A case report of within-vowel glottal stop insertion in the speech of an adult male

.1 . FLUENCY DISORD . 16 (1991), 55-69

A CASE REPORT OF WITHIN-VOWEL GLOTTAL STOP INSERTION IN THE SPEECH OF AN ADULT MALE DONALD E . MOWRER Arizona State University

CARLENE FAIRBANK Scottsdale PaGlic Schools

The subject of this case study, a self-supporting 35-year-old man with a history of neurogenic and psychogenic disorders, displayed an unusual speech dysfluency consisting of frequent within-vowel interruptions (broken words) that often occurred in the word-final position of a phrase or clause . An analysis of the frequency of the dysfluencies occurring during 19 different speaking conditions revealed that the vowel interruption dysfluency ranged from 9% to 19% (M = 13 .32% : SD = 3 .35%) of the words spoken during 16 speaking conditions in which stuttering behaviors are known to decrease . The dysfluency rarely occurred during three speaking conditions, namely, whispered speech (reading or monologue), and reading a passage in which dysfluent words from a previous reading had been omitted . Numerous prosodic deviations were observed that contributed to his atypical speech pattern . The nature of this vowel-interruption dystuency and his atypical speech pattern are discussed and compared with the neurogenic stuttering syndrome .

Almost without exception, every speech/language pathologist at some time in his/her career encounters an individual whose speech is so atypical that it seems not only unique to that individual but also appears to defy categorization . Descriptions of several such atypical communication disorders have been published as case studies (Critchley, 1970 ; Deal, 1982 ; Van Lancker, Bogen, and Canter, 1983) . Ventry and Schiavetti (1980) point out several benefits that case reports offer the professional community . The benefits range from illustrating important principles that might be overlooked in group data to providing valuable insight into the use of certain clinical or research techniques . Through careful documentation and description of atypical communication disorders, we maybe able to expand our knowledge of human communication and enhance our ability to diagnose and treat certain types of atypical communication disorders. Address correspondence to Donald Mowrer, Department of Speech & Hearing Science, Arizona State University, Tempe, AZ, 85287 . © 1991 by Elsevier Science Publishing Co . . Inc . 55 655 Avenue of the Americas, New York . NY 10010 0094-730X/91/$3 .50



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D. E. MOWRER and C. FAIRBANK

The subject of this report is an individual whose dysfluent speech consisted solely of a vowel interruption that was unlike any speech disorder reported in the literature or known by the author or his associates . The only references to the use of within-vowel glottal stop insertion as a dysfluency is the within-vowel hesitation experienced by some individuals who stutter . Johnson (1961) referred to this dysfluency as a broken word : Van Riper (1982) called it a medial gap . Starkweather (1987) describes a broken word as a condition " . . . in which the vowel is begun, then cut off abruptly by a tight closure of the glottis, then reinstated . The tension of the tightly shut glottis is evident both from the abrupt termination of the voice and from the quality of the subsequent reinitiation of the vowel" (p . 148) . Interestingly, a similar linguistic feature, internal hiatus, is used in some languages to indicate that the initial vowel arrests the first syllable whereas the second vowel releases the following syllable (Pei and Gaynor, 1954) . For example, the Hawaiian word tnoana is pronounced [nto7ana] . The transition from /oI to /a/ is interrupted with a glottal stop . The English speaker typically inserts a glide between two adjacent vowels . Although the stutterer's broken word may sound like an example of internal hiatus, the break is not used for linguistic purposes : its use may reflect muscular tension due to emotional or possibly physiological conditions . The author initially conversed with H .T ., the 35-year-old man described in this study, when seeking directions to a nearby nursing home . The author noted H .T . 's unusual speech and arranged an interview with him . The subject neither requested assistance to improve his speech nor was concerned about the unusual nature of his speech pattern . Permission was granted to gain access to H .T .'s medical records kept by the local guidance clinic where he was enrolled as an outpatient, to interview his sister, and to review records kept by the local school . A review of the information gleaned from these sources is presented in the case history reported below . It should be noted that while the records contained considerable pertinent information, it is fell that these records were incomplete and insufficient to allow for an adequate diagnosis of H.T .'s speech deviation . CASE HISTORY The review of the medical records indicates the presence of a long-standing history of neurogenic and psychogenic disorders . According to the mental health clinic's case history report, complications occurred before and during H .T .'s birth that may have resulted in brain damage (attempted drug-induced abortion and anoxia at birth) . During H .T . 's preschool years, motor and speech development were severely delayed . He was labeled as mentally retarded . At age 7, it was reported that his speech



