Spring 2016
Seminars are held at 11:30AM in Cullimore Hall, Room 611, unless noted otherwise. For questions about the seminar schedule, please contact Casey Diekman.
Date: May 3, 2016
Speaker: Calvin Zhang
Courant Institute of Mathematical Sciences,
New York University
Title: "A Benefit of Randomness in Synaptic Vesicle Release"
Abstract:
Neurotransmitter is released in discrete packets known as quanta, each of which is the content of one synaptic vesicle. We consider a mathematical model in which synaptic vesicles dock on the membrane of the presynaptic terminal between action potentials according to a Poisson process, and then, when an action potential arrives, each docked vesicle has a probability p_0 of releasing its content of neurotransmitter into the synaptic cleft. For this simple model, we study the effect of the parameter p_0 on the ability of the synapse to transmit signals. Surprisingly, performance improves as p_0 decreases. This is because of a compensating increase in the number of docked vesicles as p_0 decreases. When the possibility of undocking and/or finite docking sites is considered, we find instead that there is an optimal (nonzero but small, if the undocking rate is small) p_0.
*Joint work with Charles S. Peskin.