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Progressive Nonfluent Aphasia: Language, Cognitive, and PET Measures Contrasted with Probable Alzheimer's Disease
M Grossman1, J Mickanin, K Onishi
1University of Pennsylvania School of Medicine.
Journal of Cognitive Neuroscience
|August 27, 2013
Summary
Progressive nonfluent aphasia (PNFA) primarily affects language, unlike Alzheimer's disease (AD). Specific left hemisphere cortical defects in PNFA patients correlate with distinct language and cognitive impairments.
Area of Science:
- Neurology
- Linguistics
- Neuroimaging
Background:
- Progressive nonfluent aphasia (PNFA) presents unique language and cognitive challenges.
- Differentiating PNFA from other neurodegenerative conditions like probable Alzheimer's disease (pAD) is crucial for accurate diagnosis and management.
Purpose of the Study:
- To compare the language and cognitive profiles of PNFA patients with those of pAD patients.
- To identify specific cortical defects in PNFA using positron emission tomography (PET) that correlate with observed cognitive deficits.
Main Methods:
- Longitudinal assessment of language and cognitive functions in PNFA patients.
- Direct comparison of cognitive performance between PNFA and pAD patient groups.
- Positron emission tomography (PET) imaging to analyze regional cerebral blood flow and cortical activity in PNFA patients.
Main Results:
- PNFA patients exhibited progressively telegraphic speech/writing and impaired sentence comprehension, with preserved memory and visual function.
- Compared to pAD patients, PNFA patients showed significant deficits in grammatical processing, phonemic judgment, repetition, and digit span.
- PET scans revealed reduced left hemisphere cortical activity in PNFA, with prominent defects in left superior/middle temporal and inferior frontal regions, distinct from pAD patterns.
Conclusions:
- PNFA is characterized by a distinct pattern of language and cognitive impairments.
- These impairments are associated with specific patterns of cortical dysfunction in the left hemisphere.
- The findings aid in distinguishing PNFA from pAD and understanding its underlying neurobiology.
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