VOWEL INTERRUPTION

57

was difficult to understand because of language, articulation, and fluency problems . He received speech therapy during two years in elementary school but his progress was described as slow . His academic progress was described as minimal through the sixth grade . At age 17, H .T .'s reading level was rated at the grade 2 .6 level, his mathematical ability was rated at grade level 6 .1, and his IQ was 79 using the Slosson Intelligence Test . The Bender-Gestalt test revealed soft signs of neurological impairment, emotional disturbance, and obsessive-compulsive tendencies . He was described as withdrawn, socially inept, and immature . He spoke with an elevated pitch and evidenced some articulation problems . Rate, quality, and rhythm aspects of speech were described as deviant . Although he was considered for placement in a mental institution, he was placed in a high school special education class . Upon completion of high school (age 22), his reading level had increased to grade 5 .3, mathematical ability increased to grade 7 .0, and he obtained a score of 97 on the Wechsler Adult Intelligence Tcst . He scored 85 on the GATE intelligence test . The Bender-Gestalt test again revealed signs of neurological impairment plus severe emotional difficulties . The Rorschach test revealed no psychosis although extreme social and emotional deprivation, a sterile family life, and lack of affect were noted . He was diagnosed as a social isolate with paranoid schizophrenic tendencies, and was considered untrainable and unemployable . While there is no record of an attempt to assess H .T .'s neural function, reports of the prenatal abortion attempt, anoxia at birth, delayed motor and language development, and early difficulties in school indicate that H .T . may have suffered from early brain damage . When evaluated by the authors, H .T, was self-sufficient, lived alone, operated an automobile, and maintained several part-time jobs, one of which was repairing TV sets . He received 1 to 2 hr of counseling per week at a local mental health clinic . He was polite, cooperative, and willing to perform any task asked of him during the speech examination . PRELIMINARY TESTING During the interview, eight tests were administered to. assess H .T .'s articulation, hearing acuity, ability to sustain phonation, oral structure and function, apraxia of speech, occurrence of dysfluencies, speech rate, and attitudes toward speaking situations . Deviances from the norm were noted in only three areas : I) number and type of dysfluencies, 2) attitudes toward speaking situations, and 3) speech rate . Results of the Stuttering Interview, Form H (Ryan, 1974) indicated a mean rate of 9 .6 dysfluencies per min, slightly above the mean of 9 .2 stuttered words per min obtained from Ryan's sample of 20 male stutterers ages 13-43 . All of the dysfluencies consisted of what Johnson (1961) re-



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D . E . MOWRER and C . FAIRBANK

ferred to as broken words or more accurately, within-vowel glottal stop insertion . Analysis of the answers to questions from Eriekson's (1969) S-scale revealed that 25 (64%) of H .T .'s 36 answers agreed with answers given by stutterers . The score of 25 corresponds with the mean of 24 .65 obtained by Erickson's group of50 stutterers . When asked if he was concerned about his speech, he stated that he was aware that he "broke up" words but was not disturbed about his speech . There was no overt evidence of anxiety associated with his speech dystluency nor was there evidence of accessory behaviors that occurred during dysfluencies . These accessory behaviors are often observed among many individuals who stutter . His speech appeared to be produced in an effortless fashion . He made no apparent attempts to avoid dysfluencies . H .T .'s mean speech rate during monologue was 101 .5 wpm (2 .00 sps) and when reading, the mean rate was 100 .0 wpm (1 .85 sps) . These speech rates are considerably below the norm for average adult male speakers (4 .97 sps during monologue) as reported by Miller . Grosjean, and Lomanto (1984) . DESCRIPTION OF THE VOWEL INTERRUPTION DYSFLUENCY The vowel interruption dystluency observed in H .T .'s speech can be described as follows : The vowel in a CVC or CCVC monosyllabic word is arrested by a glottal stop followed by a reduplication of the previous vowel, which serves to release the final consonant . Thus, the monosyllabic word is produced as a bisyllabic word separated by a glottal stop . For example, /hom/ is produced as Iho'2 oml . Ten dysfluent words, randomly selected from an extemporaneous speaking condition, were transferred to digitized signals sampled at 10,000 samples per sec using a 12-hit analogue-to-digital converter (Data Translation Model DT 3382) and stored for analysis by a Digital Equipment Corporation PDP 11-23 computer . Graphics editing software was used to identify and measure elapsed time from termination of the first vowel to onset of the second vowel . Mean pause duration between vowels contained in the Ill selected words was 101 .5 msec (SD = 38 msec ; range 47-143 msec) .'[he dystluent word home, is shown graphically in Figure I . Note that the amplitude of the duplicated vowel is about one-half as great as the preceding vowel amplitude . This amplitude difference was typical of vowels in the other nine samples . A spectrogram, recorded using a Kay Sonagraph Model 5500, of the word grass is shown in Figure 2 . The duration of the first syllable )grx] is 214 msec . It is terminated with a glottal stop lasting for 97 msec and



