Single Word Comprehension Research Articles

Clinical and Linguistic Profiles and Challenges in Diagnosis of Primary Progressive Aphasia in Medan, Indonesia: A Hospital-based Study

Background Primary Progressive Aphasia (PPA) is a degenerative condition characterized by progressive loss of language function. Studies on PPA patients in Indonesia are still limited, and none has reported clinical and linguistic profiles of PPA patients who speak Bahasa Indonesia. This study aimed to describe clinical and linguistic profiles and challenges in the diagnosis of PPA patients from referral hospitals in Medan, Indonesia. Methods We retrospectively reviewed the clinical records of patients diagnosed with PPA based on the 2011 diagnostic criteria during the 2022-2023 period and described clinical characteristics data and linguistic profiles using descriptive analysis. Results We included 6 cases that fulfilled the diagnostic criteria for PPA. There were 3 cases categorized as nfvPPA, 1 case as svPPA, and 2 cases as lvPPA. There was female predominance (83.3%) and the mean age at onset was 59±2.96 years. The first symptom reported in the nfvPPA group was effortful, non-fluent speech; in svPPA, it was impaired naming and single word comprehension, while in lvPPA, it was impairment in word retrieval. Challenges in diagnosis included the availability of a standardized language tool aimed specifically for PPA in Bahasa Indonesia and the expertise needed to make such a diagnosis. Conclusion The main clinical features of the PPA reported were similar to previous findings with specific characteristics of Bahasa Indonesia. Determining language profiles of each variant of PPA in Bahasa Indonesia is crucial to establishing a correct diagnosis. Language assessment tool in Bahasa Indonesia is urgently needed to facilitate better assessment and management planning to improve quality of life.

A Meta-Analysis of Anomia Treatment in Bilingual Aphasia: Within- and Cross-Language Generalization and Predictors of the Treatment Outcomes.

The present meta-analysis investigated the efficacy of anomia treatment in bilingual and multilingual persons with aphasia (BPWAs) by assessing the magnitudes of six anomia treatment outcomes. Three of the treatment outcomes pertained to the "trained language": improvement of trained words (treatment effect [TE]), within-language generalization of semantically related untrained words (WLG-Related), and within-language generalization of unrelated words (WLG-Unrelated). Three treatment outcomes were for the "untrained language": improvement of translations of the trained words (cross-language generalization of trained words [CLG-Tx]), cross-language generalization of semantically related untrained words (CLG-Related), and cross-language generalization of unrelated untrained words (CLG-Unrelated). This study also examined participant- and treatment-related predictors of these treatment outcomes. This study is registered in the International Prospective Register of Systematic Reviews (PROSPERO) under the number CRD42023418147. Nine electronic databases were searched to identify word retrieval treatment studies of poststroke BPWAs of at least 6 months postonset. Pre- and posttreatment single-word naming scores were extracted for each eligible participant and used to calculate effect sizes (within-case Cohen's d) of the six treatment outcomes. Random-effects meta-analyses were conducted to assess weighted mean effect sizes of the treatment outcomes across studies. Multiple linear regression analyses were used to examine the effects of participant-related variables (pretreatment single-word naming and comprehension representing poststroke lexical processing abilities) and treatment-related variables (type, language, and duration). The methodological quality of eligible studies and the risk of bias in this meta-analysis were assessed. A total of 17 published studies with 39 BPWAs were included in the meta-analysis. The methodological quality of the included studies ranged from fair (n = 4) to good (n = 13). Anomia treatment produced a medium effect size for TE (M = 8.36) and marginally small effect sizes for WLG-Related (M = 1.63), WLG-Unrelated (M = 0.68), and CLG-Tx (M = 1.56). Effect sizes were nonsignificant for CLG-Related and CLG-Unrelated. TE was significantly larger than the other five types of treatment outcomes. TE and WLG-Related effect sizes were larger for BPWAs with milder comprehension or naming impairments and for treatments of longer duration. WLG-Unrelated was larger when BPWAs received phonological treatment than semantic and mixed treatments. The overall risk of bias in the meta-analysis was low with a potential risk of bias present in the study identification process. Current anomia treatment practices for bilingual speakers are efficacious in improving trained items but produce marginally small within-language generalization and cross-language generalization to translations of the trained items. These results highlight the need to provide treatment in each language of BPWAs and/or investigate other approaches to promote cross-language generalization. Furthermore, anomia treatment outcomes are influenced by BPWAs' poststroke single-word naming and comprehension abilities as well as treatment duration and the provision of phonological treatment. https://doi.org/10.23641/asha.25595712.

