TY - JOUR
T1 - Quantifying grammatical impairments in primary progressive aphasia
T2 - Structured language tests and narrative language production
AU - Mack, Jennifer E
AU - Barbieri, Elena
AU - Weintraub, Sandra
AU - Mesulam, M. Marsel
AU - Thompson, Cynthia K.
N1 - Funding Information:
This research was supported by the National Institutes of Health: R01-DC08552 (Mesulam), P50-DC012283 (Thompson), and R01-DC01948 (Thompson). The authors would like to thank their colleagues at the Mesulam Center for Cognitive Neurology and Alzheimer's Disease and the Aphasia and Neurolinguistics Research Laboratory at Northwestern University, in particular Sarah Chandler and Benjamin Rader for assistance with data collection, management, and analysis. We also thank the research participants, their families and caregivers for their contributions to this work.
Funding Information:
This research was supported by the National Institutes of Health : R01-DC08552 (Mesulam), P50-DC012283 ( Thompson ), and R01-DC01948 ( Thompson ). The authors would like to thank their colleagues at the Mesulam Center for Cognitive Neurology and Alzheimer's Disease and the Aphasia and Neurolinguistics Research Laboratory at Northwestern University, in particular Sarah Chandler and Benjamin Rader for assistance with data collection, management, and analysis. We also thank the research participants, their families and caregivers for their contributions to this work.
Publisher Copyright:
© 2020 Elsevier Ltd
PY - 2021/1/22
Y1 - 2021/1/22
N2 - 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.
AB - 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.
KW - Language production
KW - Narrative
KW - Primary progressive aphasia
KW - Syntax
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U2 - 10.1016/j.neuropsychologia.2020.107713
DO - 10.1016/j.neuropsychologia.2020.107713
M3 - Article
C2 - 33285187
AN - SCOPUS:85097882793
VL - 151
JO - Neuropsychologia
JF - Neuropsychologia
SN - 0028-3932
M1 - 107713
ER -