Papers by Arthur Boothroyd
Ear and Hearing, Dec 1, 1988
Journal of speech and hearing research, Jun 1, 1976
Nasality is widely recognized as a problem in the speech of many deaf people. This paper describe... more Nasality is widely recognized as a problem in the speech of many deaf people. This paper describes one approach to the assessment of that problem and to the development of visual aids to assist in the training of velar control. The approach involves
Journal of the Acoustical Society of America, May 1, 1983
A real-time tactile display of fundamental frequency was constructed. This device accepts a train... more A real-time tactile display of fundamental frequency was constructed. This device accepts a train of pitch-synchronous pulses from a pitch extractor and feeds them to one of eight miniature solenoids. Frequency resolution is approximately 1/3 of an octave over a range of 1 1/2 octaves. With the solenoids spaced by 1/4 in., and the index finger as the tactile input site, psychophysical studies showed excellent discrimination among normal English intonation contours and between normal and abnormal contours. The display is currently being used in a study of sensory aids with deaf children in which auditory, visual, and tactile inputs are being compared.
Journal of Speech Language and Hearing Research, Sep 1, 1988
Nine subjects with prelingually acquired, sensorineural, hearing loss were given a three-interval... more Nine subjects with prelingually acquired, sensorineural, hearing loss were given a three-interval, forced-choice, test of speech pattern contrast perception under two amplification conditions. The first involved adjustment of the low and high frequency outputs of a two-channel Master Hearing Aid to each subject's highest comfortable level, but without compression of the short-term dynamic range of the signal. The second involved the additional compression of a 30 dB input range into the subject's dynamic range of hearing, as measured by the difference between speech awareness threshold and highest comfortable level, in each of the two channels. One of the subjects performed much better with compression than without. Among the other eight, however, there was a small but significant reduction of performance when compression was introduced. It is proposed that the one positive result is due to the increased audibility of speech cues made possible by amplitude compression. It is further proposed that the negative results are due mainly to the distortions of time-intensity cues introduced by amplitude compression. The results suggest that, in terms of potential access to meaningful speech cues, the addition of amplitude compression, to an otherwise optimize signal, is unnecessary, or even detrimental, for most profoundly deaf subjects, but could be beneficial for some.
Journal of the Acoustical Society of America, Apr 1, 1992
Previous studies have shown that normal adults compensate for a bite block at the onset of vowel ... more Previous studies have shown that normal adults compensate for a bite block at the onset of vowel production. It has thus been presumed that auditory feedback plays no role in on-line, speech-motor control. Some investigators have further concluded that while acoustic feedback may play some role, it is not a substantial component in the coordination of reciprocal articulatory movement. The role of auditory feedback is explored in this investigation of compensatory skills in oral subjects with congenital hearing loss. Six severely hearing-impaired and six profoundly hearing-impaired adults were recorded. The stimuli were repetitions of a carrier phrase containing a target word with one of three vowels (/i/, /i/, /ae/) in mixed, randomly selected sequences in four conditions: normal (with hearing aids), masking noise (without hearing aids), bite block (with hearing aids), bite block plus masking noise (without hearing aids). Compensation was measured by comparison of the first three vowel formants of each test condition with those of the normal condition. Formants were acoustically analyzed using LPC techniques. Preliminary data suggest that the first few tokens produced with bite block result in some changes in F0 and loudness. However, there is not convincing evidence of failure of compensation. [This work was supported by NINCDS Grant No. DC00121-29.]
Journal of the Acoustical Society of America, May 1, 1994
Speech perception requires the generation, by the perceiver, of language patterns believed to und... more Speech perception requires the generation, by the perceiver, of language patterns believed to underlie the speech actions of a talker. At any moment, the perceiver’s decisions are based on both direct sensory evidence and indirect contextual evidence. Depending on the perceiver’s prior knowledge and perceptual skill, the value of contextual evidence can contribute 5 to 10 times as much information as sensory evidence in normal conversation. Impaired hearing reduces auditory sensory evidence by its effects on threshold, dynamic range, resolution, and susceptibility to noise, leading to increased dependence on visual and contextual evidence. Hearing aids and cochlear implants offer only partial solutions. Adult-acquired impairments, which affect only sensory evidence, are managed primarily by sensory assistance. Congenital and prelingually acquired impairments, however, also affect acquisition of knowledge and perceptual skill. As a result, sensory assistance, though necessary and important, is only the first step in a comprehensive program of management for hearing-impaired children. In this presentation, the foregoing outline will be supported with empirical data on the sensory capabilities of aided and implanted individuals and on the roles of vision and context in speech perception by the hearing impaired. [Work supported by NIH Grant No. 2PO1DC00178.]
