Wh- questions and passive sentences in non-fluent variant PPA and semantic variant PPA: Longitudinal findings of an anagram production task

Sentence Comprehension in Primary Progressive Aphasia: A Study of the Application of the Brazilian Version of the Test for the Reception of Grammar (TROG2-Br)

Sentence-comprehension deficits have been described in patients with primary progressive aphasia (PPA). However, most instruments to address this domain in more detail and in a clinical context have not been adapted and translated into several languages, posing limitations to clinical practice and cross-language research.

Objectives

The study aimed to (1) test the applicability of the Brazilian version of the Test for Reception of Grammar (TROG2-Br) to detect morphosyntactic deficits in patients with PPA; (2) investigate the association between performance in the test and sociodemographic and clinical variables (age, years of formal education, and disease duration); (3) characterize the performance of individuals presenting with the three more common variants of PPA (non-fluent, semantic, and logopenic) and mixed PPA (PPA-Mx) and analyze whether TROG-2 may assist in the distinction of these clinical profiles.

Methods

A total of 74 cognitively healthy participants and 34 individuals diagnosed with PPA were assessed with TROG2-Br. Overall scores (correct items, passed blocks), types, and categories of errors were analyzed.

Results

In controls, block scores were significantly correlated with years of formal education (Spearman's r = 0.33, p = 004) but not with age. In PPA, age, education, and disease duration were not significantly associated with performance in the test. Controls presented a significantly higher performance on TROG2-Br compared to PPA individuals and their errors pattern pointed to mild general cognitive processing difficulties (attention, working memory). PPA error types pointed to processing and morphosyntactic deficits in nonfluent or agrammatic PPA, (PPA-NF/A), logopenic PPA (PPA-L), and PPA-Mx. The semantic PPA (PPA-S) subgroup was qualitatively more similar to controls (processing difficulties and lower percentage of morphosyntactic errors). TROG2-Br presented good internal consistency and concurrent validity.

Discussion

Our results corroborate findings with TROG-2 in other populations. The performance of typical older adults with heterogeneous levels of education is discussed along with recommendations for clinical use of the test and future directions of research.

Quantifying grammatical impairments in primary progressive aphasia: Structured language tests and narrative language production

PURPOSE

This study examined grammatical production impairments in primary progressive aphasia (PPA), as measured by structured tests and narrative samples. We aimed to quantify the strength of the relationship between grammatical measures across tasks, and identify factors that condition it. Three grammatical domains were investigated: overall sentence production, verb morphology, and verb-argument structure.

METHODS

77 participants with PPA (34 PPA-G, 16 PPA-L, 15 PPA-S and 12 other) completed a battery of grammatical tests and a narrative language sample was obtained. Accuracy scores were computed for the language tests and the narrative samples were analyzed for both accuracy of selected narrative variables as well as grammatical diversity across the three grammatical domains. Principal components analysis (PCA) and multiple regression were used to examine cross-task relationships for all measures.

RESULTS

As expected on the basis of classification criteria, accuracy scores were lower for the PPA-G group as compared to the PPA-L and PPA-S participants for overall sentence production and verb morphology, but not argument structure. Grammatical accuracy in narratives strongly predicted overall language test performance in PPA-G, whereas grammatical diversity in narratives did so in PPA-L, and no significant correspondence between narrative and language test performance was found for PPA-S. For individuals with severe grammatical impairments only, error distribution for both morphology and argument structure was strongly associated in structured tasks and narratives.

CONCLUSIONS

Grammatical production in narrative language predicts accuracy elicited with structured language tests in PPA. However, unique narrative production patterns distinguish PPA by subtype: accuracy for PPA-G, and grammatical diversity for PPA-L. The impairment in PPA-G is likely to reflect a core impairment in grammar whereas that of PPA-L may be closely tied to the word retrieval and verbal working memory deficits that characterize this variant. This underscores the theoretical distinction between PPA-L and PPA-G, as well as the importance of including grammatical diversity measures in analyses of language production, especially for patients who do not display frank agrammatism. Further, the results suggest that measures of domain-specific language deficits (i.e., verb morphology vs. argument structure) are robust across tasks only in individuals with severe grammatical impairments.

Grammatical Ability Predicts Relative Action Naming Impairment in Primary Progressive Aphasia

BACKGROUND

Findings from several studies have indicated that participants with nfvPPA and participants with svPPA exhibit different patterns on action and object naming tasks, while other recent studies have found that neither participants with nfvPPA nor participants with svPPA show a significant difference in accuracy between object naming and action naming.

AIMS

The goal of this study was to test the hypothesis that relative action naming impairment is associated with grammatical ability in PPA, rather than a specific subtype of PPA.

METHODS & PROCEDURES

Thirty-four participants with PPA completed the Boston Naming Test, the Action Naming subtest of the Boston Diagnostic Aphasia Examination, and the Northwestern Anagram Test, which was used to measure grammatical ability. Z-scores for the two naming tasks were calculated based on normative data from unimpaired controls. For each participant with PPA, the relative action naming impairment was calculated by subtracting the object naming z-score from the action naming z-score. Linear regression analysis was then used to evaluate the role of grammatical ability as a predictor of relative action naming impairment, while controlling for age, education, cognitive ability (as measured by the Montreal Cognitive Assessment), and semantic ability (as measured by the Pyramids and Palm Trees test). The interaction between grammatical ability and each control variable was also examined.

OUTCOMES & RESULTS

The main effect of grammatical ability was a significant predictor of relative action naming impairment, while none of the control variables was a significant predictor. However, the interaction between grammatical ability and semantic ability was also significant.

CONCLUSIONS

Individuals who have both grammatical impairment and semantic impairment have the largest relative action naming impairment. These individuals may benefit from a treatment that focuses on the retrieval of verbs and their arguments.