Dendritic spines and ageing

This is a 3 year project funded (~£650K) as a collaboration between Kings College London (Prof K.P.Giese and Prof M.G. Stewart of the OU). The animal research will be carried out at Kings and the analyses at the OU. In summary the project will involve investigation of memory in ageing, based upon the fact that In old age memory abilities decline. This is primarily due to hippocampal dysfunction impairing spatial and contextual learning and memory The ageing process impacts on the physiology of hippocampal neurons, resulting in a deficit in the induction of long-term potentiation [LTP], the prime mechanism underlying memory formation However, despite LTP impairment new memories can be formed in old age. Currently, the ‘alternate mechanism’ that enables memory formation in old age is unknown. The engagement of this alternate mechanism might require more training trials and it might impair the flexibility of newly acquired memory. Based on our recently published collaboration (PNAS 2011 108(45):18471-5) we propose the hypothesis that generation of multi-innervated dendritic spines (MIS), a specific type of synapse where a dendritic spines receives more than one presynaptic input, is the mechanism of hippocampal memory formation in old age and that the engagement of this mechanism not only requires more training trials but that it also impairs the updating of newly acquired memories.