59

VOWEL 1NTERRUPTION

[ho

2

o

nil

Figure 1 . Wave form of the vowel-interruption dystluency in the word home .

Figure 2 . Spectrogram of /gra° s/ spoken as [grs 2 a s] .

Ii

:: : h

9~1P,

! Jd~uulr !~ TI

,GUI



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D . E . MOWRER and C . FAIRBANK

Mln ''(,Jr1"

i n

u

l l

I

II'

sAaea

[

w Figure

3.

Spectrogram of /wa'k/ spoken as

[way a• k1 .

followed by Re sJ, which completes the syllable . Considerable laryngeal tension was noted during initiation of the second vowel in that the frequency of the initial second vowel [x] is higher than the final section . This frequency shift is more visible in the expanded spectrogram of the word work shown in Figure 3 . All 10 dysfluent words analyzed using the Kay Sonagraph revealed a similar pattern .

ANALYSIS OF THE OCCURRENCE OF VOWEL INTERRUPTIONS AMONG 19 SPEECH SAMPLES In an attempt to determine the effect different speaking conditions might have on the frequency and location of the dysfluency, speech samples were collected during 19 different speaking conditions, 17 of which are known to decrease the frequency of dysfluencies among individuals who stutterer (Ingham, 1984) . Seven speaking conditions included speaking extemporaneously and seven conditions consisted of reading aloud . The seven common speaking conditions were : 1) speaking while tapping the finger at approximately 90 beats per min, 2) speaking while both ears were masked at 85 dB, 3) speaking in a falsetto register, 4) speaking at a slow rate, 5) speaking while whispering, 6) speaking under conditions of delayed auditory feedback (DAF), and 7) speaking to the examiners .



VOWEL INTERRUPTION

61

In addition to these 14 speaking conditions (seven speaking extemporaneously and seven reading aloud), data were collected from five other speaking conditions : 1) counting aloud from 1 to 10, 2) reading aloud simultaneously with an examiner (choral reading), 3) reading the same passage aloud five consecutive times (adaptation), 4) reading aloud from a passage in which dysfluent words from a previous reading were eliminated, and 5) singing four songs . Speech samples were selected from the first 100 words spoken in eight of the speaking conditions . Eleven speech conditions contained less than IW words . The final corpus comprised 1,967 spoken words . Duration of the speech samples ranged from 4 .7 to 124 sec . Speech samples were recorded using a JVC Stereo Cassette recorder (Model RC-575JW) with the microphone placed approximately 20 inches from the subject's mouth . Recording took place in the presence of the authors at the home of H .T . 's friend during a 2-hr period . A transcript of the tape-recorded speech samples was prepared by each author independently . The two scripts were compared and where disagreement occurred, both authors jointly reviewed the taped samples until agreement was reached . The authors independently circled each word that contained an instance of a vowel interruption dysfluency, assigned the dysfluent word to a grammatical category, and identified its position in the utterance (initial-, medial-, or final-word) in a phrase or clause . Tally sheets were compared and when disagreements occurred, a third evaluator (a linguist) decided which category to use . A Bruel and Kjaer level recorder (type 2305) was used to produce a graphic record of acoustic energy of syllables displayed as amplitude over time . Data were recorded on graph paper lined in increments of I dB . Paper speed was 30 mm per sec . This graphic representation permitted accurate identification of the amplitude peaks of each spoken syllable . An utterance was defined as a group of spoken words separated by an unfilled pause of 250 msec or more (Goidman-Eisler, 1968) . Utterance length was determined by measuring the distance between initial syllable onset (initial rise in amplitude) and the completion of the terminal syllable of the utterance . Pause intervals were determined by measuring the distance from termination of a syllable to initiation of the following syllable . Syllable intensity levels were determined by measuring the relative decibel increase from syllable onset to syllable termination . The number of words sampled in each speaking condition, as well as number of syllables sampled, duration of the sample, number of dysfluencies in the sample, percentage of dysfluencies, and rate of speech in syllables per second are shown in Table 1 .



