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Purpose: The current study investigated English prosodic focus marking by autistic and typically developing (TD) Cantonese trilingual children, and examined the potential differences in this regard compared to native English-speaking children. Method: Forty-eight participants were recruited with 16 speakers for each of the three groups (Cantonese-speaking autistic [CASD], Cantonese-speaking TD [CTD], and English-speaking TD [ETD] children), and prompt questions were designed to elicit desired focus type (i.e., broad, narrow, and contrastive focus). Mean duration, mean fundamental frequency (F0), F0 range, mean intensity, and F0 curves were used as the acoustic correlates for linear mixed-effects model fitting and functional data analyses in relation to groups and focus conditions (i.e., broad, narrow, and contrastive pre-, on-, and post-focus). Results: The CTD group had post-focus compression (PFC) patterns via reducing mean duration, narrowing F0 range, and lowering mean F0, F0 curve, and mean intensity for words under both narrow and contrastive post-focus conditions, while the CASD group only had shortened mean duration and lowered F0 curves. However, neither the CTD group nor CASD group showed much of onfocus expansion (OFE) patterns. The ETD group marked OFE by increasing mean duration, mean F0, mean intensity, and higher F0 curve for words under on-focus conditions. Conclusions: The CTD group utilized more acoustic cues than the CASD group when it comes to PFC. The ETD group differed from the CASD and CTD groups in the use of OFE. Furthermore, both the CASD and CTD groups showed positive first language transfer in the use of duration and intensity and, potentially, successful acquisition in the use of F0 for prosodic focus marking. Meanwhile, the differences in the use of OFE between the Cantonese-speaking and English-speaking groups, not PFC, might indicate that Cantonese-speaking children acquire PFC prior to OFE. [ABSTRACT FROM AUTHOR]

Purpose: The authors investigated lengthening effects in child-directed speech (CDS) across the sentence, testing the additive effects on duration of Word Position, Register, Focus, and Sentence Mode (statement/question). Method: Five theater students produced 6 sentences containing 5 monosyllabic words in a simulated dialogue, varying in Register, Focus, and Sentence Mode. The authors segmented a total of 1,800 sentences using forced-alignment tools, and they analyzed the duration of each word. Results: The results show significant effects of Register, Word Position, and their interactions. The simple effect of Register was significant in all 5 word positions, indicating a global elongation effect in CDS. Interestingly, there was no proportional increase of the final word in CDS. In addition, the 3-way interactions Register x Word Position x Focus and Register x Word Position x Sentence Mode were significant, which converge to the conclusion that the utterance-final word in CDS is additively elongated when it is focused and in a statement. Conclusion: Elongation in CDS is a global effect, but the additive effects of duration demonstrated in the authors' data suggest that the effect of enhanced utterance-final lengthening in CDS in naturalistic samples may be a by-product of discourse characteristics of CDS. [ABSTRACT FROM AUTHOR]

Purpose: The authors investigated lengthening effects in child-directed speech (CDS) across the sentence, testing the additive effects on duration of Word Position, Register, Focus, and Sentence Mode (statement/question). Method: Five theater students produced 6 sentences containing 5 monosyllabic words in a simulated dialogue, varying in Register, Focus, and Sentence Mode. The authors segmented a total of 1,800 sentences using forced-alignment tools, and they analyzed the duration of each word. Results: The results show significant effects of Register, Word Position, and their interactions. The simple effect of Register was significant in all 5 word positions, indicating a global elongation effect in CDS. Interestingly, there was no proportional increase of the final word in CDS. In addition, the 3-way interactions Register x Word Position x Focus and Register x Word Position x Sentence Mode were significant, which converge to the conclusion that the utterance-final word in CDS is additively elongated when it is focused and in a statement. Conclusion: Elongation in CDS is a global effect, but the additive effects of duration demonstrated in the authors' data suggest that the effect of enhanced utterance-final lengthening in CDS in naturalistic samples may be a by-product of discourse characteristics of CDS. [ABSTRACT FROM AUTHOR]

Purpose: A feedback perturbation paradigm was used to investigate whether prosodic cues are controlled independently or in an integrated fashion during sentence production. Method: Twenty-one healthy speakers of American English were asked to produce sentences with emphatic stress while receiving real-time auditory feedback of their productions. The fundamental frequency (F0) of the stressed word in each 4-word sentence was selectively shifted in a sensorimotor adaptation protocol. Speakers experienced either an upward or a downward shift of the stressed word, which gradually altered the perceived stress of the sentence. Results: Participants in the Up and Down groups adapted to F0 shifts by altering the contrast between stressed and unstressed words differentially, such that the two groups deviated from each other in the perturbation phase. Furthermore, selective FO perturbation in sentences with emphatic stress resulted in compensatory changes in both FO and intensity. Conclusions: Present findings suggest that FO and intensity are controlled in an integrated fashion to maintain the contrast between stressed and unstressed words. When a cue is impaired through perturbation, speakers not only oppose the perturbation but enhance other prosodic cues to achieve emphatic stress. [ABSTRACT FROM AUTHOR]