Exploring predictors of aphasia recovery: A 6-month follow-up study in Bengali-speaking stroke patients using the Western Aphasia Battery

This study investigated the recovery of language dysfunction in 50 consecutive stroke patients over a 6-month period, employing the Bengali adaptation of the Western Aphasia Battery (B-WAB) for language assessment. The cohort, with a mean age of 58.16 year, predominantly presented with Broca’s aphasia (36%) at the initial evaluation, and moderate aphasia was prevalent (56%). Aphasia severity was quantified using Aphasia Quotient (AQ) scores, with a mean AQ of 52.16 at the first assessment. Notably, 80% of participants exhibited ischemic strokes, and cortical stroke was the most common type (44%). Follow-up assessments revealed a statistically significant improvement in mean AQ at 6 months (63.17), with 64% demonstrating ‘some recovery,’ 8% achieving ‘complete recovery,’ and 28% exhibiting ‘no recovery.’ Improvement was most notable in single-word comprehension and repetition. Factors influencing recovery were examined, revealing that male patients experienced better recovery, and the interval between the index event and the first assessment significantly impacted outcomes. Logistic regression analysis identified AQ at first assessment and the site of stroke (cortical vs. cortico- subcortical vs. pure subcortical) as significant predictors of aphasia recovery. The study contributes valuable insights into the dynamics of aphasia recovery post-stroke, emphasizing the importance of early assessment and highlighting specific factors influencing the rehabilitation process.

CompreTAP: Feasibility and reliability of a new language comprehension mapping task via preoperative navigated transcranial magnetic stimulation

ObjectiveStimulation-based language mapping approaches that are used pre- and intraoperatively employ predominantly overt language tasks requiring sufficient language production abilities. Yet, these production-based setups are often not feasible in brain tumor patients with severe expressive aphasia. This pilot study evaluated the feasibility and reliability of a newly developed language comprehension task with preoperative navigated transcranial magnetic stimulation (nTMS). MethodsFifteen healthy subjects and six brain tumor patients with severe expressive aphasia unable to perform classic overt naming tasks underwent preoperative nTMS language mapping based on an auditory single-word Comprehension TAsk for Perioperative mapping (CompreTAP). Comprehension was probed by button-press responses to auditory stimuli, hence not requiring overt language responses. Positive comprehension areas were identified when stimulation elicited an incorrect or delayed button press. Error categories, case-wise cortical error rate distribution and inter-rater reliability between two experienced specialists were examined. ResultsOverall, the new setup showed to be feasible. Comprehension-disruptions induced by nTMS manifested in no responses, delayed or hesitant responses, searching behavior or selection of wrong target items across all patients and controls and could be performed even in patients with severe expressive aphasia. The analysis agreement between both specialists was substantial for classifying comprehension-positive and -negative sites. Extensive left-hemispheric individual cortical comprehension sites were identified for all patients. Apart from one case presenting with transient worsening of aphasic symptoms, pre-existing language deficits did not aggravate if results were used for subsequent surgical planning. ConclusionEmploying this new comprehension-based nTMS setup allowed to identify language relevant cortical sites in all healthy subjects and severely aphasic patients who were thus far precluded from classic production-based mapping. This pilot study, moreover, provides first indications that the CompreTAP mapping results may support the preservation of residual language function if used for subsequent surgical planning.

24 Individual Differences in CAMCOG-DS Performance in Children and Adults with Down's Syndrome and Relationship to Language and Reasoning

