Brenda H. Whitehead

Vibratory patterns of the vocal folds during pulse register phonation

The purpose of the present study was to investigate the vibratory patterns of the vocal folds during pulse register phonation. Glottal area-time functions were calculated from three high speed laryngeal films (4000 frames/second) obtained during phonation of the schwa vowel in pulse register by a normally hearing and speaking adult female. The results for the first film indicated that each of 35 consecutive vibratory cycles of the vocal folds consisted of a single opening/closing gesture followed by a lengthy closed phase. The analysis of the second film revealed that each of 33 consecutive vibratory cycles consisted of a double opening/closing vocal fold pattern, followed by a long closed phase. For the third film, the results indicated that each of 26 consecutive vibratory cycles of the vocal folds consisted of either a double or triple opening/closing gesture followed by a lengthy closed period. From these data, it appears that one of the physiological descriptors of pulse phonation is multiple, as well as single, vocal fold vibratory patterning.

Effect of vowel environment on fricative consonant duration in speech produced during simultaneous communication

This study investigated the effect of vowel environment on fricative consonant duration in contextual speech produced during simultaneous communication (SC). Previous studies (Schwartz, 1969) of vowel influences on consonant duration supported the notion of anticipatory scanning, in which final vowel targets influence the duration of preceding fricative consonants. Ten normal-hearing, experienced sign language users recorded palatal and alveolar fricatives produced in four vowel environments in contextual sentences under SC and speech-only (SO) conditions. Results indicated longer sentence durations for SC than for SO, and significant effects of vowel context on fricative consonant duration in contextual speech in both SC and SO conditions that revealed similar anticipatory scanning effects as seen in previous studies. These data confirm previous research indicating that the temporal alterations produced by simultaneous communication do not involve violations of the temporal rules of English speech.

Effect of sign task on speech timing in simultaneous communication

The purpose of this investigation was to study the effect of the signing task on temporal features of speech during simultaneous communication (SC). The effects of three independent variables: (a) communication mode (speech only vs. SC); (b) sign task demand (base vs. elaborated signs); and (c) type of sign movement (kinetic vs. morphokinetic) were studied on five dependent variables: (a) word duration; (b) sentence duration; (c) diphthong duration; (d) interword interval before signed experimental word (IWIB); and (e) interword interval after signed experimental word (IWIA). Audio recordings were made of 12 normal hearing, experienced sign language users speaking experimental words that varied in sign task demand and movement under SC and speech only (SO) conditions. Results indicated longer sentence durations for SC than SO and longer anticipatory durations of IWIB and diphthong before signed words, especially those using signs with greater task demand or with movements including hand shape change. IWIA only lengthened for SC vs. SO with no further effect of sign task demand or movement. These results indicate finite effects of sign task demand and movement on pause and segment durations before the sign but not as strong an effect as has been reported for increased finger spelling task length.

Production and Perception of Final Consonant Voicing in Speech during Simultaneous Communication.

Simultaneous communication combines both spoken and manual modes to produce each word of an utterance. This study investigated the potential influence of alterations in the temporal structure of speech produced during simultaneous communication on the perception of final consonant voicing. Experienced signers recorded words that differed only in the voicing characteristic of the final consonant under two conditions: (a) speech alone and (b) simultaneous communication. The words were digitally edited to remove the final consonant and played to 20 listeners who, in a forced-choice paradigm, circled the word they thought they heard. Results indicated that accurate perception of final consonant voicing was not impaired by changes in the temporal structure of speech that accompany simultaneous communication.

Sentence intonation and syllable stress in speech produced during simultaneous communication.

This study investigated prosodic variables of syllable stress and intonation contours in contextual speech produced during simultaneous communication (SC). Ten normal-hearing, experienced sign language users were recorded under SC and speech only (SO) conditions speaking a set of sentences containing stressed versus unstressed versions of the same syllables and a set of sentences containing interrogative versus declarative versions of the same words. Results indicated longer sentence durations for SC than SO for all speech materials. Vowel duration and fundamental frequency differences between stressed and unstressed syllables as well as intonation contour differences between declarative and interrogative sentences were essentially the same in both SC and SO conditions. The conclusion that prosodic rules were not violated in SC is consistent with previous research indicating that temporal alterations produced by simultaneous communication do not involve violations of other temporal rules of English speech.

