Poster session: THY-Tau22 mice show facilitated extinction learning in a hippocampus-dependent learning task

Alzheimer’s disease is characterized by two major hallmarks, namely extracellular amyloid plaques and intracellular tangles of paired helical filaments containing hyperphosphorylated tau. Besides hippocampus-dependent learning deficits, other tauopathy models showed facilitated extinction of conditioned taste aversion that were attributed to the presence of hyperphosphorylated tau in prefrontal cortex, a brain region critical for extinction. In this study, we overtrained THY-Tau22 male transgenic mice and wild types in a hippocampus-dependent task, the Morris water maze, and thereafter performed extinction sessions. Both transgenic mice and wild types developed a preference for the target quadrant as a result of acquisition training, but during extinction sessions THY-Tau22 transgenic mice showed facilitated extinction of the learned spatial preference. This facilitated extinction learning observed in a spatial task is consistent with previous animal and human studies. However, this phenomenon could be due to either effects on extinction proper, or to weaker consolidation of the platform position in transgenic mice during the acquisition phase of the task. More specific behavioural protocols will be included to decide between these two possibilities.status: publishe