Objective:The Cambridge Cognitive Examination for Down's Syndrome (CAMCOG-DS) was developed to assess cognitive functioning and dementia-related cognitive decline in people with Down's Syndrome (DS). It has been translated into different languages and is often used in international studies. Although adapted for people with intellectual disabilities (ID), many tasks involve verbal responses and instructions are presented orally. Therefore, the administration for people with severe language deficits can be challenging. The aim of this retrospective data analysis is to examine the influence of language ability and reasoning on CAMCOG-DS performance. Study 1 examined the relationship between CAMCOG-DS, picture naming, single word comprehension and reasoning in adults with DS. Study 2 replicates and broadens the findings in a sample of children and adults with DS.Participants and Methods:Study 1 included 40 adults with DS between 18 and 51 years (M = 28.6, SD = 8.4). 25 had a mild and 15 a moderate ID. CAMCOG-DS, the short form of the Boston Naming test (BNT), a test for single word comprehension from the Werdenfelser Testbatterie (WTB) and the Colored Progressive Matrices (CPM) were administered. Study 2 included 38 participants between 8 and 59 years (23 children, M = 11.4; 15 adults; M = 31.3). 3 had a borderline, 23 a mild, and 12 a moderate ID. The same tasks as in Study 1 were applied, but the CPM was replaced by its successor, the Raven's 2.Results:In Study 1, participants with mild ID performed better in all tasks than those with moderate ID (p < .05). Moderate relationships were found between CAMCOG-DS total score and the language tasks (r = .56 and r = .46), which remained significant when level of ID was controlled for. There was also a moderate relationship between CAMCOG-DS and reasoning (r = .46). Regression analysis showed that BNT performance predicted CAMCOG-DS performance (R2 = .31). In Study 2, those with mild ID, compared to those with moderate ID, performed better in all tasks (p < .05), however, regarding the CAMCOG-DS and language tasks, this effect was larger in adults than in children. Adults performed better than children in the CAMCOG-DS and BNT (p < .05), but not in single word comprehension or reasoning. As in Study 1, moderate to large correlations were revealed between CAMCOG-DS and language tasks and between CAMCOG-DS and reasoning (r > .52), remaining significant when age and ID level were controlled for. Regression analysis showed that both naming and reasoning but not single word comprehension or age predicted CAMCOG-DS performance (R2 = .69), however, performance was best predicted by naming (R2 = .65).Conclusions:Our results suggest that language ability and reasoning relate to CAMCOG-DS performance, which is best predicted by BNT picture naming. This should be considered in CAMCOG-DS interpretation, as the capabilities of patients with lesser language ability might be underestimated. Future developments of dementia assessments for people with ID should include more nonverbal tasks.

A - 66 Non-Fluent/Agrammatic Variant of Primary Progressive Aphasia (Nappa) in a Bilingual Chinese Speaker: a Single-Case Study.

The non-fluent/agrammatic variant of primary progressive aphasia (naPPA) is a neurodegenerative syndrome associated with agrammatism in language production and effortful speech (Gorno-Tempini et al., 2011). There is limited literature on PPA in non-English speakers and few clinical cases of bilingual naPPA have been described (Tee et al., 2022; Zanini et al., 2011). Characteristics of symptoms in orthographic languages, such as Chinese, are not well understood (Ting et al., 2017). This case describes the assessment of naPPA in a bilingual Mandarin Chinese speaker. A 66-year-old Asian male with 16years of education complained of worsening aphasia in both languages over two years with initial preferential sparing of Chinese. A comprehensive neuropsychological battery was administered mostly in Chinese with select subtests in English. Language functioning was assessed with the Bilingual Aphasia Screening Test (Paradis & Libben, 1987). Agrammatism and apraxia of speech was present in both languages. Single-word comprehension and object knowledge was preserved, while comprehension of complex commands was impaired. Lexical discrimination of real and nonsense words was preserved. Delayed memory was impaired with relative improvement upon recognition. Attention, processing speed, visuospatial skills, and motor functioning were preserved. Mood was euthymic. This case revealed deficits in both languages with slower decline of the dominant language, suggesting that the less proficient language in bilinguals is more vulnerable to degeneration in naPPA.

B - 83 A Case Study of Suspected Progressive Non-Fluent Aphasia in an Older Adult with a Prior History of Seizures.

Progressive non-fluent aphasia (PNFA) is a neurodegenerative disorder characterized by agrammatism and apraxia of speech. Other features include impaired comprehension of syntactically complex structures, intact object knowledge, and spared single-word comprehension. Given the complexity of primary progressive aphasia (PPA) syndromes, neuropsychologists can play a vital role in differential diagnosis, particularly when there are comorbid medical factors. This case study presents on a 74-year-old female with progressive language and cognitive impairment over the past 8years whose care was jointly managed in specialty neurology clinics (e.g., Epilepsy and Memory Disorders) at a university medical center. She had a history of generalized convulsive seizures but with none occurring in several years. She was weaned off phenobarbital over the course of a few months to help rule out any adverse effects on functioning but her deficits persisted. Follow-up MRI showed mild-to-moderate diffuse atrophy. Her cognitive neurologist raised concerns for PPA which prompted the neuropsychological evaluation 3-4months later. Testing showed prominent impairments in fluency, naming, repetition, oral reading, and comprehension for grammatically complex questions while semantic knowledge for objects was preserved. Conversational language was halting, effortful, dysfluent, and anomic. Broader cognitive deficits were also observed during testing which was suggestive of more generalized cerebral dysfunction. The patient's profile was highly concerning for PNFA. Further work-up at the institution's Frontotemporal Dementia Clinic along with an FDG-PET scan were recommended to help further clarify her profile. Overall, this case highlights the utility of neuropsychology in the differential diagnosis of complex neurodegenerative disorders with comorbid medical factors.

