Semantic Markers in the Diagnosis of Neurodegenerative Dementias

Background: The search for early cognitive markers of Alzheimer's disease (AD) has focused on episodic memory and spatiotemporal orientation. However, recent research suggests that semantic memory is also impaired in the preclinical stages of AD. Methods: Age- and education-matched groups of participants with AD, mild cognitive impairment, and subjective memory complaints and healthy controls were assessed with 16 cognitive tests encompassing attention, orientation, episodic and semantic memory, and language tasks. Results: The battery correctly distinguished AD patients from healthy seniors in 92% of the cases. Three semantic memory-based tasks turned out to be particularly powerful for this purpose. Conclusion: Our results suggest that semantic memory tasks should be included in the battery of tests for the evaluation of cognitively impaired patients. Copyright (C) 2009 S. Karger AG, Basel