Word Repetition Task Research Articles

The characteristics and reproducibility of motor speech functional neuroimaging in healthy controls.

Functional magnetic resonance imaging (fMRI) can improve our understanding of neural processes subserving motor speech function. Yet its reproducibility remains unclear. This study aimed to evaluate the reproducibility of fMRI using a word repetition task across two time points. Imaging data from 14 healthy controls were analysed using a multi-level general linear model. Significant activation was observed during the task in the right hemispheric cerebellar lobules IV-V, right putamen, and bilateral sensorimotor cortices. Activation between timepoints was found to be moderately reproducible across time in the cerebellum but not in other brain regions. Preliminary findings highlight the involvement of the cerebellum and connected cerebral regions during a motor speech task. More work is needed to determine the degree of reproducibility of speech fMRI before this could be used as a reliable marker of changes in brain activity.

Effects of Time Interval and Interference Manipulations on Word-Level Repetition and Naming Performance in Persons with Aphasia

Objectives: The purpose of this paper is to investigate the impact on the repetition and naming ability of Korean aphasia patients by controlling their working memory load through time intervals and interference effects using the Temple Assessment of Language and verbal Short-term memory in Aphasia (TALSA) protocol. In addition, we examined the phonological and lexical-meaning processing abilities of persons with aphasia through word repetition tasks, nonword repetition tasks, and picture naming tasks to examine phonological and lexical-meaning production abilities. Methods: Thirteen native Korean speakers with aphasia participated in the study, along with twelve control group participants. The word and nonword repetition tasks were conducted under three conditions to examine the time delay and interference effects. Each condition entailed listening to each ten words of two and three syllables. Similarly, the picture naming tasks were carried out under three conditions involving viewing ten pictures of two and three syllables each. Results: This study examined how the repetition and naming ability of persons with aphasia, i.e., the ability to producing phonemes and lexical-meaning of persons with aphasia, varies when adjusting the working memory load under time interval and interference effect conditions. This study found that the difference in performance between groups was significant for both tasks. In particular, the larger the time interval, the greater the interference effect; that is, the greater the load of working memory, the lower the performance of aphasia subjects compared to the control group. Conclusion: Since the aphasia subjects have poor working memory ability, the results of this study indicate that as the cognitive load increases, they are more affected by the ability to process phonological and semantic activations.

Characterizing Speech Errors Across Primary Progressive Apraxia of Speech Subtypes.

Apraxia of speech (AOS) is a motor speech disorder affecting articulatory planning and speech programming. When AOS is the sole manifestation of neurodegeneration, it is termed primary progressive apraxia of speech (PPAOS). Recent work has shown that there are distinct PPAOS subtypes: phonetic, prosodic, and those that do not clearly align with either (mixed). PPAOS subtypes differ with respect to the predominating motor speech difficulties, as well as disease progression and underlying pathology. Because past studies have determined PPAOS subtype based on clinical impression, the goal of the present study was to quantitatively determine the distribution of speech error types across PPAOS subtypes in a word repetition task and to investigate how word complexity affects the type and number of speech errors across PPAOS subtypes. Forty-five patients with PPAOS (13 phonetic, 23 prosodic, and nine mixed) and 45 healthy controls produced multiple repetitions of words that varied in phonetic complexity. Sound additions, deletions, and substitutions/distortions (phonetic errors) and within-word segmentations (prosodic errors) were calculated. All three PPAOS groups produced significantly more errors than controls, but the total number of errors was comparable among subtypes. The phonetic group produced more phonetic-type errors compared to the prosodic group but comparable to the mixed group. The prosodic group produced more segmentations compared to the phonetic and mixed PPAOS groups. As word complexity increased, the total number of errors increased for PPAOS patients. The phonetic and prosodic groups were more likely to produce phonetic- and prosodic-type errors, respectively, as word complexity increased. This study provides novel quantitative data showing that PPAOS subtype can be supported by the type and distribution of speech errors in a word repetition task. This may facilitate earlier, more reliable differential diagnosis and aid in disease prognosis, as PPAOS subtypes have distinct disease trajectories.