Developmental trajectories of spoken language comprehension and functional communication in children with cerebral palsy: A prospective cohort study.

To investigate spoken language comprehension (SLC), single-word comprehension (SWC), functional communication development, and their determinants, in children with cerebral palsy. This was a prospective cohort study in the Netherlands spanning 2 years 6 months. The main outcomes were SLC and SWC, assessed by the Computer-Based instrument for Low motor Language Testing (C-BiLLT) and the Peabody Picture Vocabulary Test-III-NL (PPVT-III-NL) respectively; and functional communication, measured by a subscale of the Focus on the Outcomes of Communication Under Six-34 (FOCUS-34). Linear mixed models were used to determine developmental trajectories, which were compared with norm and reference data. Potential determinants, for example intellectual functions, speech production, functional communication level (classified with the Communication Function Classification System, CFCS), and functional mobility, were added to assess their effects. Children with cerebral palsy (n = 188; mean age 59 months, range 17-110) were monitored for 2 years 6 months. Developmental trajectories for SLC (C-BiLLT) and SWC (PPVT-III-NL) were nonlinear; those for functional communication (FOCUS-34) were linear. Compared with norm and reference groups, significantly delayed SLC, SWC, and functional communication development were found. Determinants for SLC and SWC were intellectual functions and functional communication level (CFCS); and for functional communication development (FOCUS-34), speech production and arm-hand functioning. Children with cerebral palsy showed delayed SLC, SWC, and functional communication development compared with norm and reference groups. Remarkably, functional mobility was not associated with the development of SLC, SWC, or functional communication. Children with cerebral palsy have delayed spoken language comprehension (SLC), single-word comprehension (SWC), and functional communication development, compared to norm and reference data. Determinants for SLC and SWC development are intellectual functions and functional communication level. Determinants for functional communication development are speech production and arm-hand functioning. Functional mobility is not associated with SLC, SWC, or functional communication.

Teaching Neuro Images : Nonfluent variant primary progressive aphasia

A 66-year-old woman presented with 4 years of progressive speech difficulty. She had nonfluent speech with phonemic errors but intact single-word comprehension and object knowledge. Her grammar was impaired in both speech and writing, and she exhibited orofacial apraxia. A clinico-radiologic (see figure) diagnosis of nonfluent variant primary progressive aphasia was made.

Word picture verification performance reveals auditory comprehension deficits in primary progressive aphasia

Word/picture verification has been found to be a sensitive measure of lexical-semantic abilities in post-stroke aphasia and reveals information about disruptions in semantic and phonological processing. Exploration of the nature of auditory comprehension deficits using word/picture verification has not been replicated in primary progressive aphasia (PPA). We tested 108 individuals with PPA [logopenic variant PPA (lvPPA), n = 50; nonfluent agrammatic PPA (nfaPPA), n = 36; semantic variant PPA (svPPA), n = 22] on a spoken word/picture verification task and a spoken word/picture matching task. The spoken word/picture matching task identified 22 (20%) of individuals as impaired, whereas the spoken word/picture verification task identified 51 (47%) of individuals as impaired (two-tailed p < 0.001). Errors on spoken word/picture verification were due to semantic rather than phonologic foils in lvPPA (nouns, p < 0.001; verbs, p < 0.001), svPPA (nouns, p < 0.001; verbs, p < 0.001), and for nouns (p = 0.001) but not verbs in nfaPPA. Spoken word/picture verification was a more sensitive measure of single-word auditory comprehension deficits in PPA than word/picture matching. The error pattern, consistent with the distributed model of semantic knowledge, suggests that degradation of semantic representations for both nouns and verbs can occur in lvPPA, which may help to distinguish lvPPA versus nfaPPA and guide treatment for anomia. • We investigated picture verification and picture matching to assess auditory comprehension impairment in primary progressive aphasia (PPA). • Picture verification was a more sensitive measure of single-word auditory comprehension deficits in PPA than picture matching. • Errors on spoken word/picture verification were due to semantic rather than phonologic foils for nouns and verbs in logopenic variant and semantic variant PPA.

Baseline structural imaging correlates of treatment outcomes in semantic variant primary progressive aphasia.

