Properties of binaural vestibular evoked myogenic potentials elicited with air-conducted and bone-conducted tone bursts.

The purpose of this investigation was to compare the effects of monaural and binaural stimulation on unilaterally-measured vestibular evoked myogenic potential (VEMP) magnitude and latency. The subjects were eighteen normal-hearing adults with no history of vestibular disease. Monaural VEMPs were acquired with air-conducted (AC) and bone-conducted (BC) 500 Hz tone bursts presented at 95 dB nHL and 70 dB nHL, respectively.

A role for the inferior colliculus in multisensory speech integration.

Multisensory integration can occur at relatively low levels within the central nervous system. Recent evidence suggests that multisensory audio-visual integration for speech may have a subcortical component, as acoustic processing in the human brainstem is influenced by lipreading during speech perception. Here, stimuli depicting the McGurk illusion (a demonstration of auditory-visual integration using speech stimuli) were presented to a 12-year-old child (FX) with a circumscribed unilateral lesion of the right inferior colliculus.

Long-term stability of N1 sources using low-resolution electromagnetic tomography.

The purpose of this study was to investigate the long-term stability of auditory N1 sources using low-resolution electromagnetic tomography (LORETA). Data collected from 72 electrodes in ten young adult female participants were analyzed. For each participant, N1 peak amplitude and latency values at Cz (referred to M2) were compared for right, left, and bilateral stimulation across three separate recording sessions.

School-aged children's phonological production of derived English words.

Purpose: Little is known about the phonological aspects of derivational processes. Neutral suffixes (e.g.

Effects of neuromuscular electrical stimulation on submental muscle activity.

Neuromuscular electrical stimulation (NMES) therapy has been proposed as a treatment option for pharyngeal dysphagia. However, little is known about the effects, if any, that NMES has on specific biomechanical aspects of the pharyngeal swallow. The purpose of this study was to determine if two weeks of NMES applied to the submental muscles increased myoelectric activity.

Videofluoroscopic and laryngoscopic evaluation of the upper airway and larynx of professional bassoon players.

The bassoon is a demanding double-reed woodwind instrument requiring exquisite control of airflow and air pressure to the reed to produce desired tonal characteristics. Little information is available from direct visualization of the vocal tract and larynx of the bassoonist while playing. Of particular interest is the mechanism(s) of vibrato.

Supplementary formulas and tables for calculating and interconverting speech recognition scores in transformed arcsine units.

Formulas that convert speech recognition scores, in percent or proportions, into units based on the arcsine transform have been described previously. This report reviews that work and presents various supplementary equations and tables for calculating and interconverting the proposed units. The relative merits of these data and their application to scores from closed-set tests are also discussed.

Speech perception benefits from sound field FM amplification.

The effects of sound field FM amplification (SFA) on speech perception performance were investigated in this 2-year study. Kindergarten children with normal hearing were randomly assigned to a treatment group, which comprised 7 classrooms that had SFA systems installed in them, and to a control group, which comprised another 7 classrooms that did not have any amplification available. The children were followed from the beginning of kindergarten through the end of first grade.

Use of speech production repair strategies to improve diver communication.

The purpose of this investigation was to determine if speech intelligibility improved when divers made specific modifications to their speaking patterns while in a hyperbaric helium-oxygen (heliox) environment. Divers were trained to produce a variety of sentences using speech with three types of alterations: (1) slowed rate, (2) increased loudness, and (3) a combination of slightly slowed rate, a minimal increase in loudness, increased pause time, and greater mouth opening (composite strategy). Both diver and non-diver listeners judged these sentences for intelligibility.

Quantitative and graphic acoustic analysis of phonatory modulations: the modulogram.

A method is presented for analyzing phonatory instabilities that occur as modulations of fundamental frequency (f0) and sound pressure level (SPL) on the order of 0.2 to 20 cycles per second. Such long-term phonatory instabilities, including but not limited to traditional notions of tremor, are distinct from cycle-to-cycle perturbation such as jitter or shimmer.

Effects of cuff deflation and one-way tracheostomy speaking valve placement on swallow physiology.

This study examined the effects of tracheostomy cuff deflation and one-way speaking valve placement on swallow physiology. Fourteen nonventilator-dependent patients completed videofluoroscopic swallow studies (VFSS) under three conditions: (1) cuff inflated, (2) cuff deflated, and (3) one-way valve in place. Four additional patients with cuffless tracheostomy tubes completed VFSS with and without the one-way valve in place.

Incidence of non-rhotic vowel errors in children: data from the Memphis Vowel Project.

Attention to vowels in phonological development and disorders has increased in recent years, but the incidence of vowel errors in children with phonological disorders has not yet been determined. In the present study, percentage of non-rhotic vowels correct (PVC-NR) was measured in single word productions of 314 monolingual American English-speaking children, 165 with normal phonology (NP) and 149 with delayed/disordered phonology (DP). Three cutoffs (PVC-NR < 85, < 90 and < 95) were used to determine incidence of vowel errors.

English derivational suffix frequency and children's stress judgments.

Considering the importance of word and stem frequency in the adult lexical processing literature, and the effect of input frequency on children's acquisition of words (Tardif, Shatz, and Naigles, 1997), it was hypothesized that children's acquisition of English morphologically conditioned stress alternations would be affected by the frequency with which children were exposed to different stress-changing suffixes (e.g., -tion, -ity, and -ic).