In an EFL Environment: Characteristics of Speech Sound Disorders in Children’s English Articulation

Objectives: In an EFL (English as a Foreign Language) environment like Korea, individuals learn English through education, and learning a foreign language is naturally influenced by the language system of the mother tongue. This study aimed to investigate the English speech characteristics and patterns of native language transfer in children with speech sound disorders (SSD).Methods: 20 Korean children aged 4-6 years participated in this study. The study divided participants into SSD and normal speech acquisition (NSA) groups, each comprising 10 children. Participants completed English word repetition task using the Diagnostic Evaluation of Articulation and Phonology (DEAP). Additionally, the SSD group was assessed using the Urimal Test of Articulation & Phonology (U-TAP) to compare differences in speech production based on language types. In both groups, the overall consonant accuracy, error types an error patterns in English were analyzed. English error types were categorized as substitution, vowel addition, consonant addition, vowel deletion, consonant deletion, inter-language distortion and intra-language distortion. Error patterns were further divided into developmental and non-developmental error patterns.Results: The SSD group demonstrated lower consonant accuracy compared to the NSA group in English articulation. Significant differences were observed between the two groups in vowel deletion rates and minor variations in consonant addition patterns. Error pattern analysis revealed that both groups exhibited a high proportion of stopping and final consonant deletion.Conclusion: This study directly confirmed the transfer of native language deficits in children with SSD to their English articulation and indirectly suggested that underlying deficits might impact English speech production.

Covert Contrast in Acquiring Fricatives by Preschool Children: Evidence From Najdi Arabic

Covert contrast is the statistically reliable distinction between target language phonemes produced in the process of language acquisition that is nevertheless not perceived by a native speaker of that language. This paper examines the acquisition of contrasts in four Najdi Arabic fricatives, /s/, /ʃ/, /θ/, and /ð/, and seeks to identify the most common substitutions in producing these sounds. Words were elicited from 25 preschool children (aged 3–5 years). The target words contained the studied fricative followed by either long /a:/ or short /a/ in the initial position. Praat software was used for acoustic analysis to extract the four acoustic cues: center of gravity, fricative noise duration, F1, and F2. Participants performed a word repetition task and a picture elicitation task. The results showed six cases of covert contrast, seven cases of no contrast, and 87 cases of accurate production (overt contrast). The results also revealed stopping, gliding, and affrication as substitutions in the manner of articulation, while replacement in place of articulation occurred in backing but most commonly in fronting (24 cases). The present study sought to determine implications for children’s linguistic performance, and, consequently, for language education and for planning treatment for children with speech disorders.

Word Repetition Paired With Startling Stimuli Decreases Aphasia and Apraxia Severity in Severe-to-Moderate Stroke: A Stratified, Single-Blind, Randomized, Phase 1 Clinical Trial.

This prospective, single-blinded, parallel, stratified, randomized clinical trial via telehealth aimed to investigate the impact of Startle Adjuvant Rehabilitation Therapy (START) on aphasia, apraxia of speech (AOS), and quality of life in individuals with chronic stroke. The study hypothesized that START would have a greater effect on AOS-related measures and more severe individuals. Forty-two participants with poststroke aphasia, AOS, or both were randomly assigned to the START or control group. Both groups received 77-dB GET READY and GO cues during a word repetition task for three 1-hr sessions on consecutive days. The START group additionally received 105-dB white noise GO cues during one third of trials. The Western Aphasia Battery-Revised, Apraxia Battery for Adults, Stroke Impact Scale, and Communication Outcomes After Stroke scale were administered at Day 1, Day 5, and 1-month follow-up. START improved performance on some subtests of the Western Aphasia Battery (Comprehension, Repetition, Reading) and measures of AOS (Diadochokinetic Rate, Increasing Word Length) in individuals with moderate/severe aphasia, whereas moderate/severe controls saw no changes. Individuals with mild aphasia receiving START had improved Reading, whereas mild controls saw improved Comprehension. The START group had increased mood and perceived communication recovery by Day 5, whereas controls saw no changes in quality of life. This study is the first to evaluate the impact of training with startling acoustic stimuli on clinical measures of aphasia and AOS. Our findings suggest START can enhance both nontrained speech production and receptive speech tasks in moderate/severe aphasia, possibly by reducing poststroke cortical inhibition. Our findings should be considered carefully, as our limitations include small effect sizes, within-group variability, and low completion rates for quality-of-life assessments and follow-up visits. Future studies should explore a mechanism of action, conduct larger and longer Phase 2 clinical trials, and evaluate long-term retention. https://doi.org/10.23641/asha.24093519.

