Measuring word retrieval in narrative discourse: core lexicon in aphasia

Connected Speech Fluency in Poststroke and Progressive Aphasia: A Scoping Review of Quantitative Approaches and Features

PURPOSE

Speech fluency has important diagnostic implications for individuals with poststroke aphasia (PSA) as well as primary progressive aphasia (PPA), and quantitative assessment of connected speech has emerged as a widely used approach across both etiologies. The purpose of this review was to provide a clearer picture on the range, nature, and utility of individual quantitative speech/language measures and methods used to assess connected speech fluency in PSA and PPA, and to compare approaches across etiologies.

METHOD

We conducted a scoping review of literature published between 2012 and 2022 following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines. Forty-five studies were included in the review. Literature was charted and summarized by etiology and characteristics of included patient populations and method(s) used for derivation and analysis of speech/language features. For a subset of included articles, we also charted the individual quantitative speech/language features reported and the level of significance of reported results.

RESULTS

Results showed that similar methodological approaches have been used to quantify connected speech fluency in both PSA and PPA. Two hundred nine individual speech-language features were analyzed in total, with low levels of convergence across etiology on specific features but greater agreement on the most salient features. The most useful features for differentiating fluent from nonfluent aphasia in both PSA and PPA were features related to overall speech quantity, speech rate, or grammatical competence.

CONCLUSIONS

Data from this review demonstrate the feasibility and utility of quantitative approaches to index connected speech fluency in PSA and PPA. We identified emergent trends toward automated analysis methods and data-driven approaches, which offer promising avenues for clinical translation of quantitative approaches. There is a further need for improved consensus on which subset of individual features might be most clinically useful for assessment and monitoring of fluency.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.25537237.

Tamoxifen Effects on Cognition and Language in Women with Breast Cancer

Cognitive changes following adjuvant treatment for breast cancer (BC) are well documented following chemotherapy. However, limited studies have examined cognitive and/or language functions in chemotherapy-naive women with BC taking tamoxifen (TAM). Using ambulatory cognitive assessment, we investigated the trajectory of cognitive and language changes during early period of adjuvant endocrine treatment (TAM) in women with BC at two time periods (pretreatment and 2 months after treatment began). Four women with BC and 18 cognitively healthy age-matched controls completed three cognitive tasks using smartphones, during a short time period (5 days) and repeated them at two time periods. To determine language ability, language samples were collected at two time periods, where the participants described two stories from two wordless picture books and samples were assessed using core lexicon analyses. Wilcoxon-signed rank tests were computed to identify differences in linguistic and cognitive performances of both the groups at two time periods. No significant within-group or between-group differences were seen on the cognitive and language tasks at the two time periods; however, women with BC performed more poorly compared to the control group. We did see decline in some women with BC and not in others, in cognition and language during initial course of TAM treatment. However, the approach we used to assess these changes is valuable and innovative. This approach will help refine current research paradigms for determining cognitive and linguistic changes and will help determine if women with BC might require language intervention in the future.

Core lexicon in aphasia: A longitudinal study

Background

General consensus exists between clinicians as to the incorporation of discourse outcome measures into language assessment for persons with aphasia (PWA). The development of core lexicon measures (CoreLex) has enabled clinicians to reduce time and labor intensive preparatory work for discourse analysis, which has been considered as an alternative measure to quantify word retrieval ability in discourse in a clinical context. Although previous studies have investigated the quality of the measure, CoreLex has rarely been longitudinally explored.

Aims

We aimed to investigate the adequacy of CoreLex to document linguistic changes in PWA over time. Specifically, we examined (1) whether natural language recovery from acute to chronic stages is manifested differentially by tasks and (2) the extent to which the ability to retrieve words in isolation predicts the ability to retrieve words in context.

Methods

A total of 19 PWA participated in the study. They completed a language assessment including confrontation naming tasks (Boston Naming Test [BNT] and Hopkins Action Naming Assessment [HANA]) and a picture description task using the Cookie Theft picture at acute and chronic stages. Discourse samples from the picture description task were quantified using CoreLex.

