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Background: Spoken discourse production has been increasingly recognised as an important source for assessing language competence of persons with aphasia (PWA). Most linguistic measures rely on transcripts of spoken discourse, so they have seldom been used in clinical practice. Thus, there is a need for standardized and norm-referenced measures that can be easily applied in clinical settings. Aims: The present study aims to develop core lexicon lists for Mandarin Chinese PWA using AphasiaBank data elicited with different discourse production tasks and test their validity in detecting language deficiency. Methods & Procedures: We selected seven semispontaneous discourse tasks within three major task types, i.e., picture descriptions, procedural discourse and story narrative, for core lexicon list development and for examining task type effects. Transcripts from 61 control speakers were split into two sets with age – and education matched: one set (n = 43) as a normative sample used to generate the core lexicon lists and the other (n = 18) as a healthy control group served as a baseline for comparison with PWA productions. Transcripts of 18 age- and education- matched PWA were retrieved from the AphasiaBank database. We selected the top 30 words with the widest distribution in the normative sample to generate core lexicon lists. Then for both PWA and control groups, we calculated agreement percentage as core lexicon scores. Outcomes & Results: Core lexicon scores of PWA were significantly lower than the control group participants for all seven tasks and positively correlated with aphasia severity for two story narrative tasks, suggesting that story narrative tasks were more effective in assessing discourse productions compared with picture and procedural descriptions. In addition, core lexicon scores also correlated with lexical diversity (R scores) and discourse informativeness (Correct Information Units) for all seven tasks. Conclusions & Implications: Core lexicon scores can effectively distinguish discourse production by Mandarin PWA and healthy controls and they reflect lexical diversity and informativeness of discourse. Our findings, thus, have clinical implications in that these lists could serve as an alternative transcription-less approach in quick Mandarin PWA discourse production assessment. [ABSTRACT FROM AUTHOR]

This paper presents exploratory research on temporally dynamic patterns of vowel nasalization from two speakers of Arabana. To derive a dynamic measure of nasality, we use gradient tree boosting algorithms to statistically learn the mapping between acoustics and vowel nasality in a speaker-specific manner. Three primary findings emerge: (1) NVN contexts exhibit nasalization throughout the entirety of the vowel interval, and we propose that a similar co-articulatory realization previously acted to resist diachronic change in this environment; (2) anticipatory vowel nasalization is nearly as extensive as carryover vowel nasalization, which is contrary to previous claims; and (3) the degree of vowel nasalization in word-initial contexts is relatively high, even in the #_C environment, suggesting that the ongoing sound change *#ŋa > #a has involved the loss of the oral constriction associated with ŋ but not the complete loss of the velum gesture. [ABSTRACT FROM AUTHOR]

The present study examined how native phonological and phonetic factors in non-native speech perception (Perceptual Assimilation Model [PAM]: Best, 1995) affect non-native imitation of Thai tones by Thai-naïve Mandarin and Vietnamese participants, and how memory load and stimulus variability shift the balance between phonological versus phonetic modes (Automatic Selective Perception model [ASP]: Strange, 2011) in imitation. Although overall imitation was quite good, native phonological influences, as reflected in Categorised versus Uncategorised assimilation types in a prior perception study with the same participants (Chen, Antoniou, & Best, 2023), constrained non-native tone imitations. Residual perceptual sensitivity to phonetic differences between the target stimuli and native tones, as reflected in percent choice and goodness ratings in assimilation, also affected imitation. Effects of stimulus variability and memory load were restricted and interacted with specific tones for each participant group. Imitations were generally more accurate under low memory load, constant talker and vowel conditions, consistent with a more phonetic mode of perception. Imitation accuracy decreased under high memory load, variable talker and vowel conditions, consistent with a more phonological mode of perception. Results support the PAM and ASP accounts of native phonological and phonetic effects in non-native perception and extend them to non-native tone imitation. [ABSTRACT FROM AUTHOR]

BackgroundAimMethods & ProceduresOutcomes & ResultsConclusionsThe classical aphasia taxonomy has been incorporated into several widely utilised aphasia assessment tools, such as the Western Aphasia Battery (WAB). Validation of the WAB’s classification typically involves comparing it with statistical clustering analysis results, using overall agreement rates as the referential index. Nevertheless, previous studies have documented diverse agreement rates. The classification function of the Mandarin version of the revised WAB (WAB-R) has not been validated. Additionally, the discussion on validating classification function is inadequate.The current study adopts the argument-based validation framework to validate the classification function of the Mandarin version of the WAB-R and discuss the efficacy of using cluster analysis as evidence for the validation.A validation argument for the classification function was developed, utilising the k-means cluster analysis and within-group linkage cluster analysis as statistical procedures. WAB-R testing score data were collected from 122 Mandarin-speaking persons with acquired aphasia (non-acute). Eight clusters were expected to be generated from statistical procedures as a confirmatory test. To explore the impact of cluster numbers, solutions of generating six and ten clusters were conducted for comparative analysis. The potential reasons for mismatches were analysed. A proposed modified fluency scale (raising the cutoff score from 4 to 5) was also tested on the current dataset.Under the solution of eight clusters, the overall agreement was 62.3% with the k-means cluster analysis and 56.6% with the within-group linkage cluster analysis. Agreement rates slightly increased with the number of clusters in the within-group linkage method and remained almost unchanged in the k-means method. Anomic aphasia presented the highest agreements, while the agreements of other subtypes varied across different solutions. The fundamental differences between the clustering algorithm and the rationale of the WAB-R classification criteria were the primary reason for mismatched cases, undermining the reliability of the validation procedure. The modified fluency scale was found to significantly improve the overall agreement rates.The classification function of the WAB-R’s Mandarin adaptation was considered acceptable under the current method. The validation argument is suggested to be modified to enhance the rationale as the statistical cluster analysis showed reliability issues when being solely employed for validation. The mismatch rate did not form direct challenges to the validity of the classification function. Additionally, modifications to the classification criteria are suggested for further exploration as the modified fluency scale has demonstrated positive results. [ABSTRACT FROM AUTHOR]