Perception of final consonant voicing in speech produced during simultaneous communication

The temporal structure of speech is altered dramatically when a person uses sign language and speaks aloud simultaneously (i.e., simultaneous communication or SC). Notable among these temporal alterations are durational increases of vowels, pause times between words, and voice onset times. Temporal aspects of speech play a pivotal role in the perception of certain phonemic contrasts in spoken English. For example, cues for the perception of final consonant voicing are carried in the vowel that precedes the final consonant. The purpose of the present study was to investigate the effect of increased segment durations associated with speech produced during SC on final consonant voicing perception. Eight skilled SC users produced naturally spoken words that differed only in the voicing characteristic of the final consonant. The words were recorded under two conditions: (a) speech alone and (b) SC. Digital editing was used to remove the final consonant. The digitally altered words were played to 20 listeners w...

Sentence intonation and syllable stress in speech produced during simultaneous communication

This study investigated prosodic variables of syllable stress and intonation contours in contextual speech produced during simultaneous communication (SC). Ten normal-hearing, experienced sign language users were recorded under SC and speech only (SO) conditions speaking a set of sentences containing stressed versus unstressed versions of the same syllables and a set of sentences containing interrogative versus declarative versions of the same words. Results indicated longer sentence durations for SC than SO for all speech materials. Vowel duration and fundamental frequency differences between stressed and unstressed syllables as well as intonation contour differences between declarative and interrogative sentences were essentially the same in both SC and SO conditions. The conclusion that prosodic rules were not violated in SC is consistent with previous research indicating that temporal alterations produced by simultaneous communication do not involve violations of other temporal rules of English speech.

Effect of sign complexity on speech timing in simultaneous communication

Simultaneous communication combines spoken English with manual representations of English words by signs and fingerspelling. The purpose of this investigation was to study the effect of sign complexity on temporal features of speech during simultaneous communication (SC). The effects of three independent variables: (a) mode (speech only versus SC); (b) sign complexity (base versus elaborated signs); and (c) type of sign movement (kinetic versus morphokinetic) were studied on five dependent variables: (a) word duration, (b) sentence duration, (c) diphthong duration, (d) interword‐interval before signed experimental word (IWIB), and (e) interword‐interval after signed experimental word (IWIA). Audio recordings were made of 12 normal‐hearing, experienced sign language users speaking experimental words that varied in sign complexity and movement under SC and speech only (SO) conditions. Results indicated longer sentence durations for SC than SO and longer anticipatory durations of IWIB and diphthong before si...

Speech during simultaneous communication: Temporal characteristics and perceived naturalness

Simultaneous communication is a process which combines spoken English with various manual representations of English words in the form of signs and fingerspelling. The present study investigated the durational characteristics and perceived naturalness of speech produced during simultaneous communication with increasing fingerspelling complexity. Ten normal‐hearing adult females, skilled in the use of simultaneous communication, served as speakers. Experimental words of differing fingerspelling complexity were embedded in sentences which were: (a) spoken and (b) spoken and signed, except for the experimental words which were fingerspelled. Five temporal measures of speech were calculated: (a) sentence duration, (b) experimental word duration, (c) diphthong duration preceding the experimental word, (d) pause duration preceding the experimental word; and (c) pause duration following the experimental word. Speech naturalness was rated using a nine‐point naturalness rating scale for all stimulus samples. Resul...

Vowel durational characteristics daring simultaneous communication

The purpose of this investigation was to study vowel durations during speech produced simultaneously with sign language and fingerspelling and to determine whether final consonant influences on vowel durations, which occur naturally in speech, also occur in speech produced during simultaneous communication. Vowel durations were obtained for the vowels /ɑ/, /ɪ/, and /ae/, which were embedded in CVC words in which the final consonant was systematically varied. All CVCs met the criteria of having a common sign and of being phonetically and orthographically correlated. The CVCs were embedded in a carrier phrase and were uttered by ten normally hearing speakers fluent in sign language, under conditions of: speech, speech combined with sign language, and speech combined with signing of the carrier phrase and fingerspelling of the CVC. Results indicated that vowels produced with accompanying sign language and fingerspelling were significantly longer in duration than those produced during speech alone. Further, it...