Normative Values for Word Syllable Duration With Interpretation in a Large Sample of Stroke Survivors With Aphasia.

Slow speech rate and abnormal temporal prosody are primary diagnostic criteria for differentiating between people with aphasia who do and do not have apraxia of speech. We sought to identify appropriate cutoff values for abnormal word syllable duration (WSD) in a word repetition task, interpret them relative to a data set of people with chronic aphasia, and evaluate the extent to which manually derived measures could be approximated through an automated process that relied on commercial speech recognition technology. Fifty neurotypical participants produced 49 multisyllabic words during a repetition task. Audio recordings were submitted to an automated speech recognition (ASR) service (IBM Watson) to measure word duration and generate an orthographic transcription. The transcribed words were compared to a lexical database, and the number of syllables was identified. Automatic and manual measures were compared for 50% of the sample. Results were interpreted relative to WSD scores from an existing data set of 195 people with mostly chronic aphasia. ASR correctly identified 83% of target words and 98% of target syllable counts. Automated word duration calculations were longer than manual measures due to imprecise cursor placement. Upon applying regression coefficients to the automated measures and examining the frequency distributions for both manual and estimated measures, a WSD of 303-316 ms was found to indicate longer-than-normal performance (corresponding to the 95th percentile). With this cutoff, 40%-45% of participants with aphasia in our comparison sample had an abnormally long WSD. We recommend using a rounded WSD cutoff score between 303 and 316 ms for manual measures. Future research will focus on customizing automated WSD methods to speech samples from people with aphasia, identifying target words that maximize production and measurement reliability, and developing WSD standard scores based on a large participant sample with and without aphasia.

Acoustic analysis of lexical stress in Greek preschool children

Lexical stress carries significant functional load in Greek; there are several pairs and even triplets of words that are differentiated only by stress position. Greek stressed vowels are longer and have a greater amplitude compared to their unstressed counterparts. Lexical stress is also indirectly signalled by pitch movement (Arvaniti, 2007). The trajectory of lexical stress development has received little attention, both in Greek and in the international literature, especially regarding the acoustic analysis of prominence. Therefore, the aim of this study was to investigate the acoustic realisation of stress during Greek acquisition. To that end, 24 typically developing children aged 4;7 to 6;4 (years;months), and 24 adults aged 20 to 25, carried out a word repetition task involving 20 minimal stress pairs (15 real words and five non-words). Duration, intensity and F0 variation, indices of the relative prominence of stressed to unstressed vowels, were calculated. Overall, although the use of the intensity cue for lexical stress did not differ significantly between the two groups, children tended to use the vowel duration cue to a lesser extent than adults to signal lexical stress position. On the other hand, F0 variation indices were significantly higher in the children’s data. Additionally, the acoustic analysis indicated that children utilized the pattern of devoicing unstressed vowels, a specific type of vowel reduction optionally applied in Greek, much more extensively than adults. Finally, although for the most part the word productions carried unequivocal and correct lexical stress, in a few cases children, contrary to adults, had difficulties signalling lexical stress position in a perceptually transparent manner. This study is one of the few attempts to describe the acoustic characteristics of lexical stress in Greek typical development.