International audiology, 1968
The Hearing journal, Nov 1, 2007
IEEE Transactions on Acoustics, Speech, and Signal Processing, Feb 1, 1985
A wearable device is described which represents the fundamental frequency of voiced sounds as the... more A wearable device is described which represents the fundamental frequency of voiced sounds as the locus of pitch-synchronous vibrotactile stimulation of the skin. The pitch extractor, which accepts inputs from either a microphone or an accelerometer, uses a combination of low-pass filtering and peak detection to generate a square wave whose frequency is half that of the fundamental frequency of the speech signal. Using a shift register and a clock, the first half of each cycle is timed, the result determining which of eight output channels is actuated during the second half. The output transducer array consists of eight miniature solenoids mounted in a small plastic box. The electronics package is worn on a belt and the solenoid array is mounted on the forearm. The system is powered by thee 9 V NiCad batteries and runs for 2 to 3 h between charges. Experiments with normally hearing subjects confirmed that single channel changes of stimulus lo-/ cation can be detected with relative ease. It was also demonstrated that the system permits discrimination among some of the principal intonation contours of English. The potential value of this device in the rehabilitation of hearing-impaired children is currently under investigation.
Journal of Speech Language and Hearing Research, Jun 1, 2010
Purpose-The goal was to assess the effects of maturation and phonological development on performa... more Purpose-The goal was to assess the effects of maturation and phonological development on performance, by normally hearing children, on an imitative test of auditory capacity (On-Line
Journal of Speech Language and Hearing Research, Mar 1, 1984
The goal of these studies was to find out how much of the acoustical information in amplified spe... more The goal of these studies was to find out how much of the acoustical information in amplified speech is accessible to children with varying degrees of sensorineural hearing loss. Context-varying, forced-choice tests of speech perception were presented, without feedback on performance, to orally trained subjects with better ear, three-frequency average hearing losses in the range 55-123 dB HL. As expected, average performance fell with increasing hearing loss. The values of hearing loss at which scores fell to 50% (after correction for chance) were 75 dB HL for consonant place; 85 dB HL for initial consonant voicing; 90 dB HL for initial consonant continuance; 100 dB HL for vowel place (front-back); 105 dB HL for talker sex; 115 dB HL for syllable pattern; and in excess of 115 dB HL for vowel height. Performance on the speech contrast tests was significantly correlated with the intelligibility of the subjects' own speech and with the open-set recognition of phonemes in monosyllabic words, even when pure-tone threshold was held constant.
19 Simulation of Sensorineural Hearing Loss: Reducing Frequency Resolution by Uniform Spectral Sm... more 19 Simulation of Sensorineural Hearing Loss: Reducing Frequency Resolution by Uniform Spectral Smearing Arthur Boothroyd Bethany Mulhearn Juan ... time-domain techniques involving modulation of the speech waveform by low-pass filtered noise (Summers, 1991; Summers ...
Journal of the Acoustical Society of America, Mar 1, 2018
The purpose of the work is to develop a protocol for user self-adjustment of hearing aids and to ... more The purpose of the work is to develop a protocol for user self-adjustment of hearing aids and to determine its efficacy and candidacy. An initial study involved 26 adults with hearing loss. Control of overall volume, high-frequency boost, and low-frequency cut employed prerecorded and preprocessed sentence stimuli. Participants took a speech-perception test after an initial self-adjustment and then had the opportunity to repeat the adjustment. The final self-selected outputs were not significantly different from those prescribed by a widely used threshold-based method (NAL-NL2)—regardless of prior hearing-aid experience. All but one participant attained a speech-intelligibility index of 60%. Previous users of hearing aids, however, did not meet this criterion until after taking the speech-perception test. This work is continuing with the UCSD Open-source Speech-processing Platform which provides real-time, six-band, processing of microphone input from ear-level transducer assemblies. This system provides a more realistic participant experience, finer control of level and spectrum, and places no limits on the speech materials used for self-adjustment and outcome assessment. Ongoing work investigates the need for the speech-perception test as part of the self-adjustment protocol and the importance of the level and spectrum from which users make their initial adjustments.