Semantic variant primary progressive aphasia (svPPA) is a neurodegenerative disorder characterized by a loss of semantic knowledge in the context of anterior temporal lobe atrophy (left>right). Core features of svPPA include anomia and single-word comprehension impairment. Despite growing evidence supporting treatment for anomia in svPPA, there is a paucity of research investigating neural mechanisms supporting treatment-induced gains and generalization to untrained items. In the current study, we examined the relation between the structural integrity of brain parenchyma (tissue inclusive of gray and white matter) at pre-treatment and treatment outcomes for trained and untrained items in a group of 19 individuals with svPPA who completed lexical retrieval treatment. Two structural neuroimaging approaches were used: an exploratory, whole-brain, voxel-wise approach and an a priori region of interest (ROI) approach. Based on previous research, bilateral temporal (inferior, middle, and superior temporal gyri), parietal (supramarginal and angular gyri), frontal (inferior and middle frontal gyri) and medial temporal (hippocampus and parahippocampal gyri) ROIs were selected from the Automated Anatomical Labeling (AAL) atlas. Analyses revealed improved naming of trained items and generalization to untrained items following treatment, providing converging evidence that individuals with svPPA can benefit from treatment for anomia. Better post-treatment naming accuracy was associated with the structural integrity of inferior parietal cortex and the hippocampus. Specifically, improved naming of trained items was related to the left supramarginal (phonological processing) and angular gyri (phonological and semantic processing), and improved naming of trained and untrained items was related to the left hippocampus (episodic, context-based memory). Future research should examine treatment outcomes in relation to pre-treatment functional and structural connectivity as well as changes in network dynamics following speech-language intervention to further elucidate the neural mechanisms underlying treatment response in svPPA and related disorders.

Language impairment in the genetic forms of behavioural variant frontotemporal dementia

BackgroundBehavioural variant fronto-temporal dementia (bvFTD) is characterised by a progressive change in personality in association with atrophy of the frontal and temporal lobes. Whilst language impairment has been described in people with bvFTD, little is currently known about the extent or type of linguistic difficulties that occur, particularly in the genetic forms.MethodsParticipants with genetic bvFTD along with healthy controls were recruited from the international multicentre Genetic FTD Initiative (GENFI). Linguistic symptoms were assessed using items from the Progressive Aphasia Severity Scale (PASS). Additionally, participants undertook the Boston Naming Test (BNT), modified Camel and Cactus Test (mCCT) and a category fluency test. Participants underwent a 3T volumetric T1-weighted MRI, with language network regional brain volumes measured and compared between the genetic groups and controls.Results76% of the genetic bvFTD cohort had impairment in at least one language symptom: 83% C9orf72, 80% MAPT and 56% GRN mutation carriers. All three genetic groups had significantly impaired functional communication, decreased fluency, and impaired sentence comprehension. C9orf72 mutation carriers also had significantly impaired articulation and word retrieval as well as dysgraphia whilst the MAPT mutation group also had impaired word retrieval and single word comprehension. All three groups had difficulties with naming, semantic knowledge and verbal fluency. Atrophy in key left perisylvian language regions differed between the groups, with generalised involvement in the C9orf72 group and more focal temporal and insula involvement in the other groups. Correlates of language symptoms and test scores also differed between the groups.ConclusionsLanguage deficits exist in a substantial proportion of people with familial bvFTD across all three genetic groups. Significant atrophy is seen in the dominant perisylvian language areas and correlates with language impairments within each of the genetic groups. Improved understanding of the language phenotype in the main genetic bvFTD subtypes will be helpful in future studies, particularly in clinical trials where accurate stratification and monitoring of disease progression is required.

Neuroanatomical correlates of screening for aphasia in NeuroDegeneration (SAND) battery in non-fluent/agrammatic variant of primary progressive aphasia.