D . E . MOWRER and C . FAIRHANK

62

Table 1 . Number of Words and Syllables Analyzed, Duration of Speech . Number and Percentage of Dystuent Words, and Speech rate Is/s) in Each of 23 Speaking Conditions Speaking condition

Words analyzed

Syllables analyzed

Duration in sec

Dyslluent words

Rhythm Ht Rhythm Rt Masking E Masking R H . Pitch F H . Pitch R Slow R Slow R Whisper E Whisper R DAF E DAF R Normal E Normal R Counting Choral Omit Words Singing Adapt . I Adapt . 2 Adapt . 3 Adapt . 4 Adapt . 5 Totals

75 86 75 100 95 98 65 97 100 100 72 100 44 100 10 100 50 100 100 100 100 100 100 1967

78 88 79 105 109

47 60 52 58 59 52 108 133 54 51 72 108 26 60 5 80 43 80 62 58 58 58 59 1443

10 17 II 12

G* = R* =

III)

77 103 120 104 80 102 52 III 11 102 59 124 109 107 107 108 108 2149

9

9 II 11 0 0 8 9 8 17 I 18 I 11 13 18 16 17 17 244

Percentage of words dysfluent

Rate

0 .13 0 .19 t) .l4 0 .12 0 .09 0 .09 0 .16 0 .11

.165 1 .46 1 .51 1 .81 1 .77 2 .11 0 .71 0 .77

11 .011

222

0 .00

2 .03

Is/sl

0 .11

1 .11

0 .09 0 .18 0 .17 0 .10 0 .18 0 .02

0.94 2 .00 1,85

0 .11

0 .13 11 .18 0 .16 0 .17 0 .17

1 .27 137 1 .55 1 .75 1 .84 1 .84 1 .86 1 .83

extemporaneous speaking. reading .

Frequency of the Vowel Interruption Dystluency A total of 244 (12 .4 .%) words contained vowel interruptions in the corpus of 1,967 spoken words . The percentage of dysfluent words was lowest during three speaking conditions, namely, whispering while reading and during extemporaneous speaking (0%), and reading a passage in which dysfluent words that occurred during a prior reading were omitted (2%) . Among the 16 remaining speaking conditions , the percentage of dysfluent words ranged from 9% to 19% . Inspection of the spectrograms depicting 10 words that seemed to have very slight hesitations within the vowel revealed that the duration of these hesitations was less than 50 cosec, too small for listeners to classify as dystluencies . In summary, the 244 dysfluencies reported in this analysis represent only the listener-identified instances of perceived vowel interruptions produced with excessive laryngeal tension .



VOWEL INTERRUPTION

63

Adaptation Effect As shown in Table 1, there was no evidence of an adaptation effect while reading the same 100-word passage five times in succession . The frequency of dysfluent words never fell below 13 during successive readings (range = 13-18 dysfluent words) . During the five readings of the same passage, eight (32%) words contained dysfluencies during all five readings, eight words contained vowel interruptions in four readings, one word contained vowel interruptions during three readings, and eight words contained vowel interruptions in only one of the readings . Because 64% of words containing vowel interruptions occurred during four and five readings of the same passage, a high degree of consistency among certain words containing vowel interruptions is indicated .

Word Position Effect The number of words containing vowel interruptions occupying the finalword position of a phrase or clause were compared with the number of words containing vowel interruptions in locations other than final-word positions . Single-word utterances were omitted . During 13 speaking conditions (counting, choral reading, word avoidance, adaptation, whispering while reading, and speaking extemporaneously were omitted) vowel interruptions occurred in the final-word position of a phrase or clause 114 times out of 146 (78%) . It was noted that words in the final position were frequently stressed . Stressed words in other positions also contained vowel interruptions . Word stressing rather than word position seemed to be the critical factor signaling vowel interruptions . Grammatical Function Effect Of the 244 words containing vowel interruptions, three-fourths occurred in nouns (51%) and verbs (27%) . Only a few dysfluencies occurred within pronouns, adverbs, adjectives, or prepositions . Conjunctions or articles never contained vowel interruptions . Because nouns and verbs are parts of speech that frequently receive stress in English, it is not surprising to find that these grammatical classes contained most vowel interruptions .