Journal of the Acoustical Society of America, May 1, 1984
The goals were to test two equations reflecting the effects of lexical redundancy on recognition ... more The goals were to test two equations reflecting the effects of lexical redundancy on recognition probability, and to derive typical values for constants appearing as parameters in these equations. pc = 1 − (1 − pi)k, where pc and pi are recognition probabilities with and without lexical redundancy, and pw = pp, where pw and pp are the recognition probabilities for whole words and phonemes within words, respectively. Using phonemically balanced lists, word and phoneme recognition was measured, in normally hearing subjects, at four S/N levels and five word-frequency levels. Analysis of variance confirmed that j and k were relatively independent of S/N ratio, but highly dependent on word frequency. Values of j ranged from 3.1 for nonsense words to 2.3 for high-frequency words. Values of k were 1.3 for phoneme scores and 2.3 for word scores. These data confirm earlier findings indicating that phoneme scores are less influenced by lexical redundancy than are word scores. They also support the model underlying the theoretical equations and provide a means of predicting one type of score from another. [Work supported by PSC. CUNY Award ♯6-63137.]
PubMed, 1986
Lipreading performance, after brief training, was measured in two normal subjects, as the percent... more Lipreading performance, after brief training, was measured in two normal subjects, as the percentage of words recognized in sets of unrelated sentences. Three receptive conditions were used: lipreading alone, lipreading plus a single-channel tactile display of fundamental frequency (temporal only), and lipreading plus a multichannel, tactile, spatial display of fundamental frequency (temporal-spatial). After training, performance with tactile supplements was better than without, but it was not possible to conclude that either of the tactile displays was better than the other. During training, a significant correlation between performance and session number was found for the temporal-spatial display only.
Ear and Hearing, 2019
Objective-The objective was to determine self-adjusted output response and Speech Intelligibility... more Objective-The objective was to determine self-adjusted output response and Speech Intelligibility Index in individuals with mild to moderate hearing loss and to measure the effects of prior hearing-aid experience. Design-Thirteen hearing-aid users and 13 non-users, with similar group-mean pure-tone thresholds, listened to pre-recorded and pre-processed sentences spoken by a man. Starting with a generic level and spectrum, participants adjusted i) overall level, ii) high-frequency boost iii) lowfrequency cut. Participants took a speech-perception test after an initial adjustment before making a final adjustment. The three self-selected parameters, along with individual thresholds and Real-Ear-to-Coupler Differences, were used to compute output levels and Speech Intelligibility Indices for the starting and two self-adjusted conditions. The values were compared with a thresholdbased prescription (NAL-NL2) and, for the aid-users, performance of their existing aids. Results-All participants were able to complete the self-adjustment process. The generic starting condition provided outputs (between 2 and 8 kHz) and SIIs that were significantly below those prescribed by NAL-NL2. Both groups increased SII to values that were not significantly different from prescription. The aid users, but not the non-users, increased high-frequency output and SII significantly after taking the speech-perception test. Seventeen of the 26 participants (65%) met an SII criterion of 60% under the generic starting condition. The proportion increased to 23 out of 26 (88%) after the final self-adjustment. Of the 13 hearing-aid users, eight (62%) met the 60% criterion with their existing aids. With the final self-adjustment 12/13 (92%) met this criterion. Conclusions-The findings support the conclusion that user self-adjustment of basic amplification characteristics can be both feasible and effective with or without prior hearing-aid experience.
PubMed, 1988
An adult with a severe, postlingually-acquired, sensorineural, hearing loss was given 2 hours a w... more An adult with a severe, postlingually-acquired, sensorineural, hearing loss was given 2 hours a week of training in the perception of connected discourse by lipreading, supplemented by voice fundamental frequency (Fo), encoded as locus of vibratory stimulation of the forearm. Three, 3-week blocks of training in the supplemented condition were interspersed with 1-week periods of training by lipreading alone. Training was conducted via a computer-controlled, interactive video system, using a semi-automated connected discourse tracking procedure. Performance was measured as the percentage of words correctly recognized on the first presentation of new sentence material. Scores by lipreading alone averaged approximately 65 percent and remained essentially constant over the 13 weeks of training. Scores under the supplemented condition rose from 65 percent at the beginning of the study to 85 percent at the end. The final supplemented score represented roughly a 50 percent reduction of error rate, when compared with lipreading alone. Performance with the tactile supplement was not as good as with auditorily presented Fo, but was better than has previously been reported in the literature. These data provide evidence to support the notion that subjects can learn to integrate novel tactile codes with the visual stimulus during the lipreading of connected speech.
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Papers by Arthur Boothroyd