Statistical Analyses of Temporal Information in Auditory Brainstem Responses to Tones in Noise: Correlation Index and Spike-distance Metric

from JARO — Journal of the Association for Research in Otolaryngology

Abstract Gai and Carney (J Neurophysiol 96:2451–2464, 2006) previously explored the detection of tones in noise based on responses in the anteroventral cochlear nucleus; that study focused on temporal information in discharge reliability and analyses of neural responses related to the fine structure or envelope of the stimulus. Two additional temporal approaches, the correlation index (Joris et al., Hearing Res 216–217:19–30, 2006) and the spike-distance metric (Victor and Purpura, J Neurophysiol 76:1310–1326, 1996; Netw Comput Neural Syst 8:127–164, 1997), are tested in the present study. Trends in the correlation index as a function of stimulus level are similar to those of the synchronization coefficient (also called the vector strength) when the tone is presented alone. However, the present study found that trends in the correlation index did not agree with those of the synchronization coefficient for tones presented with relatively high-level background noise. Instead, trends in the correlation index generally agreed with those of the temporal reliability metric discussed in Gai and Carney (J Neurophysiol 96:2451–2464, 2006); that is, the correlation index decreased with increased tone level in the presence of relatively high-level background noise. The spike-distance metric, which was based on absolute spike times or on interspike intervals, was compared to the temporal measures described above, which were generally based on relative spike times. The results confirm that the spike-distance metric is not an optimal temporal metric. In addition, absolute spike times of primary-like responses generally contained much less temporal information than absolute spike times of chopper response types. The present study highlights the importance of relative spike-timing information as characterized by traditional and novel temporal measures.
Keywords detection – reliability – synchronization – mutual information – timing

The communication experiences of adult deaf people within their family during childhood in Cyprus

from Deafness and Education International

Abstract
This study investigates the personal communication memories and experiences of adult deaf people during their childhoods in their homes. In order to obtain relevant information in depth semi-structured interviews were conducted with twenty four Cypriot deaf individuals between the ages of 19 to 54 years with different family and school backgrounds. Those who graduated from the school for the deaf, and used sign language from an early age had negative communication experiences at home. It was found that they could not achieve communication either in CSL or orally with their hearing parents (n = 12). On the other hand, those participants who graduated from general schools did not record any negative memories, since they could communicate from an early age with their hearing parents through speech (n = 10). Similarly, the two participants, who attended the school for the deaf, and signed with their family Deaf members from an early age, described pleasant communication memories. This study suggests the importance of an early and mutual mode of communication between family members and the deaf children, regardless the communication modality to ensure pleasant family communication interchanges and experiences. This could be taken into consideration by people involved in deaf education, including service providers, educators, parents, and counselors. Copyright © 2008 John Wiley & Sons, Ltd.

The representation and processing of familiar faces in dyslexia: differences in age of acquisition effects

from Dyslexia

Abstract
Two under-explored areas of developmental dyslexia research, face naming and age of acquisition (AoA), were investigated. Eighteen dyslexic and 18 non-dyslexic university students named the faces of 50 well-known celebrities, matched for facial distinctiveness and familiarity. Twenty-five of the famous people were learned early in life, while the remaining 25 were first encountered more recently. There was no overall difference between the dyslexics and the non-dyslexics in the speed or the accuracy with which they named faces, suggesting that face naming is unimpaired in dyslexic adults. In keeping with previous findings, the results indicated a speed and accuracy advantage for early-acquired over late-acquired faces. In addition, a significant participant group × AoA interaction demonstrated that the non-dyslexic group was significantly faster to name early- than late-acquired faces, while the dyslexic group showed a much smaller and non-significant effect of AoA. The results suggest that there are differences in representation in dyslexia and that these may be linked to problems with attentional/executive function and automaticity. It is proposed that a more fine-grained approach to investigating dyslexia in adulthood should be adopted, in order to uncover cognitive as well as behavioural differences between dyslexics and non-dyslexics. Copyright © 2008 John Wiley & Sons, Ltd.

The tolerance of ambiguity in late cochlear-implanted pre-lingually deaf juveniles

from Clinical Otolaryngology

Objectives: To examine the ambiguity tolerance, i.e. the ability to perceive new, contradictory and complex situations as positive challenges, of pre-lingually deafened adolescents who received a cochlear implant after their eighth birthday and to identify those dimensions of ambiguity tolerance which correlate significantly with specific variables of their oral communication.

Design and setting: Clinical survey at an academic tertiary referral center.

