced after LMT. This pilot study showed positive evidence for LMT as a method of therapy in the treatment of hyperfunctional voice disorders. Its effects were shown to be measurable with both acoustical analysis and the VTD scale.
A Retrospective Study Concerning the Psychosocial Impact of Voice Disorders: Voice Handicap Index Change in Patients With Benign Voice Disorders After Treatment (Measured With the Dutch Version of the VHI)
from the Journal of Voice
The goal of this study was to gain better understanding of psychosocial effects of benign voice problems as measured with the Dutch version of the Voice Handicap Index (VHI). The effect of voice problems on daily life differs from person to person. Over the last few decades there has been a growing understanding of the fact that the psychosocial effect of this medical problem needs to be acknowledged. The VHI is a known voice specific Quality-of-Life measuring instrument, which is often used for this purpose. In the University Medical Center Groningen, Groningen, the Netherlands, patients with voice problems are analyzed at a Voice Clinic by a multidisciplinary team of voice specialists. In this study, we have analyzed patients with benign voice problems before and after treatment in the period of April 2004 to October 2006. The study group consisted of 68 patients (39 female). For comparison reason, we included a control group (n=68), matched for age and gender. The mean VHI score of the patient group before treatment was 48.9 (SD=20.9). After treatment, there was a significant improvement to 28.3 (SD=20.5) (P<0.001). There was no significant difference between the VHI scores of men and women. As could be expected, voice disorders of different etiology showed different VHI scores. Before and after treatment, the patient group showed a statistically significantly higher VHI score (P<0.001) compared with the control group (mean VHI score of 3.62, SD=3.82). Patients with different voice problems seem to have different results with the VHI. Treatment leads to statistically significant improvement in VHI scores. The VHI has proven to be a good instrument to evaluate the psychosocial consequences of voice problems.
Background: Apraxia of speech (AOS) is generally considered a phonetic-motoric disorder. As such, it is reasonable to draw on the motor learning literature to develop interventions for improving articulation. The often cited problem of impaired voicing control is used to test the application of a variable practice approach to training skilled movements in AOS. It is predicted that variable practice – practising a behaviour over a range of possible values or contexts – increases accuracy and stability of a trained behaviour.
Aims: The aims of the study were to test the influence of variable practice conditions on acquisition and long-term maintenance of voiced and voiceless phonemes in words at the phrase/sentence level as well as on generalisation of treatment effects to phonemes of same and different manner. The protocol was tested on two individuals with moderate AOS, one of whom exhibited a concomitant moderate aphasia.
Methods & Procedures: A single subject multiple baseline across-subjects design was used to examine efficacy of treatment for improving control of voicing for three fricative/affricate phonemes (Participant 1) or three plosive phonemes (Participant 2). The training sets included two voiced phonemes and one voiceless phoneme, each presented in the initial position of 10 different words. This provided a range of voice onset times and a range of phonetic contexts for each target phoneme, thus providing the variable practice. The inclusion of a voiceless phoneme that was produced at a high level of accuracy during baseline was hypothesised to reduce the chance of overgeneralisation from voiced to voiceless phoneme production.
Outcomes & Results: Consistent with predictions, participants demonstrated improved production of trained voiced phonemes and generalisation of treatment effects to untrained phonemes of same manner only. These effects were maintained up to 3 months post-treatment. Results support training multiple fricatives or plosives in parallel in a variety of phonetic contexts (i.e., variable practice) as well as including a combination of voiced and voiceless phonemes in treatment to ensure maintenance of accurate voiceless phoneme production.
Conclusions: Results from two participants, varying in overall communication impairment severity, provide promising evidence that a variable practice approach to retraining speech behaviours in AOS is effective. Specifically, this approach resulted in long-term maintenance of treatment effects and generalisation of treatment effects to untrained phonemes within manner class. Just as importantly, it did not result in overgeneralisation of voicing to voiceless phonemes. Further testing is required before recommending general clinical application.
Background: Buccofacial apraxia (BFA) may be defined as the inability to perform voluntary movements of the larynx, pharynx, mandible, tongue, lips, and cheeks, while automatic or reflexive control of these structures is preserved. BFA frequently co-occurs with aphasia and apraxia of speech (AOS). The treatment and management of BFA has received little emphasis in the clinical literature. However, recent studies suggest that principles of motor learning may provide an improved means of treating a variety of apraxic disorders, including limb apraxia and AOS. Also, research in our laboratory has suggested that augmented (or extrinsic) feedback provided by an electromagnetic articulograph (EMA) system may lead to improved remediation of place-of-articulation errors in talkers with aphasia and AOS. Taken together, the data suggest that treatment based on motor training principles, including the use of augmented kinematic feedback, may be beneficial to individuals with BFA.
Aims: The aims of the present study were to explore whether BFA may be successfully treated with direct (restitutive) methods, and whether augmented kinematic feedback improves therapy effectiveness and maintenance.