Non-fluent/agrammatic variant of Primary Progressive Aphasia (avPPA) is primarily characterized by language impairment due to atrophy of the inferior frontal gyrus and the insula cortex in the dominant hemisphere. The Screening for Aphasia in NeuroDegeneration (SAND) battery has been recently proposed as a screening tool for PPA, with several tasks designed to be specific for different language features. Applying multivariate approaches to neuroimaging data and verbal fluency tasks, Aachener Aphasie Test (AAT) naming subtest and SAND data may help in elucidating the neuroanatomical correlates of language deficits in avPPA. To investigate the neuroanatomical correlates of language deficits in avPPA using verbal fluency tasks, AAT naming subtest and SAND scores as proxies of brain structural imaging abnormalities. Thirty-one avPPA patients were consecutively enrolled and underwent extensive neuropsychological assessment and MRI scan. Raw scores of verbal fluency tasks, AAT naming subtest, and SAND subtests, namely living and non-living picture naming, auditory sentence comprehension, single-word comprehension, words and non-words repetition and sentence repetition, were used as proxies to explore structural (gray matter volume) neuroanatomical correlates. We assessed univariate (voxel-based morphometry, VBM) as well as multivariate (source-based morphometry, SBM) approaches. Age, gender, educational level, and disease severity were considered nuisance variables. SAND picture naming (total, living and non-living scores) and AAT naming scores showed a direct correlation with the left temporal network derived from SBM. At univariate analysis, the left middle temporal gyrus was directly correlated with SAND picture naming (total and non-living scores) and AAT naming score. When words and non-words repetition (total score) was considered, a direct correlation with the left temporal network (SBM) and with the left fusiform gyrus (VBM) was also evident. Naming impairments that characterize avPPA are related to specific network-based involvement of the left temporal network, potentially expanding our knowledge on the neuroanatomical basis of this neurodegenerative condition.

What does a receptive bilingual understand? Evidence from Polish as a heritage language in Germany

Summary Our study explores the field of receptive bilingualism, a highly common phenomenon with respect to heritage languages—one that, despite its commonness, has been analyzed by few studies. We collected data from 10 receptive bilinguals of Polish as a heritage language in Germany, including data from interviews regarding language biographies, a battery of tests on language comprehension skills, and a single-word production task. The main focus of our study was the analysis of the receptive abilities of our 10 participants, with a specific emphasis on their level of listening comprehension of spoken text. We conducted an explorative correlation analysis with respect to the interrelation of listening comprehension with other parameters, such as single-word comprehension, sentence comprehension, single-word production, and the language choice of the participants’ parents. The results indicate that all participants coped well with spoken texts up to level B1 of the Common European Framework of Reference for Languages (CEFR). There was great variance in performance at levels B2 and C1, with some of the participants still performing very well. Their performance at levels B2 and C1 strongly correlated with the number of direct address instances in Polish by the parents during childhood and with single-word comprehension. Furthermore, the word production task generated the lowest outcomes of all tests, thus revealing a wide gap between receptive and productive abilities. Interestingly, the results of the word production task did not correlate with those pertaining to the listening comprehension of texts at levels B2 and C1. This finding underscores the fact that productive skills do not constitute a valid indicator of receptive abilities. In summary, our results demonstrate the special quality of receptive bilingualism and the need to avoid underestimating this specific status (e. g., in language classes).

Loss of speech and functional impairment in Alzheimer's disease-related primary progressive aphasia: predictive factors of decline

We aimed to identify features associated with different disease trajectories in Alzheimer's disease (AD)-related primary progressive aphasia (PPA). We considered 23 patients diagnosed with AD-related PPA. All patients underwent neuropsychological evaluation, 18F-Fluorodeoxyglucose-PET brain scan, CSF biomarkers measurement and APOE genotype analysis at baseline and underwent neurological follow-up for a mean time of 3 years. Patients who progressed to total loss of speech (TLoS+) had greater impairment in writing and higher t-tau concentration as compared to TLoS– patients. Patients who progressed to loss of functional autonomy (LoFA+) had greater impairment in single-word comprehension as compared to patients who maintained autonomy in self-care. Furthermore, 18F-FDG-PET SPM analyses revealed different brain metabolic patterns between TLoS+ and TLoS– and between LoFA+ and LoFA–. In conclusion, linguistic profile, CSF t-tau and brain metabolic pattern might be useful tools to predict progression to total loss of speech and loss of functional autonomy in AD-related PPA patients.

Semantic Working Memory Predicts Sentence Comprehension Performance: A Case Series Approach.