Purpose: The present study examined the effects of age and hearing status of a child on maternal use of pitch change, preboundary vowel lengthening, and pause duration, all of which are prosodic cues correlated with clause boundaries in infant-directed speech. Method: Mothers' speech to infants with normal hearing (NH; n = 18), infants who are profoundly deaf with a cochlear implant (HI; n = 9), and an adult experimenter were recorded at 2 time periods separated by 6 months. NH infants were matched to HI infants by chronological age or hearing experience. Fundamental frequency of pre- and postboundary vowels, vowel duration, and pause duration between utterances was measured. Results: Results demonstrated that mothers (a) exaggerated prosodic characteristics in infant-directed speech regardless of infants' hearing status; (b) tailored preboundary vowel lengthening to infants' hearing experience rather than to chronological age; and (c) decreased exaggeration of pause duration over time. Conclusions: The results suggest that acoustic cues correlated with clause boundaries are available in maternal speech to HI infants. Their exaggeration relative to adult-directed speech suggests that mothers' use of infant-directed speech is a natural behavior regardless of infant hearing status. Finally, mothers modify speech prosody according to their children's age and hearing experience. [ABSTRACT FROM AUTHOR]

Purpose: The present study examined the effects of age and hearing status of a child on maternal use of pitch change, preboundary vowel lengthening, and pause duration, all of which are prosodic cues correlated with clause boundaries in infant-directed speech. Method: Mothers' speech to infants with normal hearing (NH; n = 18), infants who are profoundly deaf with a cochlear implant (HI; n = 9), and an adult experimenter were recorded at 2 time periods separated by 6 months. NH infants were matched to HI infants by chronological age or hearing experience. Fundamental frequency of pre- and postboundary vowels, vowel duration, and pause duration between utterances was measured. Results: Results demonstrated that mothers (a) exaggerated prosodic characteristics in infant-directed speech regardless of infants' hearing status; (b) tailored preboundary vowel lengthening to infants' hearing experience rather than to chronological age; and (c) decreased exaggeration of pause duration over time. Conclusions: The results suggest that acoustic cues correlated with clause boundaries are available in maternal speech to HI infants. Their exaggeration relative to adult-directed speech suggests that mothers' use of infant-directed speech is a natural behavior regardless of infant hearing status. Finally, mothers modify speech prosody according to their children's age and hearing experience. [ABSTRACT FROM AUTHOR]

Purpose: Acquisition of prosodic control appears to evolve across development with younger children relying on durational cues and older children utilizing a broader spectrum of cues including fundamental frequency, intensity, and duration. This study aimed to determine whether unfamiliar listeners could identify prosodic contrasts produced by 4-, 7-, and 11-year-olds despite differences in acoustic cues used by each age group. Method: Thirty-six adult monolingual speakers of American English participated as listeners. A previous study yielded speech recordings from 12 children (2 male, 2 female from each age group) producing 2 linguistic contrasts, question-statement and contrastive stress, which served as listening stimuli. Results: In both tasks, listener accuracy ranged from 39.7% to 100% with significant differences between 4-year-olds and both older age groups. Listeners had difficulty deciphering the 4-year-olds' questions compared with statements and were more accurate in identifying contrastive stress placed on sentence-initial words compared with sentence-final words across all age groups. Conclusion: Although listeners identified prosodic contrasts produced by all 3 age groups, accuracy was significantly higher for 7- and 11-year-old productions. Findings are consistent with production studies that suggest relative stabilization of prosodic control between ages 4 and 7. Parallels between prosodic and segmental acquisition are discussed. [ABSTRACT FROM AUTHOR]

This investigation was motivated by observations that when persons with dysarthria increase loudness their speech improves. Some studies have indicated that this improvement may be related to an increase of prosodic variation. Studies have reported an increase of fundamental frequency (F0) variation with increased loudness, but there has been no examination of the relation of loudness manipulation to specific prosodic variables that are known to aid a listener in parsing out meaningful information. This study examined the relation of vocal loudness production to selected acoustic variables known to inform listeners of phrase and sentence boundaries: specifically, F0 declination and final-word lengthening. Ten young, healthy women were audio-recorded while they read aloud a paragraph at what each considered normal loudness, twice-normal loudness, and half-normal loudness. Results showed that there was a statistically significant increase of F0 declination, brought about by a higher resetting of F0 at the beginning of a sentence and an increase of final-word lengthening from the half-normal loudness condition to the twice-normal loudness condition. These results suggest that when some persons with dysarthria increase loudness, variables related to prosody may change, which in turn contributes to improvement in communicative effectiveness. However, until this procedure is tested with individuals who have dysarthria, it is uncertain whether a similar effect would be observed. [ABSTRACT FROM AUTHOR]