Methods & Procedures: An ABA design with follow-up probes 6 weeks post-treatment was used to investigate two types of treatment for non-verbal oral errors produced by an individual with BFA. Over a 1-month period, the participant received structured motor practice for a set of oral gestures (“bite your upper lip”, “bite your lower lip”), and motor practice with EMA augmented feedback for a third oral gesture (“touch your upper lip and your lower lip, using your tongue”). Nine untrained oral motor behaviours were also probed throughout the experiment. The sessions were videotaped and later scored by two independent examiners who were unaware of the nature of the experiment.
Outcomes & Results: The main findings were (1) a mixed pattern of improvement with no lasting maintenance for the gestures treated with structured motor therapy, and (2) consistent improvement with maintenance at 6 weeks post-treatment for the gesture treated with augmented feedback therapy. In general, the observed gains were treatment specific, although possible cases of positive and negative stimulus were also observed.
Conclusions: Augmented feedback provided by an EMA system appears to provide improved treatment effectiveness and maintenance compared to structured motor practice. However, the current preliminary findings should be tested with additional controls and more subjects before any strong conclusions are drawn.
Exploring the factor structure of the La Trobe Communication Questionnaire: Insights into the nature of communication deficits following traumatic brain injury
Background: Self and close other reports of communication ability can provide a time-efficient means of evaluating conversational discourse after traumatic brain injury (TBI). The La Trobe Communication Questionnaire (LCQ) measures perceived communication ability from various sources including self-perceptions and perceptions of others. Content and test-retest reliability and discriminant validity of the LCQ have been demonstrated previously with adults following TBI.
Aims: This study was undertaken to explore the factor structure of the LCQ as revealed within the data collected from 88 adults with severe TBI and their close others.
Methods & Procedures: Construct validity was examined using a Principal Component Factor Analytic procedure with Varimax rotation.
Outcomes & Results: A seven-factor structure that accounted for 60.88% of the variance was revealed. Of the LCQ items, 27 clearly loaded on to one of the seven communication factors that were identified.
Conclusions: The factor structure that emerged depicts the multidimensional nature of conversation and the complex interplay between cognitive and communication processes that social discourse demands. These results support the construct validity of the LCQ and indicate that it can be used as a reliable and valid measure of communication ability after severe TBI.
Background: Previous research has shown that context improves aphasic individuals’ auditory comprehension. The specific contextual information that has been identified as beneficial includes semantic constraints, semantic plausibility, both predictive and non-predictive information, and familiar topics. However, context can also include familiar content such as the names of relatives, friends, local schools, and local stores.
Aims: The purpose of the present study was to assess the influence of familiar content on comprehension in individuals with aphasia. Specifically, it assessed whether individuals with aphasia answer questions about paragraphs more accurately when the paragraphs contain familiar content than when they do not.
Methods & Procedures: Eleven participants with aphasia and eleven participants without brain damage listened to short paragraphs that differed in the familiarity of the content included. In half of the paragraphs, the people and places were generic and not known specifically by the participants. In the other half, the people and places were known by the participants (as provided by a spouse or other close individual). Approximately half of the subsequent questions asked of the participants related to this targeted information and half related to other, more generic, information in the paragraphs.
Outcomes & Results: The questions relating to the paragraphs with the familiar content were answered more accurately than were the questions relating to the paragraphs with neutral content. For the participants with aphasia, this result occurred for the questions relating to both the targeted (and thus familiar) information and the non-targeted or neutral information. The extent to which each participant with aphasia benefited from the familiar content did not relate to age, education, time-post-onset, or comprehension and naming skills.
Conclusions: These results suggest that familiar content may be another type of context that enhances comprehension skills in individuals with aphasia. The results are interpreted with respect to attention and domain knowledge concepts.
Abstract Multiple investigations have determined that healthy adults swallow most often during exhalation and that exhalation regularly follows the swallow, even when a swallow occurs during inhalation. We hypothesized that persons with idiopathic Parkinson’s disease would demonstrate impaired breathing and swallowing coordination during spontaneous eating. Twenty-five healthy volunteers and 25 Parkinson’s disease patients spontaneously swallowed calibrated pudding and cookie portions while simultaneous nasal airflow and respiratory inductance plethysmography were used to track spontaneous breathing. Surface EMG was used to record the timing of each swallow within the respiratory cycle. When compared to the healthy control group, those with Parkinson’s disease swallowed significantly more often during inhalation and at low tidal volumes. The Parkinson’s participants also exhibited significantly more postswallow inhalation for both consistencies. Only the healthy subjects exhibited significantly longer deglutitive apnea when swallows that occurred during inhalation were compared with those that occurred during exhalation. The high incidence of oropharyngeal dysphagia and risk of aspiration pneumonia found in Parkinson’s disease patients may be partially attributable to impaired coordination of breathing and swallowing.