Results

We found significant differences across tasks and time-points by PWA. Moderate correlations between the confrontation naming tasks and CoreLex were found at the acute stage but not at the chronic stage. Additionally, McNemar's tests demonstrated a significant difference in PWA's performance in CoreLex from the acute to the chronic stages.

Conclusions

Our findings show that performance by PWA improves over time on all tasks, but language gains are manifested differentially by tasks. Performance in confrontation naming moderately predicts word retrieval in context acutely. However, lack of correlations between confrontation naming tasks and CoreLex later endorse inadequacy of using confrontation naming tasks as a proxy measure for discourse-level performance and improvement for PWA.

Quality of Measurement in Core Lexicon Measures

PURPOSE

Core lexicon measures have received growing attention in research. They are intended to provide clinicians with a clinician-friendly means to quantify word retrieval ability in discourse based on normal expectations of discourse production for specific discourse elicitation tasks. To date, different criteria have been used to develop core lexicon measures by groups of researchers. The need for statistical guidance in pursuit of the psychologically robust measure has been recognized.

AIMS

This study was to investigate the best criterion for accurate measurement. Specifically, we focused on two criteria (frequency vs. percentage) that have previously been used for the development of core lexicon measures.

METHOD

Core lexicon measures consisting of five different checklists by word class (verbs, nouns, adjectives, adverbs, and function words) and developed by the two criteria were applied to language samples produced by 470 cognitively healthy adults. Performance in word retrieval ability at the discourse level was modeled as a latent variable based on the observed proportions of the production of core lexicon items in two different sets of core lexicon measures using structural equation modeling.

RESULTS

Results indicated that both criterion for core lexicon measures capture word retrieval ability in discourse. Greater residual variances were found in the core lexicon measure established by the percentage criterion compared to the one established by the frequency criterion. This indicates that the measure based on the percentage criterion is more affected by measurement errors.

CONCLUSIONS

The findings provide evidence that the frequency criterion is better to use for the development of core lexicon measures for core nouns, verbs, adjectives, and adverbs, but not for function words. However, our findings are limited to core lexicon measures based on language samples elicited by wordless picture books. This may not be easily applied to other core lexicon measures that use different discourse elicitation tasks due to the difference in quality and quantity of language samples. Ideally, the same approach should be replicated to evaluate the appropriateness of respective criteria in the development of core lexicon measures.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.20304144.

Validation of an Automated Procedure for Calculating Core Lexicon From Transcripts

PURPOSE

The aim of this study was to advance the use of structured, monologic discourse analysis by validating an automated scoring procedure for core lexicon (CoreLex) using transcripts.

METHOD

Forty-nine transcripts from persons with aphasia and 48 transcripts from persons with no brain injury were retrieved from the AphasiaBank database. Five structured monologic discourse tasks were scored manually by trained scorers and via automation using a newly developed CLAN command based upon previously published lists for CoreLex. Point-to-point (or word-by-word) accuracy and reliability of the two methods were calculated. Scoring discrepancies were examined to identify errors. Time estimates for each method were calculated to determine if automated scoring improved efficiency.

RESULTS

Intraclass correlation coefficients for the tasks ranged from .998 to .978, indicating excellent intermethod reliability. Automated scoring using CLAN represented a significant time savings for an experienced CLAN user and for inexperienced CLAN users following step-by-step instructions.

CONCLUSIONS

Automated scoring of CoreLex is a valid and reliable alternative to the current gold standard of manually scoring CoreLex from transcribed monologic discourse samples. The downstream time saving of this automated analysis may allow for more efficient and broader utilization of this discourse measure in aphasia research. To further encourage the use of this method, go to https://aphasia.talkbank.org/discourse/CoreLexicon/ for materials and the step-by-step instructions utilized in this project.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.20399304.

An efficient, accurate and clinically-applicable index of content word fluency in Aphasia

Background

Despite the clinical importance of assessing the efficiency and accuracy of fluency in terms of content words production during connected speech, assessments based on discourse tasks are very time-consuming and thus not clinically feasible.

Aims

(1) Examine the relationship between single-word naming and word retrieval during discourse production. (2) Investigate the relationship between word retrieval and content word fluency derived from a simple versus naturalistic discourse tasks. (3) Develop and validate an efficient and accurate index of content word fluency that is clinically viable.