The syllable as a fundamental sub-lexical unit in phonological paraphasias: evidence from Spanish-speaking aphasic patients

ABSTRACT Background Considering that the syllable is a well-defined unit in the Spanish language, we assume that it could be analyzed at the core of phonological paraphasias. Aims Identify if the characteristics of the Spanish syllable system are reflected in the production of phonological errors among Spanish-speaking aphasic patients. Methods & Procedures Twenty-four Spanish-speaking aphasic patients with different aetiology, severity, and type of aphasia participated in the study. We designed Word and Pseudoword Repetition Tasks controlling for stimuli length, syllable structure frequency, and syllable position. Outcomes & Results The production of paraphasias evidences an effect of syllable complexity and syllable frequency, since the CV syllable structure which is the simplest but also the most common one in Spanish, was more resistant to errors. Stimulus length and stimuli lexicality effects were evident since monosyllabic stimuli and words (opposed to pseudowords) triggered fewer errors, respectively. Also, we observed an interaction of length/lexicality, where polysyllabic pseudowords were related to a higher number of errors. Finally, results revealed a strong correlation between the relative frequency of syllable structures in Spanish and the percentage of syllable structures in phonemic paraphasias. Conclusions The repetition of words and pseudowords by these Spanish-speaking aphasic patients confirm that their phonological errors are related to the syllabic system of the Spanish language. This finding has implications when assessing Spanish-speaking aphasic patients.

ThumbAir

Typing while wearing a standalone Head Mounted Display (HMD)---systems without external input devices or sensors to support text entry---is hard. To address this issue, prior work has used external trackers to monitor finger movements to support in-air typing on virtual keyboards. While performance has been promising, current systems are practically infeasible: finger movements may be visually occluded from inside-out HMD based tracking systems or, otherwise, awkward and uncomfortable to perform. To address these issues, this paper explores an alternative approach. Taking inspiration from the prevalence of thumb-typing on mobile phones, we describe four studies exploring, defining and validating the performance of ThumbAir, an in-air thumb-typing system implemented on a commercial HMD. The first study explores viable target locations, ultimately recommending eight targets sites. The second study collects performance data for taps on pairs of these targets to both inform the design of a target selection procedure and also support a computational design process to select a keyboard layout. The final two studies validate the selected keyboard layout in word repetition and phrase entry tasks, ultimately achieving final WPMs of 27.1 and 13.73. Qualitative data captured in the final study indicate that the discreet movements required to operate ThumbAir, in comparison to the larger scale finger and hand motions used in a baseline design from prior work, lead to reduced levels of perceived exertion and physical demand and are rated as acceptable for use in a wider range of social situations.

Comparing methods of analysis in pupillometry: application to the assessment of listening effort in hearing-impaired patients

Numerous studies showed that task-evoked pupil dilation is an objective marker of cognitive activity and listening effort. However, these studies differ in their experimental and analysis methods. Whereas most studies focus on a single method, the present study sought to compare different pupil-dilation data analysis methods, including different normalization techniques, baseline periods, and baseline durations, in order to assess their influence on the outcomes of pupillometry results obtained in an auditory task. To that purpose, we used pupillometry data recorded in response to words in noise in hearing-impaired individuals. The start-time of the baseline relative to stimulus timing turned out to have a significant influence on conclusions. In particular, a significant interaction in the effects of signal-to-noise ratio and hearing-aid use on pupil dilation was observed when the baseline period used started early relative to the word—an effect likely related to anticipatory, pre-stimulus cognitive processes, such as attention mobilization. This was the case even with only correct-response trials included in analyses, so that any confounding effect of performance in the word-repetition task was eliminated. Different normalization methods and baseline durations showed similar results, however the use of z-score transformation homogenized variability across conditions without affecting the qualitative aspect of the results. The consistency of results regardless of normalization methods, and the fact that differences in pupil dilation and subjective measures of listening effort could be observed despite perfect performance in the task, underlines the relevance of pupillometry as an objective measure of listening effort.

