Wednesday 19th October 2016
Ground Floor Seminar Room
25 Howland Street, London, W1T 4JG
Linking memories across time via neuronal and dendritic overlaps in model neurons with active dendrites
Institute of Molecular Biology & Biotechnology (IMBB), FORTH, Heraklion, Greece
Memories are believed to be stored in distributed neuronal assemblies through activity-induced changes in synaptic and intrinsic properties. However, the specific mechanisms by which different memories become associated or linked remain a mystery. In this project, we develop a simplified, biophysically inspired network model that incorporates multiple plasticity processes and explains linking of information at three different levels: (a) learning of a single associative memory (b) rescuing of a weak memory when paired with a strong one and (c) linking of multiple memories across time. By dissecting synaptic from intrinsic plasticity and neuron-wide from dendritically restricted protein capture, the model reveals a simple, unifying principle: Linked memories share synaptic clusters within the dendrites of overlapping populations of neurons. Τhe model generates numerous experimentally testable predictions regarding the cellular and sub-cellular properties of memory engrams as well as their spatio-temporal interactions.
1. Kastellakis G., Silva, A.J. and Poirazi. P. Linking memories across time via neuronal and dendritic overlaps in model neurons with active dendrites (accepted), Cell Reports, Sept. 2016.
2. Kastelakis G., Cai, D, Mednick, S., Silva A.J and Poirazi P., Synaptic clustering within dendrites: an emerging theory of memory formation. Progress in Neurobiology, 126, 19-35, March 2015. doi: 10.106/j.pneurobio.2014.12.002
Panayiota Poirazi is a Director of Research at the Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas (FORTH) and head of the Computational Biology Laboratory. She received the B.S. in Mathematics from the University of Cyprus in May 1996, the M.S. degree in Biomedical Engineering in May 1998 and the Ph.D. degree in Biomedical Engineering in July 2000, both from the University of Southern California. Her work focuses on developing computational models of biological systems with an emphasis on the brain. She is particularly interested in modelling learning and memory functions and dysfunctions at the single cell, microcircuit and network levels. She has received several awards for academic excellence, including the EMBO Young Investigator award in 2005, two Marie Curie fellowships (2002 and 2008), an ERC Starting Grant in 2012 and the “Manolis Christofides” Young Cypriot Investigator award in 2013. She was selected as a Young Scientist by the WEF in 2014 and 2015. She is a member of AcademiaNet: a European portal for outstanding women scientists, the Young Academy of Europe and Chair of the FENS-KAVLI Network of excellence.