Olfactory and Visuospatial Learning and MemoryPerformance in Two Strains of Alzheimer’s DiseaseModel Mice—A Longitudinal Study

• Published in: PloS one 2011, Vol.6 (5), p.e19567
• Main Authors: Phillips, Matthew, Boman, Erik, Österman, Hanna, Willhite, David, Laska, Matthias
• Format: Article
• Language: English
• Subjects: NATURAL SCIENCES; NATURVETENSKAP
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0019567

Using a longitudinal study design, two strains of Alzheimer’s disease (AD) model mice, one expressing b-amyloid plaquesand one expressing Tau protein-associated neurofibrillary tangles were assessed for olfactory and visuospatial learning andmemory and their performance compared to that of age-matched controls. No significant difference between AD andcontrol mice was found in the initial set of olfactory tasks performed at 6 months of age whereas both strains of AD miceperformed significantly poorer than the controls in visuospatial learning at this age. Subsequent tests performed on thesame individual animals at 7, 8, 9, 11, 13, 15, and 18 months of age also failed to find systematic differences in olfactoryperformance between AD and control mice. In contrast, the AD mice performed consistently poorer than the controls invisuospatial re-learning tests performed at these ages. With most olfactory tasks, both AD and control mice displayed amarked decrease in performance between testing at 15 and 18 months of age. These results show that the two strains of ADmodel mice do not display an olfactory impairment in a time course consistent with human AD, but are impaired invisuospatial capabilities. The marked age-related changes observed with the olfactory tasks in both AD and control micesuggest that the observed lack of an AD-related olfactory impairment is not due to an insensitivity of the tests employed.Rather, they suggest that the olfactory system of the two AD mouse model strains may be surprisingly robust against ADtypicalneuropathologies.