This application proposes to study individuals with Primary Progressive Aphasia (PPA), a unique neurodegenerative disease that primarily affects the language network, to identify limitations in memory performance due to aphasia by manipulating standard implicit and explicit memory paradigms. More specifically, the studies will 1) measure interference caused by semantic relatedness, 2) compare verbal and nonverbal memory performance, and 3) vary stimulus presentation order (word-to-picture or picture-to- word) priming to determine vulnerabilities in PPA patient's memory performance. Results from the studies will provide behavioral information about the influence of aphasia on memory in a model where the lesions are not as arbitrary as they are in stroke related aphasia. Currently, evidence for preserved memory in PPA comes mainly from caregivers' observations of behavior in daily life, since it is difficult to assess memory clinically due to the language dependence of most neuropsychological tests. Thus, this proposal may have translational value clinically, since it may identify differences in the aphasic patients' memory that would result in a more comprehensive clinical characterization and, ultimately, better care. [unreadable] [unreadable] [unreadable]