Sentence Duration Research Articles

Shifting perceptions of age in voice

A series of experiments have been carried out in order to identify the acoustical and perceptual correlates of the aging voice. The initial phase of the program was to identify those voice parameters which signal a person’s age; the second phase was to systematically shift these parameters in order to determine if a parallel change in perceived age would occur. This second study focused on temporal characteristics related to voice. In this instance, standard speech samples for 16 males aged 70–90 years were contrasted with those of 14 males aged 20–33 years. The features studied included the following: (1) sentence duration, (2) word duration, (3) diphthong duration, (4) consonant-vowel ratios, (5) number of pauses and (6) pause duration. Significant differences were found for all relationships. Subsequently, a preliminary study was carried out where the voices were synthesized and the temporal parameters for the two groups shifted toward each other. The preliminary data suggest that such modifications lead especially to the idea that the voices of older individuals actually were those of younger men.

Caractéristiques vocaliques intrinsèques et co-intrinsèques dans les dysarthries cérébelleuse et parkinsonienne

Les caractéristiques intrinsèques et co-intrinsèques des voyelles ont été peu étudiées dans les dysarthries neurologiques. Cette étude évalue ces paramètres, en confrontant à une population de 10 sujets témoins 4 sujets dysarthriques cérébelleux atteints d’un syndrome cérébelleux dégénératif et 4 sujets dysarthriques parkinsoniens atteints de la maladie de Parkinson. Une rééducation intensive de la parole de type Lee Silverman (LSVT) a par ailleurs été appliquée à un sujet parkinsonien appartenant à la population étudiée, avec une évaluation avant et après rééducation. Les mesures acoustiques appréciaient la durée et la fréquence des voyelles [a, i, u] au sein de contextes consonantiques variés, leurs valeurs formantiques ainsi que la durée des phrases. Les résultats montrent des altérations différentes selon le type de dysarthrie, ainsi que des formes de transposition de contrastes. La rééducation du sujet dysarthrique parkinsonien a pour effet de restaurer des contrastes sub-normaux.

Speech timing and working memory in profoundly deaf children after cochlear implantation

Thirty-seven profoundly deaf children between 8- and 9-years-old with cochlear implants and a comparison group of normal-hearing children were studied to measure speaking rates, digit spans, and speech timing during digit span recall. The deaf children displayed longer sentence durations and pauses during recall and shorter digit spans compared to the normal-hearing children. Articulation rates, measured from sentence durations, were strongly correlated with immediate memory span in both normal-hearing and deaf children, indicating that both slower subvocal rehearsal and scanning processes may be factors that contribute to the deaf children’s shorter digit spans. These findings demonstrate that subvocal verbal rehearsal speed and memory scanning processes are not only dependent on chronological age as suggested in earlier research by Cowan and colleagues (1998). Instead, in this clinical population the absence of early auditory experience and phonological processing activities before implantation appears to produce measurable effects on the working memory processes that rely on verbal rehearsal and serial scanning of phonological information in short-term memory.

Sentence durations and accentedness judgments

Talkers in a second language can frequently be identified as speaking with a foreign accent. It is not clear to what degree a foreign accent represents specific deviations from a target language versus more general characteristics. We examined the identifications of native and non-native talkers by listeners with various amount of knowledge of the target language. Native and non-native speakers of Latvian provided materials. All the non-native talkers spoke Russian as their first language and were long-term residents of Latvia. A listening test, containing sentences excerpted from a short recorded passage, was presented to three groups of listeners: native speakers of Latvian, Russians for whom Latvian was a second language, and Americans with no knowledge of either of the two languages. The listeners were asked to judge whether each utterance was produced by a native or non-native talker. The Latvians identified the non-native talkers very accurately, 88%. The Russians were somewhat less accurate, 83%. The American listeners were least accurate, but still identified the non-native talkers at above chance levels, 62%. Sentence durations correlated with the judgments provided by the American listeners but not with the judgments provided by native or L2 listeners.

Factors associated with development of speech production skills in children implanted by age five.