Voluntary Control Effect H .T . described his unusual pronunciation of some words as "breaking words in half." The examiner asked H .T . to tell a story and refrain from breaking words . If a vowel interruption occurred, the examiner said, "No,



64

L) . E . MOWRER and C . FAIRBANK

you broke that word . Say it like this ." A model of the correct production was presented . While speaking 10 sentences extemporaneously, he produced 18 words containing vowel interruptions . He was able to produce the dysfluent word without the vowel interruption on his second attempt in all but two instances in which a third trial was required before it was spoken fluently . Thus, he was able to demonstrate a degree of voluntary control over the vowel interruption when instructed to do so . A change in the vowel F o was observed in the corrected words that previously contained a vowel interruption . As an example, the F„ of the vowel /o/ in the corrected word "home" was analyzed . Although he produced [ho : ml as one syllable, the vowel F u was increased throughout its production (an increase in F o from approximately 138 Hz at vowel onset to 195 Hz at vowel termination) . It appeared as though laryngeal tension, although present as indicated by the rise in the vowel F0 was sufficiently suppressed to inhibit the glottal stop . Speaking Conditions that Result in a Decrement of Vowel Interruptions While the frequency of the vowel interruptions varied from 9% to 19% during 16 of the speaking conditions, vowel interruptions did not occur while whispering during either extemporaneous speaking or reading conditions, and occurred on only 2% of the words spoken during the speaking condition in which previous words containing vowel interruptions were omitted . Most individuals who stutter also have been observed to speak without dysfluencies when whispering (Adams, 1955 ; Johnson and Rosen, 1937 ; Perkins, Rudas, Johnson, and Bell, 1976) . Brown and Brands (1971) and Parnell, Amerman, and Wells (1977) note that rate of speech decreases considerably during whispered speech, but in H .T .'s case, rate of speech increased while whispering partly because the vowel-interruption dysfluency was eliminated . Kallail and Emanuel (1984) in their study of phonated and whispered vowels produced by 15 adult males, found that three acoustical changes take place during whispering : l) significant rise in the frequency of the first vowel formant, 2) decrease in amplitude, and 3) increase in spectral noise . A significant aspect of whispered speech is that variance in the F o is extremely restricted . The acoustic analysis of H .T . 's extemporaneous speaking revealed that while producing a vowel interruption, he changed the Fo of the duplicated vowel (mostly upward) during the production of the dysfluency . Perhaps the vowel interruption did not occur during whispered speech because the Fp of the vowel was greatly altered, that is, the stimulus required to trigger the vowel break may not have been present . Another plausible explanation for the elimination of vowel interruption dysfluencies during whispered speech is that the reduction of vocal fold



VOWEL INTERRUPTION

65

function when whispering reduced the physiological complexities of the speech task . The other speaking condition that resulted in elimination of vowel-interruption dysfluencies occurred during a re-reading of a passage in which words containing vowel interruptions in the initial reading had been eliminated . This phenomenon also has been observed among individuals who stutter (Johnson and Millsapps, 1937) . When reading a passage in which selected words produced with excessive laryngeal tension were eliminated, the stimuli that typically produced laryngeal tension is also eliminated and hence, the dystluency does not occur . This appears to be the case with individuals who stutter as well as with our subject . By creating a situation that reduces or eliminates the occasion for laryngeal tension, stuttering is reduced or eliminated or in our subject, vowel interruption is reduced or eliminated . The only other condition in which the vowel interruption was suppressed occurred when H .T . was asked not to break up the final word in a sentence . Although this was a difficult task for FIT ., he was able to eliminate the vowel interruption . This phenomena has been noted with individuals who stutter as well . When instructed to speak fluently many stutterers are able to do so for a short time period . It could be argued that the effort to speak differently could alter some key prosodic features that may trigger laryngeal tension . Atypical Prosodic Features An analysis of the prosodic features, speech rate, and rhythm patterns of H .T . 's speech revealed that these features differed from those found in adult speech . The reduced articulation rate, the uniform pause durations between utterances, the arrhythmic intersyllabic utterances patterns, and the lack of variability among syllable intensity peaks gives one the impression his speech lacks affect . The high Fo of his speaking voice and limited variance of F„ among individual words also contribute to the lack of affect in his speech . These differences may reflect the psychological disturbances noted in H .T .'s case history . While some prosodic features of .'sH speech resembled character.T istics of ataxic dysarthria and apraxia of speech (consistent F„ pattern within syllables, reduced articulation rate, and lack of variation in syllable intensity) reported by Kent and Rosenbek (1982), other features of ataxic dysarthria and apraxia of speech were not present . For example, at the time of testing, H .T . demonstrated adequate articulation skills, showed no signs of apraxia as measured by the screening test of apraxia, demonstrated adequate breath-stream management, could voluntarily correct dysfluencies, and demonstrated adequate control of speech movements .