Production of Vowel Reduction by Mexican Learners of English as L2 and Russian as L3

AbstractIn this study, we examined to what extent cross-linguistic influence is observed in the production of unstressed vowels in Mexican learners of L2 English and L3 Russian. Phonological spectral vowel reduction is a widespread process present in both English and Russian, but not in Spanish. In total, 18 Mexican learners, six American speakers, five Russian speakers and six Mexican speakers performed a delayed word repetition task and a sentence completion task. Euclidean distances and temporal values were measured to assess vowel reduction in 1,192 tokens. Mexican learners showed hybrid values of vowel reduction in both foreign languages: while they tended to use quality cues in the case of the L2, they relied on duration cues in the case of the L3. Our results do not show any direct evidence of cross-linguistic influence of temporal values or vowel quality from the L1 or the L2 on the L3. We examine these findings in light of similar studies and current L3 acquisition models.

Training the pronunciation of L2 vowels under different conditions: the use of non-lexical materials and masking noise.

The current study extends traditional perceptual high-variability phonetic training (HVPT) in a foreign language learning context by implementing a comprehensive training paradigm that combines perception (discrimination and identification) and production (immediate repetition) training tasks and by exploring two potentially enhancing training conditions: the use of non-lexical training stimuli and the presence of masking noise during production training. We assessed training effects on L1-Spanish/Catalan bilingual EFL learners' production of a difficult English vowel contrast (/æ/-/ʌ/). The participants (N=62) were randomly assigned to either non-lexical (N=24) or lexical (N=24) training and were further subdivided into two groups, one trained in noise (N=12) and one in silence (N=12). An untrained control group (N=14) was also tested. Training gains, measured through spectral distance scores (Euclidean distances) with respect to native speakers' productions of /æ/ and /ʌ/, were assessed through delayed word and sentence repetition tasks. The results showed an advantage of non-lexical training over lexical training, detrimental effects of noise for participants trained with nonwords, but not for those trained with words, and less accurate production of vowels elicited in isolated words than in words embedded in sentences, where training gains were only observable for participants trained with nonwords.

Syntactic development and verbal short-term memory of children with autism spectrum disorders having intellectual disabilities and children with down syndrome.

Previous studies suggest that syntactic development in children with intellectual disabilities (ID) is positively correlated with verbal short-term memory (VSTM). This study investigated the characteristics of syntactic development and their relationships of VSTM in children with ID based on type. The participants were children with ID (N = 34), including 14 children with autism spectrum disorders (ASD), 20 with Down syndrome (DS), with chronological ages from 8 years 10 months to 18 years 4 months and nonverbal mental ages (MA) of over 4 years, and typically developing (TD) children (N = 21) with chronological ages from 5 years 0 months to 5 years 10 months. They were assessed using VSTM, syntactic comprehension, and expression tasks. The results showed that both the ASD and DS groups performed significantly lower on the syntactic comprehension task and the syntactic expression task than the TD group with the same nonverbal MA in the complex aspect of grammatical structure. In the VSTM task, the ASD group showed significantly lower performance in sentence and story repetition tasks than the TD group of the same nonverbal MA. The DS group showed significantly lower performance in forward digit span, and word, nonword, sentence, and story repetition tasks than the TD group of the same nonverbal MA. These results suggest that children with ASD have difficulty in understanding and remembering linguistic information with complex semantic structures, and children with DS have a small capacity for VSTM, affecting their syntactic development.

Effects of Device Limitations on Acquisition of the /t/-/k/ Contrast in Children With Cochlear Implants.

