Dia: Dimecres, 22 de maig de 2019
Lloc: Aula T2 (2n pis), Facultat de Matemàtiques i Informàtica, UB.
A càrrec de: Alberto Pérez-Cervera, Universitat Politècnica de Catalunya
Títol: On the role of Oscillatory Dynamics in Neural Communication
Resum: Oscillations are an ubiquitous phenomena in biology but also in a wide set of complex systems, ranging from ecosystems to cells. Brain is a particularly interesting example merging oscillations and function. Fast oscillations in the brain are thought to be caused by the interaction of excitatory (E) and inhibitory (I) neurons. The rhythmic alternation of excitation and inhibition generates rhythmic changes in the excitability of the cycle, so the effect of a given input into the cycle shows a phase dependency. Indeed, inputs arriving when excitation is ready to fire (most excitable phase) are expected to generate a noticeable effect whereas inputs arriving during the inhibitory phase may be suppressed. This phase dependence for the effect of an input has been proposed as a feasible mechanism underlying neural communication. To gain insight about this communication channel, we take a rate model describing the mean activity of a E-I network, we set parameters for the model to show oscillations, and then we perturb it to study how the different phase excitability properties of the cycle shape the perturbed dynamics. The different cases that we show generate very rich dynamics (including bistability between different oscillatory states) whose implications in neural communication are discussed. To conclude, this work aims to show a set of techniques whose applicability is not reduced to neuroscience but to any complex system, provided it can be modelled by a reduced set of ODEs.
Last updated: Fri May 17 16:03:04 2019