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D . E . MOWRER and C . FAIRBANK

Individuals with motor-speech disorders usually experience difficulty in these areas (Darley, Aronson, and Brown, 1975) . Comparison with Neurogenic Stutterers Some similarities exist between certain features of UT's use of vowel interruptions and the dysfluencies that occur in the speech of stuttcrers who have been diagnosed as neurologically damaged . In a review of 14 studies of stuttcrers who had confirmed brain damage, Helm-Estabrooks ((986) reported that patients suffering from strokes, head trauma, or extrapyramidal disease, unlike developmental stuttcrers, evidence stuttering symptoms while singing, speaking rote paragraphs, speaking automated sequences, repeating words, and while tapping and speaking simultaneously . In addition, an adaptation effect rarely occurred, and most individuals were unable to "carry" a tune . Extraneous motor behaviors also rarely occurred in conjunction with the dysfluency . Although we observed similar features in the occurrence .T .'s of H dysfluencies, his dystluencies differed in that they never occurred on initial vowels, whereas dysfluencies of brain-damaged stuttcrers are reported to occur primarily with initial phonemes . Also, according to reports in the case history, the onset of H .T . 's dysiluent speech did not occur suddenly . We compared the occurrence of dysfluencies in H .T . 's speech with dysfluencies in the speech of a patient who, following a thoracic lamineetomy, involuntarily inserted the syllable [sis] in the final-word position (Van Lancker, Hogen, and Canter, 1983) . There was no similarity in the occurrence of the dysfluencies between the two subjects except that neither subject displayed anxiety associated with their dysfluencies . Canter (1971) identified seven characteristics that many patients who were diagnosed as neurogenic stutters (dysarthric, apraxie, and dipnomic stuttering) may have in common . Only three of the seven speech characteristics could apply to H .T .'s speech . Canter pointed out that few of his neurogenic stuttcrers share all seven characteristics . CONCLUSION Having analyzed this subject's verbal responses in a variety of speaking situations, it appears that excessive laryngeal tension occurs during production of stressed vowels . This tension results in various degrees of intravowel laryngealization, the greatest of which is realized as a glottal closure . It would he reasonable to expect, then, that by removing the stressed vowels, the stimuli required to evoke excessive laryngeal tension (and hence vowel interruption) would be eliminated . It is postulated that this is what occurred during whispering and when stressed vowels were eliminated from a speaking passage .



VOWEL INTERRUPTION

67

The important observation to be made here is that the vowel interruption decreased or disappeared when stressed vowels were withdrawn . Van Riper (1982) has suggested that dysfluencies in the speech of stutterers are reduced in many speaking conditions (singing, speaking in rhythm, choral reading, etc .) because a timing factor has been added to the speech signal . Van Riper goes on to suggest that stuttering may indeed be a disorder of speech timing . Perhaps it would be more insightful to consider what is withdrawn from the stimulus properties of the speaking condition rather than focusing on what might be added . Although our data do not warrant this observation, we would like to offer it as a possible research question for further study . We suggest that it may be possible that the stimulus that is withdrawn when the stutterer is asked to speak under controlled conditions of singing, choral speaking, during masking, and so on, is the speaker's auditory feedback that personally identifies him/her, that is, that individual me-ness" that some identify as one's self-concept as a speaker who has full communicative responsibility . We certainly are not the first to suggest the possible existence of such a stimulus property that might serve to trigger an emotional reaction in the speaker that leads to stuttering . It may be profitable to continue this search to identify the eliciting stimuli, for once identified the speech/language pathologist might be in a better position to help the stutterer learn to cope with these eliciting stimuli in a more effective manner . While it is not so difficult to explain what happens during H .T . 's vowel interruptions, attempts to explain why it occurs is yet another problem, perhaps an unsolvable one in this instance because of the lack of an adequate case history and the incomplete neurological evaluation . Nevertheless, it seems that the reasons why UT's dysfluencies occur are quite different from the reasons why stutterer's experience the broken word .