This study investigated speech production outcomes and the factors influencing the outcomes in children who had 4 to 6 yr of experience with a multichannel cochlear implant. Production variables examined included speech intelligibility, accuracy of consonant and vowel production, percentage of plosives and fricatives produced, duration of sentences, percentage of time involved in communication breakdowns during a communication sample, and responses to a speech usage questionnaire. 181 children between the ages of 8 and 9 yr who received a multichannel cochlear implant before age 5 yr participated as subjects. Independent variables were the amount and type of educational intervention and intervening variables were distributed across child, family and implant characteristics. Multiple regression analyses provided a measure of the amount of variance associated with speech production skills accounted for by the intervening and independent variables. Performance for the key words in the speech intelligibility measured averaged 63.5% for the group of children. Accuracy of phoneme production was higher for consonants (68.0%) than for vowels (61.6%) for the group. More plosives were present for acoustic analyses (91.6%) than were fricatives (78.4%). Duration for the speech intelligibility sentences averaged 2572.3 msec. Communication breakdowns occurred on average 14.5% of the time involved in a language sample. Significant predictors of high levels of oral communication skills included higher nonverbal intelligence, gender, longer use of SPEAK processing strategy, a fully active electrode array, greater dynamic range, and greater growth of loudness. The primary rehabilitative factors contributing to high levels of oral communication were an emphasis on oral-aural communication and classrooms that emphasized dependence on speech and listening. Speech production performance in children with cochlear implants is influenced by nonverbal intelligence, gender, implant characteristics including the length of time using the newest speech processing strategies, and educational programs emphasizing oral-aural communication. Factors previously thought to be major contributors to speech production performance, such as age of onset of deafness and age of implantation, did not appear to play significant roles in predicting levels of speech production performance.

Characteristics of Fricatives and Sentence Duration after Cochlear Implantation

Ten postlingually deafened patients (5 male, 5 female) were examined after cochlear implantation to measure improvements in their quality of speech. Parameters such as the spectral maximum of fricatives and the duration of utterances were analysed in speech recordings taken at regular intervals after implantation. The speech samples were recorded in an audiological chamber. Parameters were analysed using ST^x (S-Tools Software). Frequency analyses based on the fast Fourier transform and spectral estimation methods, as well as fundamental frequency and formant extraction (cepstrum, LPC = linear prediction coding) and digital filter implementations were prepared. The results indicate a tendency towards improvement in the spectral maximum of the fricatives and affricates and a shortening of the duration of the fricative parts in affricates and of sentences in nearly all our subjects. These results showed the restored auditory feedback produced by cochlear implantation to have a favourable effect on speech production.

Acoustic Characteristics of the Speech of Young Cochlear Implant Users: A Comparison with Normal-Hearing Age-Mates

The primary objective of this study was to compare select acoustic characteristics of the speech of deaf children who use cochlear implants (young cochlear implant users) with those of children with normal hearing. A secondary objective of this study was to examine the effect, if any, of the deaf child's education (oral versus total communication) on the similarity of these acoustic characteristics to those of normal-hearing age-mates. Speech was recorded from 181 young cochlear implant users and from 24 children with normal hearing. All speech was produced by imitation, and consisted of complete sentences. Acoustic measures included voice onset time (/t/, /d/), second formant frequency (/i/, /[U0254]/), spectral moments (mean, skew and kurtosis of /s/ and /[U0283]/), a nasal manner metric, and durations (of vowels, words, and sentences). A large percentage (46 to 97%) of the young cochlear implant users produced acoustic characteristics with values within the range found for children with normal hearing. Exceptions were sentence duration and vowel duration in sentence-initial words, for which only 23 and 25%, respectively, of the COCHLEAR IMPLANT users had values within the normal range. Additionally, for most of the acoustic measures, significantly more COCHLEAR IMPLANT users from oral than from total communication settings had values within the normal range. Compared with deaf children with hearing aids (from previous studies by others), deaf children who use cochlear implants have improved speech production skills, as reflected in the acoustic measures of this study. Placement in an oral communication educational setting is also associated with more speech production improvement than placement in a total communication setting.