Methods

Two discourse tasks (simple picture description and naturalistic storytelling narrative) were collected from 46 participants with post-stroke aphasia, and 20 age/education matched neuro-typical controls. Each discourse sample was fully transcribed and quantitative analysis was applied to each sample to measure word retrieval and content word fluency. Three single-word naming tasks were also administered to each participant with aphasia.

Results

Correlational analyses between single-word naming and word retrieval in connected speech revealed weak/moderate relationships. Conversely, strong correlations were found between measures derived from simple picture description against naturalistic storytelling discourse tasks. Moreover, we derived a novel, transcription-less index of content word fluency from the discourse samples of an independent group (neuro-typical controls), and then we validated this index across two discourse tasks in the tested group (persons with aphasia). Correlation and regression analyses revealed extremely strong relationships between participants' (neuro-typical controls and persons with aphasia) scores on the novel index and measures of content word fluency derived from the formal transcription and quantitative analyses of discourse samples, indicating high accuracy and validity of the new index.

Conclusions

Simple picture description rather than picture naming provides a better estimate of word retrieval in naturalistic connected speech. The novel developed index is transcription-less and can be implemented online to provide an accurate and efficient measure of content word fluency. Thus, it is viable during clinical practice for assessment purposes, and possibly as an outcome measure to monitor therapy effectiveness, which can also be used in randomised clinical trials.

Written Discourse Task Helps to Identify Progression from Mild Cognitive Impairment to Dementia

PURPOSE

We aimed to investigate: (1) the clinical, diagnostic value of a written discourse task, and (2) the relationship between executive functions and written discourse within the spectrum of individuals with mild cognitive impairment (MCI).

METHOD

To determine whether written discourse performance predicts clinical course among individuals with MCI, we retrospectively classified individuals with MCI as converters (N = 26) who were later diagnosed with dementia or as a stable MCI group (N = 45). We quantified core word measures from written discourse samples obtained from the Cookie Theft picture description task.

RESULT

Written discourse measures differentiated converters from the stable MCI group. Converters produced a fewer number of core words than the stable MCI group. A measure of executive function significantly predicted performance on the production of core words in written discourse for the converters. In a multivariable regression, production of core words remained the only explanatory variable closely associated with the progression to dementia in MCI.

CONCLUSION

Written discourse tasks can predict the likelihood of MCI progressing to dementia, independently of recall and an executive function measure. Correlational results suggest that written discourse performance was associated with executive function as measured by the Trail Making Test. Our findings emphasize the usefulness of including written discourse tasks in language assessment batteries targeting preclinical dementia populations.

Assessment of language impairment and function

This chapter is written for the qualified neurologist or related professional working with persons who have had a stroke or other sudden brain injury. It is critical that the presence of aphasia is detected, no matter how mild the presentation, and to support that assertion, this chapter highlights the plight of persons with latent aphasia. At the individual level, the impact of aphasia is devastating, with overwhelming evidence that aphasia negatively impacts psychosocial outcomes. At the global level, sensitive detection and accurate diagnosis of aphasia are critical for accurate characterization and quantification of the global burden of aphasia. The word "LANGUAGE" is leveraged as an acronym to create a useful and memorable checklist to guide navigation of aphasia screening and assessment: it begins with the definition of language (L), followed by the definition and diagnostic criteria for aphasia (A). Then language abilities and characteristics to be considered in assessment are presented: naming (N); grammar and syntax (G); unintelligible words, jargon, and paraphasias (U); auditory comprehension and repetition (A); graphemic abilities-reading and writing (G); and everyday communication and discourse (E). Recommendations for improving procedural adherence are provided, and a list of potential brief assessment measures are introduced.

Enhancing the Classification of Aphasia: A Statistical Analysis Using Connected Speech

BACKGROUND

Large shared databases and automated language analyses allow for the application of new data analysis techniques that can shed new light on the connected speech of people with aphasia (PWA).

AIMS

To identify coherent clusters of PWA based on language output using unsupervised statistical algorithms and to identify features that are most strongly associated with those clusters.