REFERENCES Adams, L .H . (1955) A comparison of certain sound wave characteristics of stutterer, and nonstutterers . In W . Johnson and R .R . Leutenegger (Eds .) . Stuttering in children and adults . Minneapolis : University of Minnesota Press . Brown, W .S ., Jr ., and Brands, J .F . (1971) Effects of auditory masking on vocal intensity and intraoral air pressure during sentence production . Journal of Acoustical Society of America, 49, 1903-1905 .

Canter, G . (1971) Observations of neurogenic stuttering : A contribution to differential diagnosis . British Journal of Disorders of Communication, 6, 139-143 . Critchley, M . (1970) Aphasiol ogy and other aspects oflanguage . London : Arnold . Darley, F ., Aronson, A ., and Brown J- (1975) Motor speech disorders . Philadelphia : W .B . Sanders Co .



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Deal, J .L . (1982) Sudden onset of stuttering : A case report . Journal of Speech & Hearing Disorders, 47, 301-304 . Erickson, R . (1969) Assessing communication attitudes among slutterers . Journal of Speech and Hearing Research, 12, 711-724 . Goldman-Eisler, F . (1968) Psycholinguistics Experiments in spontaneous speech . London : Academic Press . Helm-Estabrooks, N . (1986) Diagnosis and management of neurogenic stuttering in adults . In K .O . St . Louis (Ed .), The atypical stutterer: Principles and practices of rehabilitation (pp . 193-217) . Orlando . FL : Academic Press . Ingham, R . (1984) Stuttering anti behavior therapy . San Diego : College Hill . Johnson, W . (1961) Measurement of oral reading and speaking rate and dysfuency of adult male and female slutterers and nonstutterers . Journal of Speech and Hearing Disorders, Monograph Supplement No . 7 . . 1-20 . Johnson . W ., and Millsapps . L . S . (1937) Studies in the psychology of stuttering . V I . The role of cues representative of stuttering moments during oral reading . Journal of Speech Disorders, 2 . 101-104 . Johnson, W ., and Rosen, L . (1937) Studies in the psychology of stuttering : VII . Effect of certain changes in speech pattern upon fluency of stuttering . Journal of Speech Disorders, 2 . 105-109 . Kallail. K ., and Emanuel, F . (1984) An acoustic comparison of isolated whispered and phonated vowel samples produced by adult male subjects . Journal of Phonetics, 12 . 175-186 . Kent . R ., and Rosenbek, J . (1982) Prosodic disturbance and neurologic lesion . Brain and Language . I5, 259-291 . Miller, J ., Grosjean, F ., and Lomanlo . C . (1984) Articulation rate and its variability in spontaneous speech : Reanalyses and some implications . Phonetics . 41 . 215-225 . Parnell, M ., Amerman, J ., and Wells, G . (1977) Closure and constnsction duration for alveolar consonants during voiced and whispered speaking conditions . ./ournal of the Acoustical Society of America . 61, 612-613 . Pei . M ., and Gaynor, F . (1954) Dictionary of linguistics . New York : Philosophical Library . Perkins, W ., Rudas . J ., Johnson, L ., and Bell, J . (1976) Stuttering discoordination of phonation and articulation and respiration . Journal of Speech and Hearing Disorders, 19,509-522 . Ryan, B . (1974) Programmed therapy,far stuttering in children and adults . Springfield . IL : Charles C . Thomas . Starkweathcr . C .W . (1987) Fluency and stuttering . Englewood Cliffs, NJ : Prentice-Hall . Van Laneker, E ., Bogen, J ., and Canter, G . (1983) A case report of pathological rule-governed syllable intrusion . Brain and language, 20, 12-20 . Van Riper . C . (1982) The nature of stuttering . Englewood Cliffs, NJ : PrenticeHall .



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Ventry, LM ., and Schiavetti, N . 0980) Evaluating Research in Speech Pathology . Reading, MA : Addison-Wesley . Manuscript received December 1990, revised April 1991 : accepted May 1991 .