Assessing bilingual dominance

This study used two methods to assess bilingual dominance in four groups of 18 Italian–English bilinguals, who were selected on the basis of age of arrival (AOA) in Canada (early: 2–13 years; late: 15–26 years) and percentage use of the first language (L1), Italian (low L1 use: 1–15%; high L1 use: 25–85%). Ratios were derived from the bilinguals' self-ratings of ability to speak and understand Italian compared to English (the “verbal” self-rating ratios) and to read and write Italian compared to English (the “written” self-rating ratios). The ratio of the mean duration of English and Italian sentences produced by each bilingual was also computed. AOA and L1 use had the same effect on the self-rating and sentence duration ratios, which were correlated. The bilinguals who arrived in Canada as young adults and continued to use Italian often were the most likely to be Italian dominant. Dominance in Italian was associated with a relatively high level of performance in Italian (assessed in a translation task) and relatively poor performance in English (assessed by measuring strength of foreign accents). Both groups of late bilinguals (late low, late high) and both groups of early bilinguals (early low, early high) were found to produce English sentences with detectable accents. However, a group of 18 bilinguals (all early bilinguals) selected from the original sample of 72 based on their dominance in English did not have detectable foreign accents. This suggested that interlingual interference effects may not be inevitable.

Factors affecting the duration of native and second-language sentences produced in unspeeded and speeded conditions

The aim of this study was to provide insight into why non-natives generally produce longer second-language (L2) sentences than native speakers do. Four groups of 16 Italian–English bilinguals were recruited in Ottawa based on orthogonal differences in age of arrival (AOA) to Canada from Italy (early versus late) and self-reported percentage Italian use (low-L1 use versus high-L1 use). The bilinguals repeated duration-matched English and Italian sentences presented via a loudspeaker in an ‘‘unspeeded’’ condition, then as rapidly as possible (the ‘‘speeded’’ condition). The same effect of AOA was obtained in both conditions despite a 20% reduction in sentence duration in the speeded condition. That is, the early bilinguals produced significantly shorter English than Italian sentences, whereas the late bilinguals produced significantly longer English than Italian sentences. Different L1 use effects were obtained in the two conditions, however. In the unspeeded condition, the low-L1-use bilinguals produced shorter English than Italian sentences, with a nonsignificant effect of language for high-L1-use bilinguals. In the speeded condition, high-L1-use bilinguals produced shorter Italian than English sentences, with no language effect for the low-L1-use bilinguals. The underlying bases of AOA and L1 use effects on L2 sentence production will be discussed. [Work supported by NIH.]

Preservation of second formant transitions during simultaneous communication:: A locus equation perspective

This study investigated the preservation of second formant transition acoustic cues to intelligibility in speech produced during simultaneous communication (SC) from a locus equation perspective. Twelve normal hearing, experienced sign language users were recorded under SC and speech alone (SA) conditions speaking a set of sentences containing monosyllabic words designed for measurement of second formant frequencies in consonant–vowel–consonant (CVC) syllables. Linear regression fits made to coordinates representing second formant transition onset and offset frequencies following stop consonant release of CVC syllables (locus equations) were used to examine place of articulation cues in both SA and SC conditions. Although results indicated longer sentence durations for SC than SA, locus equation slopes and intercepts obtained from speech produced during SC were virtually identical to those obtained during SA, indicating no degradation of stop consonant acoustic cues during SC. This conclusion is consistent with previous research indicating that temporal alterations produced by SC do not involve violations of other rules of spoken English. Educational objectives: As a result of this activity, the participant will be able to (1) describe SC; (2) explain the role of SC in communication with children who are deaf; (3) describe second formant transitions in English speech; and (4) identify second formant transition patterns in speech produced during SC.

Acoustic Measures of Symptoms in Abductor Spasmodic Dysphonia

Speech of patients with abductor spasmodic dysphonia (ABSD) was analyzed using acoustic analyses to determine: (1) which acoustic measures differed from controls and were independent factors representing patients' voice control difficulties, and (2) whether acoustic measures related to blinded perceptual counts of the symptom frequency in the same patients. Patients' voice onset time for voiceless consonants in speech were significantly longer than the controls ( p = 0.015). A principle components analysis identified three factors that accounted for 95% of the variance: the first factor included sentence and word duration, frequency shifts, and aperiodic instances; the second was phonatory breaks; and the third was voice onset time. Significant relationships with perceptual counts of symptoms were found for the measures of acoustic disruptions in sentences and sentence duration. Finally, a multiple regression demonstrated that the acoustic measures related well with the perceptual counts ( r 2 = 0.84) with word duration most highly related and none of the other measures contributing once the effect of word duration was partialed out. The results indicate that some of the voice motor control deficits, namely aperiodicity, phonatory breaks, and frequency shifts, which occur in patients with ABSD, are similar to those previously found in adductor spasmodic dysphonia. Results also indicate that acoustic measures of intermittent disruptions in speech, voice onset time, and speech duration are closely related to the perception of symptom frequency in the disorder.