Abstract Children with CHARGE syndrome frequently experience long-term and complex feeding difficulties. This study investigated the prevalence and nature of feeding difficulties in a population of 39 children with CHARGE syndrome and explored the relationship between the clinical characteristics of the syndrome and feeding development. Information was collected via a survey (two questionnaires) completed by the parents. One questionnaire, the Pediatric Assessment Scale for Severe Feeding Problems, provided an objective measure of the current severity of feeding difficulties. Results of the survey indicated a high prevalence of long-term feeding issues in this population. Approximately 90% of the children had received tube feeding at some point in time. In contrast to previous literature, choanal atresia and heart malformations were not found to be significantly related to a higher severity of feeding difficulty or associated with long-term tube feeding. Cranial nerve dysfunction was found to be the primary clinical feature of CHARGE syndrome impacting feeding development, reflected in a high prevalence of weak sucking/chewing, swallowing difficulty, gastroesophageal reflux, and aspiration. The presence of these conditions in infancy suggests the likelihood of long-term feeding difficulty and warrants the ongoing attention of feeding specialists.
The brain’s perceptual stimuli are constantly changing: some of these changes are treated as invariances and are suppressed, whereas others are selectively amplified, giving emphasis to the distinctions that matter most. The starkest form of such amplification is categorical perception. In speech, for example, a continuum of phonetic stimuli gets carved into perceptually distinct categories. We used fMRI to measure the degree to which this process of selective amplification takes place. The most categorically processing area was the left supramarginal gyrus: stimuli from different phonetic categories, when presented together in a contrasting pair, were neurally amplified more than two-fold. Low-level auditory cortical areas, however, showed comparatively little amplification of changes that crossed category boundaries. Selective amplification serves to emphasize key stimulus differences, thereby shaping perceptual categories. The approach presented here provides a quantitative way to measure the degree to which such processing is taking place.
from Hearing Research
This manuscript reports the results of two studies on development of a test bank of sentences for use in study of learning of speech-in-noise (SIN) discrimination. Sentences were derived from the sentence lists of Bench et al., 1979 [Bench, J., Kowal, Å., Bamford, J., 1979. The BKB (Bamford–Kowal–Bench) sentence lists for partially-hearing children. Brit. J. Audiol. 13, 108–112]. In the first study these sentences were grouped into three different lists (each of 40 sentences) based on their previously-determined speech reception thresholds (SRTs), and used to study SIN discrimination. In each test with 40 sentences in the SIN task, within-session performance asymptoted rapidly, independent of masker type, sex of subjects, and type of sentence. Then, in a second study, six lists of sentences were created to study learning of SIN discrimination, in a new group of subjects. It was found that across-session learning was rapid regardless of noise type, and the same general pattern of learning occurred regardless of noise type; however the amount of learning differed, with a slightly greater amount of learning occurring in the condition with the more difficult noise masker.
from Noise & Health
This cross-sectional study was conducted among mill workers in a large market in Ibadan, southwest Nigeria. These workers are engaged in small scale businesses with little or no regulation of work exposures. Questionnaires administered to mill workers sought information on personal characteristics, length of time engaged in the job, type of milling done and symptoms of hearing impairment. Noise exposure and hearing impairment were assessed among 85 mill workers. Audiometry was done on mill workers and 45 controls with no known exposure to noise and no history of aural disease. Noise levels at work stations ranged from 88-90dB for small mills and 101-105 for larger mills. None of the workers used hearing protection. Analysis based on total number of ears showed that 56% of the workers had hearing impairment ranging from mild (49%) moderate (6.4%) to severe (0.6%) whilst 33% of the controls had hearing impairment which was mild (26%), moderate (7%) and no severe losses, P = 0.001. There was no association between age and hearing impairment but prevalence of hearing impairment was highest among those who had been engaged in the trade for more than 20 years. There is a need for regulation of small scale enterprises to protect the health of workers. Health education and provision of low cost ear plugs will reduce the occurrence and severity of hearing impairment among these low income workers.
Effects of irrelevant speech and traffic noise on speech perception and cognitive performance in elementary school children
from Noise & Health
The effects of background noise of moderate intensity on short-term storage and processing of verbal information were analyzed in 6 to 8 year old children. In line with adult studies on “irrelevant sound effect” (ISE), serial recall of visually presented digits was severely disrupted by background speech that the children did not understand. Train noises of equal Intensity however, had no effect. Similar results were demonstrated with tasks requiring storage and processing of heard information. Memory for nonwords, execution of oral instructions and categorizing speech sounds were significantly disrupted by irrelevant speech. The affected functions play a fundamental role in the acquisition of spoken and written language. Implications concerning current models of the ISE and the acoustic conditions in schools and kindergardens are discussed.