The present study investigated how development of the /t/-/k/ contrast is affected by the unique perceptual constraints imposed on young children using cochlear implants (CIs). We hypothesized that children with CIs would demonstrate unique patterns of speech acquisition due to device limitations, rather than straightforward delays due to a lack of auditory input in the first year of life before implantation. This study focused on the contrast between /t/ and /k/ because it is acquired early in the sequence of development, requires less advanced motor control than later-acquired place contrasts, is differentiated by spectral cues (which are particularly degraded when processed by CIs), and is not easily differentiated by visual cues alone. Furthermore, perceptual confusability between /t/ and /k/ may be exacerbated in front-vowel contexts, where the spectral energy for /k/ is shifted to higher frequencies, creating more spectral overlap with /t/. Children with CIs (n = 26; ages 31 to 66 mo) who received implants around their first birthdays were matched to peers with normal hearing (NH). Children participated in a picture-prompted auditory word-repetition task that included over 30 tokens of word-initial /t/ and /k/ consonants. Tokens were balanced across front-vowel and back-vowel contexts to assess the effects of coarticulation. Productions were transcribed and coded for accuracy as well as the types of errors produced (manner of articulation, voicing, or place of articulation errors). Centroid frequency was also calculated for /t/ and /k/ tokens that were produced correctly. Mixed-effects models were used to compare accuracy, types of errors, and centroid frequencies across groups, target consonants, and vowel contexts. Children with CIs produced /t/ and /k/ less accurately than their peers in both front- and back-vowel contexts. Children with CIs produced /t/ and /k/ with equal accuracy, and /k/ was produced less accurately in front-vowel contexts than in back-vowel contexts. When they produced errors, children with CIs were more likely to produce manner errors and less likely to produce voicing errors than children with NH. Centroid frequencies for /t/ and /k/ were similar across groups, except for /k/ in front-vowel contexts: children with NH produced /k/ in front-vowel contexts with higher centroid frequency than children with CIs, and they produced /k/ and /t/ with equal centroid frequencies in front-vowel contexts. Children with CIs not only produced /t/ and /k/ less accurately than peers with NH, they also demonstrated idiosyncratic patterns of acquisition, likely resulting from receiving degraded and distorted spectral information critical for differentiating /t/ and /k/. Speech-language pathologists should consider perceptual confusability of consonants (and their allophonic variations) during their assessment and treatment of this unique population of children.

Phonological Short-Term Memory Impairment in Children with Down Syndrome

Abstract Background: Children with Down Syndrome commonly suffer from phonological and other language disorders which have been partly attributed to underlying deficit in phonological short term memory. Its evaluation was previously confined to non word repetition and/or forward digit span tasks. Aim of Study: To assess phonological short term memory in children with Down Syndrome with mild degree of intel-lectual disability in comparison with non syndromic children with mild degree of intellectual disability to find out any possible correlation between Down Syndrome and phonolog-ical short term memory deficits through comprehensive eval-uation. Subjects and Methods: This case control study has been conducted on 40 children (20 Down Syndrome children with mild degree of intellectual disability, 20 non syndromic children with mild degree of intellectual disability with matched mental age). All of them underwent psychometric evaluation, audiological evaluation, language evaluation using Arabic version of Modified Preschool Language Scale-4th edition (PLS-4), and Arabic version of Phonological Short Term Memory Test (PSTM). Results: Down Syndrome group scored significantly lower than non syndromic children with mild degree of intellectual disability in all items of phonological short term memory test; digit span, syllable repetition, non sense word repetition, dissimilar word set recall, similar word set recall, total score (p-value 0.000, 0.001, 0.004, 0.000, 0.000, 0.000 respectively) and language test; expressive abilities was lower in Down syndrome children (p-value 0.002) but both groups were equal in their receptive abilities (p-value 0.054). Conclusion: Children with Down Syndrome scored below expected for phonological short term memory and their pho-nological store was extensively impaired.

The Strategies and Assignment of Teaching and Learning of Speaking Ability in an Educational Institution

This research is conducted to describe the implementation of teaching and learning strategies and the assignment of innovative speaking ability for formal school. The research method used in this study is qualitative research with library research. The learning strategies for the students may consist of direct and indirect method. The teaching strategies can be a part of the activities available done in the class, such as; role plays, simulation, telling story, interview, conversation, discussion, and using the target language outside the classroom. The assignment form of speaking ability may be grouped as; Imitative Speaking (word repetition task and phone pass test), Intensive Speaking (directed response test and read-aloud test), responsive speaking (question and answer and giving interaction and direction), interactive speaking (interview and discussion conversation), and extensive speaking (oral presentation and retelling story and news)

Speech Metrics and Samples That Differentiate Between Nonfluent/Agrammatic and Logopenic Variants of Primary Progressive Aphasia.