American and Swedish children's acquisition of vowel duration: effects of vowel identity and final stop voicing.

Vowel durations typically vary according to both intrinsic (segment-specific) and extrinsic (contextual) specifications. It can be argued that such variations are due to both predisposition and cognitive learning. The present report utilizes acoustic phonetic measurements from Swedish and American children aged 24 and 30 months to investigate the hypothesis that default behaviors may precede language-specific learning effects.

Source generators of mismatch negativity to multiple deviant stimulus types.

The purpose of the present study was to investigate auditory stimulus feature processing and how neural generators might differ among the mismatch negativity (MMN) responses to intensity, frequency, and duration deviant stimuli. Data collected from 72 electrodes in twelve adult female subjects were analyzed. For each subject, peak amplitude and latency values at Fz were compared among responses to the three deviant stimulus types presented in individual conditions with a probability of 0.

Distortion product otoacoustic emissions to single and simultaneous tone pairs.

Distortion product otoacoustic emissions (DPOAEs) evoked by single tone pairs and three simultaneous tone pairs were recorded in 60 normal-hearing adult ears. The purpose was to replicate a previous study using the commercially available probe assembly of the Grason Stadler GSI 60 and including ear of presentation in the statistical analysis along with frequency and condition. DPOAE levels were comparable between ears and conditions, although differences among frequencies were found.

Optimal outcome measures, research priorities, and international cooperation.

The participants in the Eriksholm Workshop on "Measuring Outcomes in Audiological Rehabilitation Using Hearing Aids" debated three issues that are reported in this article. First, it was agreed that the characteristics of an optimal outcome measure vary as a function of the purpose of the measurement. Potential characteristics of outcome self-report tools for four common goals of outcome measurement are briefly presented to illustrate this point.

Expectations about hearing aids and their relationship to fitting outcome.

Clinicians are often concerned that unrealistic prefitting expectations can have a negative impact on fitting success for new, hearing aid wearers. To investigate this concern and to explore the potential value of measuring expectations, we developed the Expected Consequences of Hearing aid Ownership (ECHO) questionnaire as a companion to the Satisfaction with Amplification in Daily Life questionnaire. Four experiments were conducted to (1) determine realistic expectations for hearing aids, (2) evaluate expectations of new users, (3) measure reliability of prefitting expectations, and (4) assess relationships between prefitting expectations and postfitting satisfaction.

Prediction and statistical evaluation of speech recognition test scores.

A speech test evaluation and presentation system is described. The test presentation subsystem has the flexibility and speed of live-voice testing while using recorded test materials. The speech test evaluation subsystem compares an individual subject's test performance on a monosyllabic word test with that of an average person with the same hearing loss.

Outcomes of swallowing rehabilitation in chronic brainstem dysphagia: A retrospective evaluation.

This study examines the functional and physiologic outcomes of treatment in a group of 10 patients with chronic dysphagia subsequent to a single brainstem injury. All patients participated in a structured swallowing treatment program at a metropolitan teaching hospital. This program differs from more traditional swallowing treatment by the inclusion of surface electromyography biofeedback as a treatment modality and the completion of 10 hr of direct treatment in the first week of intervention.

Picture naming of cognate and non-cognate nouns in bilingual aphasia.

Previous research has found differences in the speed and accuracy of responses involving concrete cognate nouns and non-cognate nouns in a range of written and "on-line" tasks using neurologically unimpaired, bilingual adults. The present study investigated whether cognateness affects verbal confrontation naming performance in balanced French/English bilinguals (N = 15 aphasic and 15 non-aphasic subjects). Subjects met selection criteria for equal proficiency, regular use, and early acquisition of both languages.

Solving the mystery of intermittent fluency breaks in a preschool child: chronic stuttering or normal fluency breaks?

The possibility of chronic stuttering is investigated in a preschool boy with a brief history of intermittent fluency breaks. The variability of the behavior adds to the mystery and makes the diagnosis of unusual or stuttering-like fluency breaks particularly difficult. Clues for solving this mystery are obtained from both the child and his parents.

Age-related changes in monosyllabic word recognition performance when audibility is held constant.

Monosyllabic word recognition was studied in 140 subjects between the ages of 20 and 90 years. The subjects were tested under a condition of fixed audibility that was achieved by presenting bandpass-filtered Northwestern University Auditory Test No. 6 (NU-6) word lists at a constant signal-to-noise ratio and limiting threshold losses at the speech frequencies to 25 dB HL.

The effectiveness of the Navy's Hearing Conservation Program.

The purposes of this study were to determine the incidence of significant threshold shift (STS) for a large number of Naval fleet personnel, evaluate hearing conservation program (HCP) compliance for a large number of Naval ships, and determine whether two currently used compliance measures are useful means of evaluating HCP effectiveness. Data were collected from 12,492 medical records of 154 ships/submarines regarding STS incidence and follow-up, percent of valid audiograms, and other HCP elements. Data analyses suggested that STS incidence (29%) and follow-up compliance (62%) among fleet personnel may be too high and low, respectively, although audiogram compliance is 80.

Evaluating relative speech recognition performance using the proficiency factor and rationalized arcsine differences.

This study evaluated two measures that have been used to compare the performance of particular subjects to outcomes predicted by the articulation index (Al). One measure was the proficiency factor, that is, the ratio between the Al derived from a test score and the Al derived from objective measurements of speech and noise spectra. The other measure was the difference between rationalized arcsine transforms of the observed score and the score predicted from the Al.