Participants and main outcome measures: A questionnaire concerning communication and subjectively perceived changes compared to the pre-cochlear implant situation was completed by 13 pre-lingually deafened patients aged between 13 and 23 years, who received their cochlear implants between the ages of 8 and 17 years. The results were correlated with the ‘Inventory for Measuring Ambiguity Tolerance’.

Results: The patients showed a lower ambiguity tolerance with a total score of 134.5 than the normative group with a score of 143.1. There was a positive correlation between the total score for ambiguity tolerance and the frequency of ‘use of oral speech’, as well as between the subscale ‘ambiguity tolerance towards apparently insoluble problems’ and all five areas of oral communication that were investigated. Comparison of two variables of oral communication, which shows a significant difference pre- and postoperatively, yields a positive correlation with the subscale ‘ambiguity tolerance towards the parental image’.

Conclusions: Pre-lingually deafened juveniles with cochlear implant who increasingly use oral communication seem to regard the limits of a cochlear implant as an interesting challenge rather than an insoluble problem.

Failed voice restoration: closure of the tracheo-oesophageal fistula

from Clinical Otolaryngology

• Tracheo-oesophageal fistula and voice prosthesis have revolutionised voice rehabilitation, but are not without their complications.

• The most significant problem is widening of the tracheo-oesophageal fistula relative to the voice prosthesis and subsequent leaking.

• Three-layer surgical closure is a means of permanently closing a problematic fistula.

• Use of an interposition in situ muscle graft as a second layer provides an adequate, well vascularised barrier to prevent fistula reformation. Our technique provides a safe, effective method of closing a problematic tracheo-oesophageal fistula.

• We report a five case series in which 100% of patients acquired satisfactory closure of their fistulae and resolution of their symptoms.

Lexical and Grammatical Abilities in Deaf Italian Preschoolers: The Role of Duration of Formal Language Experience

from the Journal of Deaf Studies and Deaf Education

We evaluated language development in deaf Italian preschoolers with hearing parents, taking into account the duration of formal language experience (i.e., the time elapsed since wearing a hearing aid and beginning language education) and different methods of language education. Twenty deaf children were matched with 20 hearing children for age and with another 20 hearing children for duration of experience. Deaf children showed a significant delay in both vocabulary and grammar when compared to same-age hearing children yet a similar development compared to hearing children matched for duration of formal language experience. The delay in linguistic development could be attributable to shorter formal language experience and not to deafness itself. Deaf children exposed to spoken language accompanied by signs tended to understand and produce more words than children exposed only to spoken language. We suggest that deaf children be evaluated based on their linguistic experience and cognitive and communicative potential.

The Appropriateness of the NC State-Mandated Reading Competency Test for Deaf Students as a Criterion for High School Graduation

from the Journal of Deaf Studies and Deaf Education

Deaf students consistently score lower on standardized measures of reading comprehension than their hearing peers. Most of the studies that have been conducted to explain this phenomenon have focused on variables within the reader, and important differences have been found between deaf and hearing readers. More recently, in the face of increasingly high-stakes consequences, researchers are looking “outside” the reader, at the tests themselves, to determine whether there are fairness issues for special populations, such as deaf students. The study reported here, the first of its kind with deaf students, examines the North Carolina (NC) reading comprehension test. The study employs the same method used originally by NC to determine its appropriateness of the test for the general population of NC students. The experts in this article, like those in the original construction of the NC test, are familiar with the content of the reading curriculum in NC; however, the raters in this article bring a special perspective related to teaching and testing reading of students who are deaf. Findings from this study raise questions about the appropriateness of the NC reading test for deaf students. Implications for future research and instructional practice are discussed.

Effects of Endolymphatic Sac Drainage With Steroids for Intractable Meniere’s Disease: A Long-Term Follow-Up and Randomized Controlled Study

from Laryngoscope

Objective: Meniere’s disease is a common inner ear disease with an incidence of 15 to 50 per 100,000 population. Since Meniere’s disease is thought to be triggered by an immune insult to the inner ear, we examined intraendolymphatic sac application of steroids as a new therapeutic strategy for intractable Meniere’s disease.

Study Design: Prospective randomized controlled study.

Methods: Between 1996 and 2005, we enrolled and assigned 197 intractable Meniere’s patients to three groups in a randomized controlled trial: Group I (G-I)- patients who underwent endolymphatic sac drainage and steroid-instillation; Group II (G-II)-those who underwent endolymphatic sac drainage without steroid-instillation; and Group III (G-III)-those who declined endolymphatic sac drainage. Definitive spells and hearing in all three groups were determined for 2 to 7 years after treatment.

