Abstract
This study examined the time course of object naming in 21 individuals with primary progressive aphasia (PPA) (8 agrammatic (PPA-G); 13 logopenic (PPA-L)) and healthy age-matched speakers (n=17) using a semantic interference paradigm with related and unrelated interfering stimuli presented at stimulus onset asynchronies (SOAs) of -1000, -500, -100 and 0. ms. Results showed semantic interference (SI) (i.e. significantly slower RTs in related compared to unrelated conditions) for all groups at -500, -100 and 0. ms, indicating timely spreading activation to semantic competitors. However, both PPA groups showed a greater magnitude of SI than normal across SOAs. The PPA-L group and six PPA-G participants also evinced SI at -1000. ms, suggesting an abnormal time course of semantic interference resolution, and concomitant left hemisphere cortical atrophy in brain regions associated with semantic processing. These subtle semantic mapping impairments in non-semantic variants of PPA may contribute to the anomia of these patients.
Original language | English (US) |
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Pages (from-to) | 237-250 |
Number of pages | 14 |
Journal | Brain and Language |
Volume | 120 |
Issue number | 3 |
DOIs | |
State | Published - Mar 2012 |
Funding
This research was supported by the NIH Grants: RO1DC01948 (C.K. Thompson), R01DC008551(M. Mesulam), and AG13854 (Alzheimer’s Disease Core Center), Northwestern University. The authors wish to thank Dr. Darin Cobia for his assistance with data analysis. We also acknowledge the Center for Advanced MRI (CAMRI) at Northwestern University for their scanning support.
Keywords
- Cortical thickness
- FreeSurfer
- Naming deficits in primary progressive aphasia
- Primary progressive aphasia
- Semantic interference
- Word interference paradigms
ASJC Scopus subject areas
- Experimental and Cognitive Psychology
- Speech and Hearing
- Cognitive Neuroscience
- Language and Linguistics
- Linguistics and Language