Recidivism Among Serious Violent Crime Offenders in Finland

Abstract The recidivism of violent crimes among released offenders is an important issue, which must be taken into account when both the appropriate length of a prison sentence and release on parole are considered. We studied recidivism among high-risk violent offenders during their incarceration, parole, and freedom. The sample consisted of 99 Finnish men who were evaluated by a special prison court between July 1, 1971, and December 31, 1995. Forty-two of the men were sentenced to the special security section by the prison court (PDDR) and served their entire sentence. The remaining 57 convicts served their terms among the normal prison population (NPS) and were released on parole after having served, on average, 75% of their sentence (duration of parole was the remaining 25% of the original sentence). During parole, the probability of committing a serious violent offence among habitually violent male offenders was extremely high: 214-fold (Risk Ratio 214, 95% Confidence Interval 152-302) when compared ...

Effect of Bilateral Stimulation of the Subthalamic Nucleus on Parkinsonian Voice

The purpose of this study was to assess several acoustic features of the voices of 26 parkinsonian patients under two conditions, with and without bilateral chronic stimulation of the subthalamic nucleus (STN) to estimate the effectiveness of this procedure on parkinsonian speech. When compared to unstimulated patients, stimulated patients showed longer duration of sustained vowels, shorter duration of sentences, nonsense words, and pauses, more variable fundamental frequency (f0) in sentences, and more stable f0 during sustained vowels. Relative intensity was unchanged in both conditions. Further acoustic analyses are warranted to clarify the role of STN stimulation on parkinsonian speech.

Eliciting reduced, citation, and hyperarticulated speech in the laboratory: Acoustic and perceptual analyses

A method was developed to elicit sentences in three speech styles (reduced, citation, hyperarticulated) using controlled materials. The reduced style was elicited by having subjects read sentences while, as a distractor task, recalling a digit sequence from short-term memory. In prior work, the digit sequence length was calibrated to the individual subject’s digit span. Using this procedure, a reduced style was elicited from half of the subjects. In this study, the sequence length was set to one additional digit beyond the individual subject’s digit span, in the hope that the more difficult distractor task would consistently elicit a reduced style. The citation style was elicited by having subjects read sentences from a list. The hyperarticulated style was elicited by prompting subjects to reread some sentences again more carefully. Ten subjects were recorded in this experiment. The resulting sentences were acoustically analyzed in terms of sentence duration, keyword duration, and vowel space size. Sentences differing only in style were also presented in a paired comparison test to 35 listeners. The results of both the acoustic analysis and the perception test showed the method was successful in consistently eliciting reduced sentences from 8 subjects, and citation and hyperarticulated sentences from all 10 subjects.

Acoustic Analyses of Trained Singers Perceptually Identified from Speaking Samples

This study investigated selected acoustic cues in the speaking voices of five professional singers; cues that may have enabled naïve listeners to differentiate them from nonsingers and other trained singers who were not consistently identified from their speaking voices. Subjects were divided into three groups based on listeners' perceptual judgments. Group I, the identified singers, consisted of five professional singers, three males and two females, with an average identification score, from their speaking utterances, of 79%. Group II, the unidentified singers, consisted of 15 trained singers, seven males and eight females, who, as a group, were identified correctly from their speaking utterances only 52% of the time. Group III consisted of 20 nonsingers who were incorrectly identified from their speaking utterances as singers only 36% of the time, that is, they were correctly identified as nonsingers from their speech 64% of the time. Acoustic parameters chosen for measurement from vowel productions were: (1) percent jitter, (2) percent shimmer, and (3) noise-to-harmonic ratio. The second sentence of the “Rainbow Passage” was selected to compare several frequency and duration measures between the three groups. These were: (1) mean speaking fundamental frequency, (2) standard deviation of the fundamental frequency, (3) sentence duration, (4) word duration, and (5) consonant/vowel ratio. The data indicated that the acoustic parameters that most consistently distinguished the identified singers from the unidentified singers and the nonsingers were fundamental frequency variation and durational differences. The identified singers varied their speaking fundamental frequency significantly more than did both the unidentified singers and the nonsingers. The identified singers also had longer vocalic segments than did the others.

