Journal of Speech Language and Hearing Research最新文献

Purpose: The current study addresses a gap in the literature regarding syntactic development of adolescent boys with fragile X syndrome (FXS) and Down syndrome (DS). Specifically, we ask whether syntactic skills plateau or continue to change during adolescence for these groups and whether the profile of syntactic change differs between boys with FXS and those with DS.

Method: Participants were 38 boys with FXS (with and without autism) and 20 boys with DS between the ages of 10 and 16 years, as well as 33 boys who were neurotypical between the ages of 3 and 8 years at study entry. Trained examiners evaluated the participants annually for four consecutive years. The evaluation included standardized language assessments and a conversational language sample, which was analyzed using mean length of utterance-morphemes and the Index of Productive Syntax. For each measure, we fit a series of candidate models, including the intercept-only model and models with nonverbal cognition and maternal IQ as moderators. We then used Akaike's information criteria-corrected to determine which model in a candidate set had the most empirical evidence.

Results: Our between-groups results indicated that FXS and DS have distinct syntactic profiles. However, our growth analyses and moderator analyses yielded mixed results. For most measures, the most likely models suggest that there is no plateau in the growth of syntactic skills for boys with FXS or DS and that nonverbal cognition is associated with the rate of change.

Conclusions: These results suggest that syntactic change continues to occur throughout adolescence for boys with FXS or DS. The results also indicate that the growth profiles are distinct between the two groups. Future research with more participants from more diverse backgrounds would add more clarity to these findings.

Supplemental material: https://doi.org/10.23641/asha.27984548.

Purpose: In the context of a cocktail party listening environment, the processing of different linguistic hierarchy levels in unattended speech and their influence on target speech recognition remain controversial. This study aims to investigate how different levels of linguistic structures (such as syllable, word, and sentence) in competing speech influence the recognition of target speech in a speech-to-speech masking situation.

Method: Thirty-six participants were instructed to recognize target speech when it was masked by competing speech varied in masking types across syllables, words, and sentence. The perceived spatial location was altered to examine the interaction between linguistic unmasking effects and spatial unmasking effects. Recognition performance (i.e., intelligibility threshold) was determined by fitting psychometric functions to the recognition accuracies across four signal-to-noise ratios (-14, -10, -6, and - 2 dB) to evaluate each subject's ability to cope with challenging listening conditions.

Results: We revealed a significant decline in target speech recognition when the masking speech was linguistically structured and intelligible. Specifically, masking speech with higher linguistic complexity, such as coherent sentences, resulted in more significant interference compared to those with lower complexity, like sequences of syllables. The linguistic release from masking, resulting from a decrease in linguistic complexity of maskers shifting from sentences to syllables, was found to be correlated with, and also linearly additive to, the spatial release from masking due to the spatial separation of the masker and target.

Conclusions: These findings illustrate the influence of linguistic complexity in masking speech on the recognition of target speech, suggesting the involvement of higher-level linguistic processing of irrelevant speech in noisy environment.

Purpose: Earlier work has established developmental benchmarks for intelligibility and articulation rate, but the intersection of these two variables, especially within individual children, has received limited attention. This study examines the interaction between intelligibility and speaking rate in typically developing children between the ages 2;6 and 9;11 (years;months) and evaluates whether children show a speed-accuracy trade-off in their habitual speech production.

Method: Speech samples of varying lengths were collected from 538 typically developing children. Intelligibility was measured as the number of words correctly transcribed by untrained adult listeners, and speaking rate was calculated in number of syllables per second. Regression models estimated the effects of age, utterance length, and speaking rate on intelligibility.

Results: Intelligibility and speaking rate were positively correlated overall but weakly correlated after adjusting for age. In regression analyses, intelligibility increased with age and decreased with utterance length, and there was a trend for intelligibility to decrease with increased speaking rate, especially in longer utterances. At the individual level, for most children, there was a negative effect of speaking rate on intelligibility.

Conclusions: Our findings provide evidence from a large-scale sample for the hypothesis that children's speech is subject to a speed-accuracy trade-off where increased speaking rate leads to reduced articulatory accuracy and hence reduced intelligibility. Further research is needed on how to apply this trade-off in a clinical setting.

Supplemental material: https://doi.org/10.23641/asha.27964125.

Purpose: When using the spatiotemporal index (STI) to measure variability across repetitions of the same stimulus, researchers will typically screen and remove productions that contain errors or disfluencies. However, this screening process is highly subjective, reduces the amount of data available, and may generate samples that are less representative of true speech difficulties. In this study, we quantify the degree to which the STI is skewed by the inclusion of highly deviating productions and whether alternative calculations could better facilitate their inclusion.