Sentence comprehension involves maintaining and continuously integrating linguistic information and, thus, makes demands on working memory (WM). Past research has demonstrated that semantic WM, but not phonological WM, is critical for integrating word meanings across some distance and resolving semantic interference in sentence comprehension. Here, we examined the relation between phonological and semantic WM and the comprehension of center-embedded relative clause sentences, often argued to make heavy demands on WM. Additionally, we examined the relation between phonological and semantic WM and the comprehension of transitive and dative active and passive sentences, which may also draw on WM resources depending on the number of propositions that must be maintained and the difficulty of processing passive clauses. In a large sample of individuals with aphasia (N = 56), we assessed whether comprehension performance on more complex vs. simpler active-passive or embedded relative clause sentences would be predicted by semantic but not phonological WM when controlling for single word comprehension. For performance on the active-passive comprehension task, we found that semantic WM, but not phonological WM, predicted comprehension of dative sentences when controlling for comprehension of transitive sentences. We also found that phonological WM, but not semantic WM, predicted mean comprehension for reversible active-passive sentences when controlling for trials with lexical distractors. On the relative clause comprehension task, consistent with prior results, we found that semantic WM, but not phonological WM, predicted comprehension of object relative clause sentences and relative clause sentences with a passive construction. However, both phonological WM and semantic WM predicted mean comprehension across all relative clause types for reversible trials when controlling for trials with lexical distractors. While we found evidence of semantic WM’s role in comprehension, we also observed unpredicted relations between phonological WM and comprehension in some conditions. Post-hoc analyses provided preliminary evidence that phonological WM maintains a backup phonological representation of the sentence that may be accessed when sentence comprehension processing is less efficient. Future work should investigate possible roles that phonological WM may play across sentence types.

Canonical Sentence Processing and the Inferior Frontal Cortex: Is There a Connection?

The role of left inferior frontal cortex (LIFC) in canonical sentence comprehension is controversial. Many studies have found involvement of LIFC in sentence production or complex sentence comprehension, but negative or mixed results are often found in comprehension of simple or canonical sentences. We used voxel-, region-, and connectivity-based lesion symptom mapping (VLSM, RLSM, CLSM) in left-hemisphere chronic stroke survivors to investigate canonical sentence comprehension while controlling for lexical-semantic, executive, and phonological processes. We investigated how damage and disrupted white matter connectivity of LIFC and two other language-related regions, the left anterior temporal lobe (LATL) and posterior temporal-inferior parietal area (LpT-iP), affected sentence comprehension. VLSM and RLSM revealed that LIFC damage was not associated with canonical sentence comprehension measured by a sensibility judgment task. LIFC damage was associated instead with impairments in a lexical semantic similarity judgment task with high semantic/executive demands. Damage to the LpT-iP, specifically posterior middle temporal gyrus (pMTG), predicted worse sentence comprehension after controlling for visual lexical access, semantic knowledge, and auditory-verbal short-term memory (STM), but not auditory single-word comprehension, suggesting pMTG is vital for auditory language comprehension. CLSM revealed that disruption of left-lateralized white-matter connections from LIFC to LATL and LpT-iP was associated with worse sentence comprehension, controlling for performance in tasks related to lexical access, auditory word comprehension, and auditory-verbal STM. However, the LIFC connections were accounted for by the lexical semantic similarity judgment task, which had high semantic/executive demands. This suggests that LIFC connectivity is relevant to canonical sentence comprehension when task-related semantic/executive demands are high.

Dysfunctional tissue correlates of unrelated naming errors in acute left hemisphere stroke

ABSTRACT Most naming error lesion-symptom mapping (LSM) studies have focused on semantic and/or phonological errors. Anomic individuals also produce unrelated word errors, which may be linked to semantic or modality-independent lexical deficits. To investigate the neural underpinnings of rarely-studied unrelated errors, we conducted LSM analyses in 100 individuals hospitalised with a left hemisphere stroke who completed imaging protocols and language assessments. We used least absolute shrinkage and selection operator regression to capture relationships between naming errors and dysfunctional brain tissue metrics (regional damage or hypoperfusion in vascular territories) in two groups: participants with and without impaired single-word auditory comprehension. Hypoperfusion—particularly within the parietal lobe—was an important error predictor, especially for the unimpaired group. In both groups, higher unrelated error proportions were associated with primarily ventral stream damage, the language route critical for processing meaning. Nonetheless, brain metrics implicated in unrelated errors were distinct from semantic error correlates.

Auditory Comprehension Deficits in Post-stroke Aphasia: Neurologic and Demographic Correlates of Outcome and Recovery.