Recognition of time-distorted sentences by normal-hearing and cochlear-implant listeners.

This study evaluated the effects of time compression and expansion on sentence recognition by normal-hearing (NH) listeners and cochlear-implant (CI) recipients of the Nucleus-22 device. Sentence recognition was measured in five CI users using custom 4-channel continuous interleaved sampler (CIS) processors and five NH listeners using either 4-channel or 32-channel noise-band processors. For NH listeners, recognition was largely unaffected by time expansion, regardless of spectral resolution. However, recognition of time-compressed speech varied significantly with spectral resolution. When fine spectral resolution (32 channels) was available, speech recognition was unaffected even when the duration of sentences was shortened to 40% of their original length (equivalent to a mean duration of 40 ms/phoneme). However, a mean duration of 60 ms/phoneme was required to achieve the same level of recognition when only coarse spectral resolution (4 channels) was available. Recognition patterns were highly variable across CI listeners. The best CI listener performed as well as NH subjects listening to corresponding spectral conditions; however, three out of five CI listeners performed significantly poorer in recognizing time-compressed speech. Further investigation revealed that these three poorer-performing CI users also had more difficulty with simple temporal gap-detection tasks. The results indicate that limited spectral resolution reduces the ability to recognize time-compressed speech. Some CI listeners have more difficulty with time-compressed speech, as produced by rapid speakers, because of reduced spectral resolution and deficits in auditory temporal processing.

Sentence intonation and syllable stress in speech produced during simultaneous communication

This study investigated prosodic variables of syllable stress and intonation contours in speech produced during simultaneous communication. Simultaneous communication (SC) refers to speech combined with manually coded English (sign and finger spelling) for the production of each word of an utterance and is used in communication between hearing and deaf persons. 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 spoken English.

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.

Age of learning effects on the duration of sentences produced in a second language

Research has shown that L2 utterances diverge increasingly from target language phonetic norms as the age of L2 learning increases. Other research has suggested that L2 speakers produce longer utterances than native speakers. The aim of this study was to determine whether L2 utterance durations increase as age of learning increases. Fluently produced English sentences spoken by 240 native speakers of both Italian and Korean (selected on the basis of age of arrival [AOA]) were examined. For both L1 groups, the duration of English sentences was positively correlated with AOA. The AOA effect was found to be significant even when confounding variables were partialed out. These results are taken as preliminary support for the proposal that the more established the L1 is at the time of first exposure to the L2, the more it will interfere with L2 production, thus requiring greater processing resources to suppress it.

The effect of partially restored hearing on speech production of postlingually deafened adults with multichannel cochlear implants.

The effect of auditory feedback on speech production was investigated in five postlingually deafened adults implanted with the 22-channel Nucleus device. Changes in speech production were measured before implant and 1, 6, and 24 months postimplant. Acoustic measurements included: F1 and F2 of vowels in word-in-isolation and word-in-sentence context, voice-onset-time (VOT), spectral range of sibilants, fundamental frequency (F0) of word-in-isolation and word-in-sentence context, and word and sentence duration. Perceptual ratings of speech quality were done by ten listeners. The significant changes after cochlear implantation included: a decrease of F0, word and sentence duration, and F1 values, and an increase of voiced plosives' voicing lead (from positive to negative VOT values) and fricatives' spectral range. Significant changes occurred until 2 years postimplant when most measured values fell within Hebrew norms. Listeners were found to be sensitive to the acoustic changes in the speech from preimplant to 1, 6, and 24 months postimplant. Results suggest that when hearing is restored in postlingually deafened adults, calibration of speech is not immediate and occurs over time depending on the age-at-onset of deafness, years of deafness, and perception skills. The results also concur with hypothesis that the observed changes of some speech parameters are an indirect consequence of intentional changes in other articulatory parameters.