Results: According to the 1995 American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) criteria, 2-year results demonstrated that vertigo was completely controlled in 88.0% of patients in G-I (n = 100), 85.1% of patients in G-II (n = 47), and 8.0% in G-III (n = 50). Statistically, G-I = G-II>G-III. Hearing was improved in 49.0% of patients in G-I, 31.9% in G-II, and 6.0% in G-III (G-I>G-II>G-III). Results after 7 years showed that vertigo was completely controlled in 78.8% of patients in G-I, 79.2% in G-II, and 25.0% in G-III (G-I = G-II>G-III). Hearing improved in 36.5% of patients in G-I, 8.3% in G-II, and 0.0% in G-III (G-I>G-II = G-III).

Conclusions: From non-surgical observation in G-III for at least 7 years after treatment, steroids instilled into endolymphatic sac in G-I patients significantly improved hearing in intractable Meniere’s patients, more so than endolymphatic sac drainage without steroids in G-II patients.

Can Auditory and Visual Speech Perception Be Trained Within a Group Setting?

from the American Journal of Audiology

Purpose: This study attempted to determine whether auditory-only and auditory-visual speech perception could be trained in a group format.

Method: A randomized controlled trial with at least 16 participants per group was completed. A training-only group completed at least 5 hr of group speech perception training; a training plus psychosocial group completed at least 5 hr of group speech perception training and psychosocial exercises; and a control group did not receive training. Evaluations were conducted before and after training and included analytic and synthetic measures of speech perception, hearing loss–related and generic quality of life scales, and a class evaluation form.

Results: No significant group changes were measured on any of the analytic auditory-only or auditory-visual measures of speech perception, yet the majority of training participants (regardless of training group) reported improvement in auditory and auditory-visual speech perception. The training participants demonstrated a significant reduction on the emotional subscale of the hearing loss–related quality of life scale, while the control participants did not demonstrate a change on this subscale.

Conclusions: Benefits of group audiologic rehabilitation classes may not result from an actual improvement in auditory or visual speech perception abilities, but participants still perceive training in these areas as useful.

Establishing a Tinnitus Clinic in Your Practice

from the American Journal of Audiology

Purpose: While tinnitus is very common among the hearing impaired population, specific treatment for tinnitus is not provided in most clinics. This article provides a plan for establishing a tinnitus treatment program that can be implemented in stages at most audiology clinics.

Method: Preparation for establishing a tinnitus clinic includes having an overall plan regarding the type and degree of tinnitus management. Assessment involves a measurement of tinnitus and of the reaction a patient has to the tinnitus, including the use of handicap questionnaires. Management typically involves some form of counseling and sound therapy. Four problematic areas in tinnitus management are thoughts and emotions, hearing and communication, sleep, and concentration.

Conclusions: Licensed audiologists generally have the essential training necessary to provide counseling and sound therapy to treat tinnitus patients. We introduce 3 levels of treatment implementation, depending on whether the patient is curious, concerned, or distressed. Follow-up and referrals might be necessary in more severe cases. Finally, the development of a tinnitus clinic centers around establishing a need for individual treatment, creating a treatment plan, estimating the need for additional staff and resources, reimbursement options, and assessing the effectiveness of the program.

Measures of Follow-Up in Early Hearing Detection and Intervention Programs: A Need for Standardization

from the American Journal of Audiology

Purpose: To demonstrate the need for standardized data definitions and reporting for early hearing detection and intervention (EHDI) programs collecting information on newborn hearing screening and follow-up, and types of information best collected in a standardized manner.

Method: A hypothetical birth cohort was used to show the potential effects of nonstandardized definitions and data classifications on rates of hearing screening, audiologic follow-up, and hearing loss.

Results: The true screening rate in this cohort was 92.4%. The calculated rate was between 90.0% and 96.5%, depending on the measure used. Among children documented as screened and referred for follow-up, 61.0% received this testing. Only 49.0% were documented to have been tested. Despite a true prevalence of 3.7 per 1,000 births, only 1.5 per 1,000 children were documented with a hearing loss.

Conclusion: Ensuring that children receive recommended follow-up is challenging. Without complete reporting by audiologists to EHDI programs, accurate calculation of performance measures is impossible. Lack of documentation can lead to the overstatement of “loss to follow-up.” Also, standardization of measures is essential for programs to evaluate how many children receive recommended services and assess progress toward national goals. A new survey has been implemented to collect more detailed and standardized information about recommended services.

