Poster A71, Saturday, March 24, 1:30–3:30 pm, Exhibit Hall C
Impoverished Semantic Memory in Mild Cognitive Impairment
Nathaniel Klooster1, Arun Pilania1, David A. Wolk1, Anjan Chatterjee1; 1University of Pennsylvania
Mild Cognitive Impairment (MCI) may be a useful target to identify prodromal cognitive manifestations of Alzheimer’s Disease pathology. While MCI patients may show some impairment in language abilities, semantic memory is often considered minimally affected although is often not well-tested with standard psychometric batteries. Here, we test the hypothesis that people with amnestic-MCI show evidence of semantic memory impairments. To test this hypothesis, we assessed depth and richness of semantic knowledge. The Word Associates Test (WAT) is a receptive measure of depth of vocabulary used in first and second-language learning research. Participants choose four correctly matching synonyms or collocates from among eight possibilities for each target word. The number of senses a word can take (e.g. pound: to beat down; a unit of weight; an enclosure for stray dogs; the British unit of currency) is a widely studied measure of semantic richness in psycholinguistic studies. In the Senses-listing task, participants are given one minute to list as many senses as possible for target words chosen from normed databases. MCI patients performed significantly worse on the WAT and the senses-listing task than demographically matched healthy comparison participants. Deficits on both receptive and productive measures of semantic richness and depth of vocabulary knowledge suggest that semantic memory is frequently impoverished in patients with MCI. Our ongoing work is examining the sensitivity of these experimental measures as compared to standard neuropsychological tests, and the behavioral correlations with biomarkers such as medial temporal lobe integrity and cerebral amyloid pathology.
Topic Area: LONG-TERM MEMORY: Semantic