Bill Gibson School of Mathematics & Statistics, University of Sydney Modelling non-electrical communication in the nervous system Wednesday 11th, May 14:05-14:55pm, Carslaw Building Room 373. From the time of Galvani's experiments in the late eighteenth century on the contraction of frog's legs, neurophysiology has been dominated by the paradigm of electrical activity as the basis for communication in the nervous system. Experimental and theoretical work focussed on excitable cells, particularly neurons. However, it has long been known that large numbers of non-excitable cells are also associated with the nervous system. In particular, glial cells outnumber neurons in the brain and it is now apparent that, far from just performing supportive and housekeeping tasks, they are also actively engaged in information processing and possibly even learning. Communication in these cells is manifested by waves of calcium ions that are released from internal stores and can be observed experimentally using fluorescent markers attached to the ions. It is thought that a particular class of glial cells, called astrocytes, form a vital link in the chain of events that links neural activity to increased vascular blood flow, thus underlying the interpretation of fMRI signals. This talk will outline aspects of the theoretical and computational modelling of non-electrical communication in cells that I have been involved in over the past few years, and indicate future lines of research.