Introduction: One of the most challenging symptoms of aphasia is an impairment in auditory comprehension. The inability to understand others has a direct impact on a person's quality of life and ability to benefit from treatment. Despite its importance, limited research has examined the recovery pattern of auditory comprehension and instead has focused on aphasia recovery more generally. Thus, little is known about the time frame for auditory comprehension recovery following stroke, and whether specific neurologic and demographic variables contribute to recovery and outcome.Methods: This study included 168 left hemisphere chronic stroke patients stroke patients with auditory comprehension impairments ranging from mild to severe. Univariate and multivariate lesion-symptom mapping (LSM) was used to identify brain regions associated with auditory comprehension outcomes on three different tasks: Single-word comprehension, yes/no sentence comprehension, and comprehension of sequential commands. Demographic variables (age, gender, and education) were also examined for their role in these outcomes. In a subset of patients who completed language testing at two or more time points, we also analyzed the trajectory of recovery in auditory comprehension using survival curve-based time compression.Results: LSM analyses revealed that poor single-word auditory comprehension was associated with lesions involving the left mid- to posterior middle temporal gyrus, and portions of the angular and inferior-middle occipital gyri. Poor yes/no sentence comprehension was associated almost exclusively with the left mid-posterior middle temporal gyrus. Poor comprehension of sequential commands was associated with lesions in the left posterior middle temporal gyrus. There was a small region of convergence between the three comprehension tasks, in the very posterior portion of the left middle temporal gyrus. The recovery analysis revealed that auditory comprehension scores continued to improve beyond the first year post-stroke. Higher education was associated with better outcome on all auditory comprehension tasks. Age and gender were not associated with outcome or recovery slopes.Conclusions: The current findings suggest a critical role for the posterior left middle temporal gyrus in the recovery of auditory comprehension following stroke, and that spontaneous recovery of auditory comprehension can continue well beyond the first year post-stroke.

A case series of verbal semantic processing in primary progressive aphasia: Evidence from the N400 effect

The semantic variant of primary progressive aphasia (PPA) is typically associated with a loss of semantic knowledge. Research on the semantic processing in the other clinical variants of PPA is, however, rather sparse and limited to off-line behavioural studies. This study aimed to investigate verbal semantic processing in patients with the three variants of PPA by the event-related potential technique. The presence, latency, amplitude and/or topographic distribution of the N400 effect may be helpful in the diagnosis of PPA and its clinical variants and it provides temporal information about semantic processing (disturbances) in the three variants of PPA. The N400 effect was studied by a categorical word-priming paradigm and a semantic-anomaly paradigm at sentence level in eight persons with PPA(-plus) and 30 age-matched healthy controls. The mean amplitudes and onset latencies of the N400 effect were compared between each patient and the control group by two methods that are applicable in clinical practice, namely visual inspection and Z-scores. The N400 effect elicited by the categorical-priming paradigm was only present in the two patients with the non-fluent variant of PPA. This effect was absent in the two patients with the semantic variant(-plus), two patients with the logopenic variant(-plus), one patient with the non-fluent variant-plus, and the patient with PPA not otherwise specified. The results of the N400 effect elicited by the semantic-anomaly task at the sentence level were variable, but differences in the presence, mean amplitudes, onset latencies and/or topographic distributions of the effect were found in all patients with PPA(-plus) in comparison with the control group. The results of our study showed that the evaluation of the N400 effect might have an added value in the diagnostic process of PPA in general and in the differentiation of patients with the non-fluent variant from patients with the logopenic and semantic variants. Furthermore, our results indicate the presence of difficulties with retrieving stored semantic knowledge or semantic integration of a word in the preceding context in patients with the three variants of PPA. These findings might help the speech-language pathologist in determining individualized therapy goals and indicate that it might be helpful to focus on verbal semantic processing in language therapy in patients with the three variants of PPA and not only in patients with the semantic variant. What is already known on the subject The semantic variant of PPA is characterized by an impaired object knowledge and single-word comprehension and these functions are relatively spared in the non-fluent and logopenic variants following the guidelines of Gorno-Tempini etal. (2011). Research on the semantic processing in patients with the non-fluent and logopenic variant is, however, rather sparse and limited to off-line behavioural studies. Only four group studies investigated verbal semantic processing by the N400 effect, and these studies indicate disturbances in the three variants of PPA. What this paper adds to existing knowledge Our results indicate the presence of difficulties with retrieving stored semantic knowledge or semantic integration of a word in the preceding context during a semantic-priming paradigm in patients with the semantic and logopenic variants of PPA and during a semantic-anomaly task at the sentence level in patients with the three variants of PPA. What are the potential or actual clinical implications of this work? The results of our study showed that the evaluation of the N400 effect might have an added value in the diagnostic process of PPA in general and in the differentiation of patients with the non-fluent variant from patients with the logopenic and semantic variants. The evaluation of the N400 effect might also help the speech-language pathologist in determining individualized therapy goals and indicate that it might be helpful to focus on verbal semantic processing in language therapy in patients with the three variants of PPA and not only in patients with the semantic variant.