This investigation was motivated by observations that when persons with dysarthria increase loudness their speech improves. Some studies have indicated that this improvement may be related to an increase of prosodic variation. Studies have reported an increase of fundamental frequency (F0) variation with increased loudness, but there has been no examination of the relation of loudness manipulation to specific prosodic variables that are known to aid a listener in parsing out meaningful information. This study examined the relation of vocal loudness production to selected acoustic variables known to inform listeners of phrase and sentence boundaries: specifically, F0 declination and final-word lengthening. Ten young, healthy women were audio-recorded while they read aloud a paragraph at what each considered normal loudness, twice-normal loudness, and half-normal loudness. Results showed that there was a statistically significant increase of F0 declination, brought about by a higher resetting of F0 at the beginning of a sentence and an increase of final-word lengthening from the half-normal loudness condition to the twice-normal loudness condition. These results suggest that when some persons with dysarthria increase loudness, variables related to prosody may change, which in turn contributes to improvement in communicative effectiveness. However, until this procedure is tested with individuals who have dysarthria, it is uncertain whether a similar effect would be observed. [ABSTRACT FROM AUTHOR]

Studies of prosodic control in severe dysarthria (DYS) have focused on differences between impaired and nonimpaired speech in terms of the range and variation of fundamental frequency (F0), intensity, and duration. Whether individuals with severe DYS can adequately signal prosodic contrasts and which acoustic cues they use to do so has received far less attention. This article focused on the question-statement contrast. In nonimpaired speech, this contrast is believed to be cued primarily by FO, although some researchers have argued that duration also plays a role. This study examined how 8 speakers with severe DYS due to cerebral palsy signaled the question-statement contrast for a set of 10 short phrases. An additional 8 healthy controls (HCs) produced the same set of phrases as questions and statements. To analyze the speech recordings, peak FO (F0peak), average FO (F0ave), slope of FO (F0slope), peak intensity (INTpeak), average intensity (INTave), slope of intensity (INTslope), and duration measures were calculated for each syllable (S1, S2, S3) within each phrase. Acoustic analyses revealed that speakers with DYS and HCs used FO, duration, and to a lesser degree, intensity cues to signal the contrast. Moreover, productions by speakers with DYS had longer and louder S3 for questions compared to productions by HCs, suggesting that speakers with DYS may have been compensating for their reduced ability to control FO by exploiting their residual control of loudness and duration. Data from a previous perceptual study (R. Patel, 2002b) with the same speakers with DYS were used to analyze the relationship between acoustic characteristics and listener perceptions of their productions. Logistic regression analysis revealed that S1_F0ave; S2_duration; and S3_duration, S3_F0peak, S3_F0slope, S3_InTave, and S3_Intslope were... [ABSTRACT FROM AUTHOR]

Speakers with severe dysarthria are known to have reduced range in prosody. Consistent control within that range, however, has largely been ignored. In earlier investigations speakers with severe dysarthria were able to control pitch and duration for sustained vowel production despite reduced flexibility of control (Patel, 1998). The present experiment examined whether 8 speakers with severe dysarthria due to cerebral palsy used prosodic parameters of pitch contour and syllable duration for phrase-level productions. Speakers with dysarthria (N = 8) produced 3-syllable phrases as questions and statements. Naïve listeners (N = 48) classifed dysarthric productions as either questions or statements. Listeners were able to distinguish questions from statements with accuracy levels ranging from 81% to 98 %. We were also interested in studying how dysarthric speakers marked the question-statement contrast. Prosodic features of pitch contour and syllable duration were systematically removed from the original recorded vocalizations to examine the salience of these features on listener classification. Removal of pitch contour cues dramatically reduced listener accuracy scores to almost chance performance. Listeners found pitch contour cues to be information-bearing cues in dysarthric vocalizations even though the range of frequency control in these speakers may be reduced. That speakers with dysarthria were able to exert sufficient control to signal the question-statement contrast has implications for diagnostic and intervention practices aimed to optimally exploit prosodic control for enhancing communication efficiency. [ABSTRACT FROM AUTHOR]

Two tests of the ability of individuals with left-hemisphere damage (LHD) and right-hemisphere damage (RHD) and non-brain-damaged participants to identify phonemic and emphatic stress contrasts were undertaken. From a set of naturally produced base stimuli, two additional stimulus sets were derived. In one, fundamental frequency (F0) cues to stress were neutralized, whereas in the other duration cues were effectively neutralized. Results demonstrated that individuals with LHD were unable to identify phonemic stress contrasts with better-than-chance accuracy; individuals with RHD performed worse than normal participants but significantly better than the patients with LHD-particularly with the original full-cue stimuli. All groups performed better on the emphatic stress subtest, with the scores of only the patients with LHD at chance level for the F0-neutralized stimuli. The findings are considered in relation to hypotheses concerning the hemispheric lateralization of prosodic processing, particularly with respect to a hypothesis that posits differential lateralization for specific acoustic parameters. [ABSTRACT FROM AUTHOR]

Analyzes tests on the ability of individuals with left-hemisphere damage (LHD), right-hemisphere damage and non-brain damaged participants to identify phonemic and emphatic stress contrasts. Impairment of the ability of patients with LHD and aphasia to make phonemic stress judgments; Interaction of perceptual deficits and higher level linguistic and/or cognitive deficits.