Purpose Of the three currently recognized variants of primary progressive aphasia, behavioral differentiation between the nonfluent/agrammatic (nfvPPA) and logopenic (lvPPA) variants is particularly difficult. The challenge includes uncertainty regarding diagnosis of apraxia of speech, which is subsumed within criteria for variant classification. The purpose of this study was to determine the extent to which a variety of speech articulation and prosody metrics for apraxia of speech differentiate between nfvPPA and lvPPA across diverse speech samples. Method The study involved 25 participants with progressive aphasia (10 with nfvPPA, 10 with lvPPA, and five with the semantic variant). Speech samples included a word repetition task, a picture description task, and a story narrative task. We completed acoustic analyses of temporal prosody and quantitative perceptual analyses based on narrow phonetic transcription and then evaluated the degree of differentiation between nfvPPA and lvPPA participants (with the semantic variant serving as a reference point for minimal speech production impairment). Results Most, but not all, articulatory and prosodic metrics differentiated statistically between the nfvPPA and lvPPA groups. Measures of distortion frequency, syllable duration, syllable scanning, and-to a limited extent-syllable stress and phonemic accuracy showed greater impairment in the nfvPPA group. Contrary to expectations, classification was most accurate in connected speech samples. A customized connected speech metric-the narrative syllable duration-yielded excellent to perfect classification accuracy. Discussion Measures of average syllable duration in multisyllabic utterances are useful diagnostic tools for differentiating between nfvPPA and lvPPA, particularly when based on connected speech samples. As such, they are suitable candidates for automatization, large-scale study, and application to clinical practice. The observation that both speech rate and distortion frequency differentiated more effectively in connected speech than on a motor speech examination suggests that it will be important to evaluate interactions between speech and discourse production in future research.

Heterogeneity of repetition abilities in logopenic variant primary progressive aphasia.

ABSTRACT.The differential diagnosis of primary progressive aphasia (PPA) is challenging due to overlapping clinical manifestations of the different variants of the disease. This is particularly true for the logopenic variant of PPA (lvPPA), in which such overlap was reported with regard to impairments in repetition abilities. In this study, four individuals with lvPPA underwent standard neuropsychological and language assessments. The influence of psycholinguistic variables on their performance of in word, nonword and sentence repetition tasks was also specifically explored. Some level of heterogeneity was found in cognitive functions and in language. The four participants showed impairment in sentence repetition in which their performance was negatively affected by semantic reversibility and syntactic complexity. This study supports the heterogeneity of lvPPA with respect to the cognitive and linguistic status of participants. It also shows that sentence repetition is influenced not only by length, but also by semantic reversibility and syntactic complexity, two psycholinguistic variables known to place additional demands on phonological working memory.

Consonant and vowel articulation accuracy in younger and middle-aged Spanish healthy adults.

Children acquire vowels earlier than consonants, and the former are less vulnerable to speech disorders than the latter. This study explores the hypothesis that a similar contrast exists later in life and that consonants are more vulnerable to ageing than vowels. Data was obtained with two experiments comparing the speech of Younger Adults (YAs) and Middle-aged Adults (MAs). In the first experiment an Automatic Speech Recognition (ASR) system was trained with a balanced corpus of 29 YAs and 27 MAs. The productions of each speaker were obtained in a Spanish language word (W) and non-word (NW) repetition task. The performance of the system was evaluated with the same corpus used for training using a cross validation approach. The ASR system recognized to a similar extent the Ws of both groups of speakers, but it was more successful with the NWs of the YAs than with those of the MAs. Detailed error analysis revealed that the MA speakers scored below the YA speakers for consonants and also for the place and manner of articulation features; the results were almost identical in both groups of speakers for vowels and for the voicing feature. In the second experiment a group of healthy native listeners was asked to recognize isolated syllables presented with background noise. The target speakers were one YA and one MA that had taken part in the first experiment. The results were consistent with those of the ASR experiment: the manner and place of articulation were better recognized, and vowels and voicing were worse recognized, in the YA speaker than in the MA speaker. We conclude that consonant articulation is more vulnerable to ageing than vowel articulation. Future studies should explore whether or not these early and selective changes in articulation accuracy might be caused by changes in speech perception skills (e.g., in auditory temporal processing).