METHODS & PROCEDURES

Clustering and classification methods were applied to language production data from 168 PWA. Language samples were from a standard discourse protocol tapping four genres: free speech personal narratives, picture descriptions, Cinderella storytelling, procedural discourse.

OUTCOMES & RESULTS

Seven distinct clusters of PWA were identified by the K-means algorithm. Using the random forests algorithm, a classification tree was proposed and validated, showing 91% agreement with the cluster assignments. This representative tree used only two variables to divide the data into distinct groups: total words from free speech tasks and total closed class words from the Cinderella storytelling task.

CONCLUSION

Connected speech data can be used to distinguish PWA into coherent groups, providing insight into traditional aphasia classifications, factors that may guide discourse research and clinical work.

Standardizing Assessment of Spoken Discourse in Aphasia: A Working Group With Deliverables

Purpose The heterogeneous nature of measures, methods, and analyses reported in the aphasia spoken discourse literature precludes comparison of outcomes across studies (e.g., meta-analyses) and inhibits replication. Furthermore, funding and time constraints significantly hinder collecting test-retest data on spoken discourse outcomes. This research note describes the development and structure of a working group, designed to address major gaps in the spoken discourse aphasia literature, including a lack of standardization in methodology, analysis, and reporting, as well as nominal data regarding the psychometric properties of spoken discourse outcomes. Method The initial initiatives for this working group are to (a) propose recommendations regarding standardization of spoken discourse collection, analysis, and reporting in aphasia, based on the results of an international survey and a systematic literature review and (b) create a database of test-retest spoken discourse data from individuals with and without aphasia. The survey of spoken discourse collection, analysis, and interpretation procedures was distributed to clinicians and researchers involved in aphasia assessment and rehabilitation from September to November 2019. We will publish survey results and recommend standards for collecting, analyzing, and reporting spoken discourse in aphasia. A multisite endeavor to collect test-retest spoken discourse data from individuals with and without aphasia will be initiated. This test-retest information will be contributed to a central site for transcription and analysis, and data will be subsequently openly curated. Conclusion The goal of the working group is to create recommendations for field-wide standards in methods, analysis, and reporting of spoken discourse outcomes, as has been done across other related disciplines (e.g., Consolidated Standards of Reporting Trials, Enhancing the Quality and Transparency of Health Research, Committee on Best Practice in Data Analysis and Sharing). Additionally, the creation of a database through our multisite collaboration will allow the identification of psychometrically sound outcome measures and norms that can be used by clinicians and researchers to assess spoken discourse abilities in aphasia.

Development of a measure of function word use in narrative discourse: core lexicon analysis in aphasia

BACKGROUND

Although discourse-level assessments contribute to predicting real-world performance in persons with aphasia (PWA), the use of discourse measures is uncommon in clinical settings due to resource-heavy procedures. Moreover, assessing function word use in discourse requires the arduous procedure of defining grammatical categories for each word in language transcripts.

AIMS

The purpose of this exploratory study was twofold: (1) to develop core function word lists as a clinician-friendly means of evaluating function word use in discourse; and (2) to examine the ability of the core function word measure to differentiate PWA from cognitively healthy adults and persons with fluent aphasia from non-fluent aphasia.

METHODS & PROCEDURES

The 25 most commonly used function words (core function words) were extracted from narrative language samples from 470 cognitively healthy adults, which were divided into seven age groups (20s, 30s, 40s, 50s, 60s, 70s and 80s). The percent agreement of core function words for 11 PWA (fluent aphasia = 5; non-fluent aphasia = 6) and 11 age- and education-matched controls were then calculated. Percent agreement for the core function words produced was compared between the controls and the PWA group, and between participants with fluent aphasia and non-fluent aphasia.

OUTCOMES & RESULTS

The results indicated that PWA produced fewer core function words from the lists than the control group, and that core function word use was strongly correlated with aphasia severity. Persons with non-fluent aphasia produced fewer core function words than those with fluent aphasia, although this could be a confound of aphasia classification from the use of the Western Aphasia Battery (WAB)-Revised.

