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A P Benguerel

Publications and source records attributed to A P Benguerel.

11 recordsLinked to original sources
PubMed1991

The design of CAST (Computer-Aided Speechreading Training).

The underlying theoretical assumptions, goals, design, and implementation of a Computer-Aided Speechreading Training system (CAST) are described as a case study in program design. This computerized speechreading assessment and training system simulates face-to-face intervention and is designed to be one component of a comprehensive aural rehabilitation program for preretirement adults with acquired mild-to-moderate hearing loss. The interactive, automated course consists of eight training lessons, each focusing on a particular viseme that is practiced by a modified discourse tracking method using viseme-specific texts. Three basic speechreading skills are emphasized: visual speech perception, use of linguistic redundancy, and use of feedback between message sender and receiver. These skills are evaluated separately by means of CAST tracking rate, receiver strategy, and inferred error type. Four example case assessments are provided to illustrate the potential applications of CAST as a standardizable rehabilitative tool. An independent program evaluation is provided in a companion paper (Gagné, Dinon, & Parsons, 1991). Comparisons between CAST, face-to-face tracking procedures, and natural discourse are presented and discussed with reference to theoretical and clinical issues in speechreading and program evaluation.

Computer-Assisted Instruction↗
PubMed1989

The effect of coarticulation on the role of transitions in vowel perception.

Sequences of the form V1bV2bV1 were recorded by a male speaker. From each sequence, three types of stimuli were edited out: (1) the medial vowel, from after the burst of the preceding stop to the start of the closure of the following stop; (2) the quasi-steady state of the medial vowel, and (3) the transitions alone of the medial vowel (complement to 2). The perception of each type of stimulus was examined in separate tests and the results were compared. For two of the three contexts (V1 = /i/, /u/), scores for stimuli of the third condition (transitions) were as high as for the first (control) condition, supporting the importance of transitions as cues for vowel identity. For the third context (/a/), however, performance was significantly lower, thus suggesting an influence of vowel context on the contribution of transitions to vowel identification.

Cues↗
PubMed1989

[Interactive Microcomputer Method of Lipreading (MIMILLE): an interactive microcomputerized method of lipreading].

A computer-aided speechreading assessment and training system is presented. It is intended to be one component of a comprehensive aural rehabilitation program for preretirement adults with acquired mild-to-moderate hearing loss. Each lesson focuses on a different viseme which is practiced using the 'discourse tracking' method. The system allows the evaluation of the basic skills necessary for lipreading, i.e. good visual speech decoding and effective use of lingustic redundancy and transmitter feedback, by evaluating separately tracking rate, strategy, and types of errors.

Algorithms↗
PubMed1982

Coarticulation effects in lipreading.

Normal-hearing and hearing-impaired subjects with good lipreading skills lipread videotaped material under visual-only conditions. V1CV2 utterances were used where V could be /i/, /ae/ or /u/ and C could be /p/, /t/, /k/, /ch/, /f/, /theta/, /sh/, /sh/ or /w/. Coarticulatory effects were present in these stimuli. The influence of phonetic context on lipreading scores for each V and C was analyzed in an effort to explain some of the variability in the visual perception of phonemes which was suggested by existing literature. Transmission of information for four phonetic features was also analyzed. Lipreading performance was nearly perfect for /p/, /f/, /w/, /theta/ and /u/. Lipreading performance on /t/, /k/, /ch/, /s/, /i/ and /ae/ depended on context. The features labial, rounded, and alveolar or palatal place of articulation were found to transmit more information to lipreaders than did the feature continuant. Variability in articulatory parameters resulting from coarticulatory effects appears to increase overall lipreading difficulty.

Correction of Hearing Impairment↗
PubMed1980

Hindi stop consonants: an acoustic and fiberscopic study.

Fiberscopic films and audio recordings were made of two native speakers of Hindi, producing # Ci, iCi, iC # utterances where C was one of the four types of stops and affricates. The voiced unaspirated type showed voicing through the whole consonant and no ab-/adduction gesture. The other three types, in the intervocalic case, all showed an ab-/adduction gesture, but the timing and the amplitude of this gesture differed for the three types. For the voiceless unaspirated type, the gesture started at the beginning of the consonant and ended at the release, whereas for the voiced aspirated type, it started at the release and ended at the end of the consonant. For the voiceless aspirated type, it started and ended with the consonant, reaching a glottal width approximately double of the latter two types. Similar results were obtained in initial and final position. Voice onset time values and durations of oral closure are examined. Pros and cons of the terms 'voiced aspirated', 'murmured aspirated', and 'voiced phonoaspirated' are discussed. Finally a mechanism underlying stop production is suggested.

Adult↗
PubMed1976

Perception of coarticulated lip rounding.

This study investigates the perceivability of coarticulated lip rounding in French. Nine utterances containing the clusters /kstr/, /rstr/, and /rskr/ followed by one of the vowels /i/, /y/, or /u/ in all possible combinations, were truncated at 4 different points before the vowel. Test items in each of the 4 groups therefore contained different amounts of information regarding the nature of the following vowel, due to coarticulatory influences of the vowel on the preceding consonants. Subjects were asked to predict the identity of the missing vowel. Results show that when segments up to and including at least half of the final consonant of the cluster are present, subjects correctly identify the missing vowel well above chance level. Several individuals were able to identify the vowel even when presented with shorter versions of the utterances. No significant difference in performance was found between French and English subjects, nor between subjects with and without phonetic training. Pereceivability of individual features of the missing vowel is discussed. It is concluded that coarticulatory effects due to lip rounding (as well as to horizontal place of articulation) provide perceivable information at a level significantly above chance, and that this information may be used by the perceptual mechanism as an aid in speech sound identification.

Adult↗