Method: First, we conducted a controlled simulation to quantify how highly deviating productions skew STI values. The traditional STI calculation was compared to three robust alternative measures proposed to reduce the influence of outlying productions. Next, using audio recordings from typically developing (TD) children and children with childhood apraxia of speech (CAS), we investigated how effectively each STI measure differentiated the two groups.

Results: Simulation findings demonstrated that the STI can be heavily skewed (more than doubling in value) by the inclusion of a single outlying production. In contrast, the robust alternative measures were all able to incorporate multiple outlying productions before their value was significantly altered. The proposed best-5 STI measure produced larger group differences between TD children and children with CAS compared to the traditional STI in both "Mom pets the puppy" and "Buy Bobby a puppy" stimuli.

Conclusions: The STI is highly sensitive to outlying productions and requires careful consideration of the repetitions included in its calculation. However, conservative approaches to data removal may be problematic when studying populations that are prone to fluency errors. In these scenarios, more robust alternatives to the STI, such as the best-5 STI measure, may provide a more practical approach to measuring speech variability.

Supplemental material: https://doi.org/10.23641/asha.27973236.

Purpose: Research has found an advantage to maintaining an external attentional focus while speaking as an increase in accuracy and a decrease in across-sentence variability has been found when producing oral-motor and speech tasks. What is not clear is how attention affects articulatory variability both across and within sentences, or how attention affects articulatory control in speakers who stutter. The purpose of this study was to investigate the effects of an internal versus external attention focus on articulatory variability at the sentence level.

Method: This study used linear (spatial-temporal index [STI]) and nonlinear (recurrence quantification analysis [RQA]) indices to measure lip aperture variability in 10 adults who stutter (AWS) and 15 adults who do not stutter (ANS) while they repeated sentences under an internal versus external attentional focus, virtual reality task (withVR.app; retrieved December 2023 from https://therapy.withvr.app). Four RQA measures were used to calculate within sentence variability including percent recurrence, percent determinism (%DET), stability (MAXLINE), and stationarity (TREND). Sentence duration measures were also obtained.

Results: AWS' movement durations were significantly longer than those of the ANS across conditions, and the AWS were more affected by the attentional focus shifts as their speech rate significantly increased when speaking with an external focus. AWS' speech patterns were also significantly more deterministic (%DET) and stable (MAXLINE) across attentional focus conditions compared to those of the ANS. Both groups showed an effect from attentional shifts as they exhibited less variability (i.e., more consistent) across sentences (STI) and less determinism (%DET) and stability (MAXLINE) within sentences when repeating sentences under an external attentional focus. STI values were not significantly different between the AWS and ANS for the internal or external attentional focus tasks. There were no significant main effects for group or condition for TREND; however, a main effect for sentence type was found.

Conclusion: Results suggest that AWS use a more restrictive and less flexible approach to movement and that an external focus fosters more flexibility and thus responsiveness to external factors.

Purpose: Prior research introduced quantifiable effects of three methodological parameters (number of repetitions, stimulus length, and parsing error) on the spatiotemporal index (STI) using simulated data. Critically, these parameters often vary across studies. In this study, we validate these effects, which were previously only demonstrated via simulation, using children's speech data.

Method: Kinematic data were collected from 30 typically developing children and 15 children with developmental language disorder, all spanning the ages of 6-8 years. All children repeated the sentence "buy Bobby a puppy" multiple times. Using these data, experiments were designed to mirror the previous simulated experiments as closely as possible to assess the effects of analytic decisions on the STI. Experiment 1 manipulated number of repetitions, Experiment 2 manipulated stimulus length (or the number of movement units in the target phrase), and Experiment 3 manipulated precision of parsing of the articulatory trajectories.

Results: The findings of all three experiments closely mirror those of the prior simulation. Experiment 1 showed consistent underestimation of STI values from smaller repetition counts consistent with the theoretical model for all three participant groups. Experiment 2 found speech segments containing fewer movements yield lower STI values than longer ones. Finally, Experiment 3 showed even small parsing errors are found to significantly increase measured STI values.

Conclusions: The results of this study are consistent with the findings of prior simulations in showing that the number of repetitions, length of stimuli, and amount of parsing error can all strongly influence the STI independent of behavioral factors. These results further confirm the importance of closely considering the design of experiments, which employ the STI.