CONCLUSIONS & IMPLICATIONS

Core function word lists consisting of a limited number of items for quantifying function word use in discourse remain in a nascent stage of development. However, the findings are consistent with previous studies analysing the total production of function words in language samples produced by PWA. Therefore, core function words may potentially serve as a clinician-friendly manner of quantifying function words produced in discourse. What this paper adds What is already known on the subject Function word analysis in discourse requires arduous processes of identifying the error production and grammatical category of function words in discourse. Previous studies have demonstrated that core lexicon measures are an efficient, simple means of quantifying discourse in PWA. However, function words have never been considered for generating an independent core lexicon list. What this paper adds to existing knowledge As an exploratory study, we focused primarily on developing a clinician-friendly measure to evaluate function word production in discourse, motivated by the idea of an adaptation strategy within the core lexicon framework. Our findings demonstrated that by using a simple scoring system that the core lexicon measure provides, we differentiated the control group from the PWA group, and persons with fluent aphasia from persons with non-fluent aphasia. Additionally, we found significant correlations between function word production and aphasia severity determined by WAB Aphasia Quotient (AQ). What are the potential or actual clinical implications of this work? The results add empirical evidence for the utility of core function word lists for quantifying function word usage in discourse in PWA. Counting the presence and absence of function words in discourse will allow clinicians to avoid labour-intensive preparatory work, and to obtain useful diagnostic information in a less time-consuming way.

Development of Computer-Aided Semi-Automatic Diagnosis System for Chronic Post-Stroke Aphasia Classification with Temporal and Parietal Lesions: A Pilot Study

Survivors of either a hemorrhagic or ischemic stroke tend to acquire aphasia and experience spontaneous recovery during the first six months. Nevertheless, a considerable number of patients sustain aphasia and require speech and language therapy to overcome the difficulties. As a preliminary study, this article aims to distinguish aphasia caused from a temporoparietal lesion. Typically, temporal and parietal lesions cause Wernicke’s aphasia and Anomic aphasia. Differential diagnosis between Anomic and Wernicke’s has become controversial and subjective due to the close resemblance of Wernicke’s to Anomic aphasia when recovering. Hence, this article proposes a clinical diagnosis system that incorporates normal coupling between the acoustic frequencies of speech signals and the language ability of temporoparietal aphasias to delineate classification boundary lines. The proposed inspection system is a hybrid scheme consisting of automated components, such as confrontation naming, repetition, and a manual component, such as comprehension. The study was conducted involving 30 participants clinically diagnosed with temporoparietal aphasias after a stroke and 30 participants who had experienced a stroke without aphasia. The plausibility of accurate classification of Wernicke’s and Anomic aphasia was confirmed using the distinctive acoustic frequency profiles of selected controls. Accuracy of the proposed system and algorithm was confirmed by comparing the obtained diagnosis with the conventional manual diagnosis. Though this preliminary work distinguishes between Anomic and Wernicke’s aphasia, we can claim that the developed algorithm-based inspection model could be a worthwhile solution towards objective classification of other aphasia types.

Concurrent Validity and Reliability of the Core Lexicon Measure as a Measure of Word Retrieval Ability in Aphasia Narratives

Purpose General agreement exists in the literature that clinicians struggle with quantifying discourse-level performance in clinical settings. Core lexicon analysis has gained recent attention as an alternative tool that may address difficulties that clinicians face. Although previous studies have demonstrated that core lexicon measures are an efficient means of assessing discourse in persons with aphasia (PWAs), the psychometric properties of core lexicon measures have yet to be investigated. The purpose of this study was (a) to examine the concurrent validity by using microlinguistic and macrolinguistic measures and (b) to demonstrate interrater reliability without transcription by raters with minimal training. Method Eleven language samples collected from PWAs were used in this study. Concurrent validity was assessed by correlating performance on the core lexicon measure with microlinguistic and macrolinguistic measures. For interrater reliability, 4 raters used the core lexicon checklists to score audio-recorded discourse samples from 10 PWAs. Results The core lexicon measures significantly correlated with microlinguistic and macrolinguistic measures. Acceptable interrater reliability was obtained among the 4 raters. Conclusions Core lexicon analysis is potentially useful for measuring word retrieval impairments at the discourse level. It may also be a feasible solution because it reduces the amount of preparatory work for discourse assessment.