Assessing Olfactory Learning and Memory in the 5XFAD Mouse Model of Alzheimer’s Disease

Abstract

Using an operant-olfactometer, the long term learning and memory, executive function, olfactory sensitivity, and working memory of the 5XFAD mouse model of Alzheimer’s disease was assessed. Six month old male and female 5XFAD and wildtype mice were tested. No deficits were found on an olfactory discrimination task or a reversal learning task. Female and transgenic mice performed better than male and wildtype mice on the higher odour concentrations, but not the lower concentrations, of the sensitivity task, suggesting differences in learning rate or maximum performance on the task, but not olfactory detection. This study demonstrated for the first time that mice are able to learn an olfactory delayed matching to sample task with delays up to 30 seconds long. Female mice showed higher levels of performance on the matching to sample task than male mice, indicative of better working memory.