Purpose: This study examined the race identification of Southern American English speakers from two geographically distant regions in North Carolina. The purpose of this work is to explore how talkers' self-identified race, talker dialect region, and acoustic speech variables contribute to listener categorization of talker races.

Method: Two groups of listeners heard a series of /h/-vowel-/d/ (/hVd/) words produced by Black and White talkers from East and West North Carolina, respectively.

Results: Both Southern (North Carolina) and Midland (Indiana) listeners accurately categorized the race of all speakers with greater-than-chance accuracy; however, Western North Carolina Black talkers were categorized with the lowest accuracy, just above chance.

Conclusions: The results suggest that similarities in the speech production patterns of West North Carolina Black and White talkers affect the racial categorization of Black, but not White talkers. The results are discussed with respect to the acoustic spectral features of the voices present in the sample population.

Purpose: Deficits in the processing and production of emotional cues are well documented in the Parkinson's disease (PD) literature; however, few have ventured to explore how impairments may impact emotional language use in this population, particularly beyond the word level. Emotional language is an important multidimensional manner of communicating one's wants and needs; thus, the current study sought to explore how various aspects of language production may be impacted by the emotionality of a stimulus.

Method: Eighteen persons with PD and 22 healthy adults completed a constrained emotional sentence production task in which the affective target word was either a noun or a verb. Output was analyzed for fluency, grammaticality, completeness, and response initiation times. Cognitive (i.e., working memory [WM], inhibition, and switching) and mood (i.e., depression and apathy) measures were examined as factors influencing performance.

Results: Individuals with PD produced fewer fluent responses than healthy controls. Furthermore, they had fewer grammatical responses in their production of negative sentences and exhibited reduced information completeness when producing sentences containing positive stimuli. Group differences could not be wholly attributed to individual differences in WM or apathy.

Conclusions: Our results support those of others that document language production deficits in individuals with PD above and beyond those impairments that can be explained by the select cognitive abilities explored here. Moreover, the emotionality of the topic may impact various aspects of communicative competence in persons with PD. For instance, disease processes associated with degeneration of neural substrates important for processing negative stimuli may also impact the grammaticality of productions containing negatively valenced content. Thus, it is important to consider how individuals in this population communicate during emotional circumstances.

Supplemental material: https://doi.org/10.23641/asha.27289413.

Purpose: This study investigates the effect of voice-focus adjustments on oronasal balance and auditory feedback control of speech via analyzing spectral distribution, perceived loudness, and nasal vibrations during sustained phonation and passage reading.

Method: Twenty-five speech-language pathologists sustained /a/ and read passages with forward, backward, and natural voice focuses in quiet and noisy conditions. The low-frequency power (LFP) below 3 Hz of vocal fundamental frequency was analyzed to access audio-vocal feedback control. Long-term average spectra of speech were converted to phon spectra based on equal-loudness contours ISO 226:2003 to estimate perceived loudness of self-voice across different conditions. Nasal vibrations were also recorded using a digital accelerometer to measure oronasal coupling.

Results: Forward-focused voice enhanced the nasal acceleration and reduced LFP, suggesting that increasing the degree of oronasal coupling can improve audio-vocal feedback control compared to natural and backward-focused voices. Voice-focus adjustments were most related to average power and phon values in the 0.2- to 0.3-kHz band. In noise, perceived loudness in the 0.5- to 2.3-kHz band effectively predicted LFP, outperforming the average spectral power of the same band.

Conclusions: Voice-focus adjustments significantly impact both the acoustic transfer function of the vocal tract and the spontaneous fine-tuning of audio-vocal integration. This influence becomes particularly pronounced when sound intensity or perceived loudness is changed within the frequency range of 0.2-2.3 kHz, depending on the voice focus selected by the speakers.

Supplemental material: https://doi.org/10.23641/asha.27183483.

Purpose: This systematic review covers the current stage of research on subtle cognitive impairment with connected speech. It aims at surveying the linguistic features in use to single out those that can best identify patients with mild neurocognitive disorders (mNCDs), whose cognitive changes remain underdiagnosed.

Method: We followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines and proposed a full definition of features for the analysis of speech features. Fifty-one studies met the inclusion criteria. Most of them focused on age-related progressive diseases and included fewer than 30 subjects.

Results: A total of 384 features labeled with 335 different names was retrieved, yielding various results in discriminating individuals with mNCDs from controls.

Conclusions: This finding highlights the need for harmonized labels to further investigate mNCDs with linguistic markers. We suggest two different ways of assessing a feature's reliability. We also point out potential methodological issues that remain to be resolved, along with recommendations for reproducible research in the field.