Parents’ Needs Following Identification of Childhood Hearing Loss

from the American Journal of Audiology

Purpose: Appropriate support for families of children diagnosed with hearing impairment may have a direct impact on the success of early hearing detection and intervention programs in reducing the negative effects of permanent hearing loss. We conducted a qualitative study to explore parents’ needs after learning of their child’s hearing loss to better understand the important components of service delivery from families’ perspectives.

Method: Semistructured interviews were conducted with 17 families (21 parents) of preschool children in 4 centers in Ontario, Canada. Parents of children identified by neonatal screening as well as those identified through traditional referral routes participated. We asked parents to share their perceptions of the strengths and gaps in the care system.

Results: Although the majority of parents were satisfied with the range and quality of audiology and therapy services available, they identified gaps in the areas of service coordination, availability of information, and the integration of social service and parent support into the system. Access to audiology services appears to have been facilitated for children who were systematically screened.

Conclusions: The findings provide insights into the services most valued by families. These findings highlight the importance of eliciting parents’ perspectives in designing optimal care models for children and families.

The Effect of Room Acoustics and Sound-Field Amplification on Word Recognition Performance in Young Adult Listeners in Suboptimal Listening Conditions

from the American Journal of Audiology

Purpose: To compare the speech recognition performance of young adult listeners with normal hearing in 2 college classrooms, only 1 of which met American National Standards Institute (ANSI) S12.60-2002 acoustic standards. Also, differences in speech recognition performance were compared in both classrooms with and without the use of a classroom amplification system. The speech was presented at low intensity to simulate listening in the rear seats of a large college classroom.

Method: Listeners were randomly assigned seats in the 2 classrooms, and Northwestern University Auditory Test No. 6 (NU-6) words were presented via a loudspeaker from the front of the classroom for all listening conditions as well as through a sound-field infrared system with ceiling-mounted speakers during the amplified condition.

Results: Results showed statistically significant differences in speech recognition performance between classrooms, with and without classroom amplification, and across the rows of each classroom when the classroom amplification system was not used.

Conclusions: These results demonstrate how meeting the ANSI S12.60-2002 standard, which was written for elementary school classrooms, can benefit young adult listeners in postsecondary classrooms. Also, classroom amplification was shown to improve speech recognition for students across the classroom in both acoustically poor and acoustically sound classroom environments.

Use of a Hearing and Balance Screening Survey With Local Primary Care Physicians

from the American Journal of Audiology

Purpose: This investigation is a follow-up to a national survey of hearing/balance screening and referrals in elderly patients by primary care physicians (PCPs). This local study focused on PCPs who actually treated elderly patients and could be contacted and followed in a single community.

Method: PCPs in Santa Barbara, CA, were surveyed with a 35-item questionnaire via mailings, phone calls, and hand delivery to determine their participation in, knowledge of, and attitudes toward hearing/balance screening and referrals for the elderly. Potential respondents were 154 PCPs obtained from WebMD, Google, and telephone and provider directories for Santa Barbara. Of the 154 surveys mailed/delivered, 33 were returned undeliverable or unusable, and 32 were returned usable, producing an overall response rate of 26.5%.

Results: Results were similar to those of the national study; PCPs were unlikely to screen for hearing/balance problems unless patients complained. The PCPs were unaware of patient self-report screening methods and probably would not use them in the future.

Conclusions: These PCPs acknowledged the importance of hearing/balance problems in the elderly, but their responses demonstrated insufficiencies in knowledge and potential attitudinal, time, and reimbursement obstacles that could interfere with their screening for hearing/balance problems. Audiologists should partner with PCPs to improve ways of meeting patients’ needs but must consider resource/payoff implications for such endeavours.

Word Recognition Materials for Native Speakers of Taiwan Mandarin

from the American Journal of Audiology

Purpose: To select, digitally record, evaluate, and psychometrically equate word recognition materials that can be used to measure the speech perception abilities of native speakers of Taiwan Mandarin in quiet.

Method: Frequently used bisyllabic words produced by male and female talkers of Taiwan Mandarin were digitally recorded and subsequently evaluated using 20 native listeners with normal hearing at 10 intensity levels (–5 to 40 dB HL) in increments of 5 dB.

Results: Using logistic regression, 200 words with the steepest psychometric slopes were divided into 4 lists and 8 half-lists that were relatively equivalent in psychometric function slope. To increase auditory homogeneity of the lists, the intensity of words in each list was digitally adjusted so that the threshold of each list was equal to the midpoint between the mean thresholds of the male and female half-lists.

Conclusions: Digital recordings of the word recognition lists and the associated clinical instructions are available on CD upon request.