The mechanisms and functional consequences of presynaptic plasticity within the hippocampus have received relatively little attention, as compared to its postsynaptic counterparts LTP and LTD. Presynaptic forms of plasticity provide a highly dynamic mechanism to act on information transfer and circuit function, at different times scales ranging from hundreds of milliseconds to days.

We examine the mechanisms by which two essential presynaptic molecular components, Syt7 and GluK2, contribute to presynaptic plasticity at identified synapses in the hippocampus. In collaboration with Valentin Nägerl, we investigate how the close interplay between presynaptic functional and structural plasticity determines the dynamics of information processing, encoding and retrieval in the CA3 region of the hippocampus, a key region for the early stages of memory acquisition, and in particular on DG-CA3 connections which constitute a major entry point from the cortex to the hippocampus.

We address the following questions: What are the subcellular mechanisms of short-term facilitation at DG-CA3 connections? What are the dynamic features and mechanisms of structural plasticity at Mf-CA3 synapses? How does presynaptic plasticity impact information transfer and local CA3 circuit function (including excitation/inhibition balance) in vivo? What consequences on brain oscillations and brain state at a single cell and neural ensemble level? Is presynaptic plasticity involved in memory encoding and retrieval?