Events

ELSC Seminar: Maoz Shamir - Jan. 18th, 2018

January 18, 2018

ELSC cordially invites you to the lecture given by:

 

 

Prof. Maoz Shamir 

Zlotowski Center for Neuroscience, Ben-Gurion University 

 

On the topic of:

 

“Emergence of oscillatory activity via spike timing dependent plasticity” 

 

The lecture will be held on Thursday, January 18th, at 17:00

at ELSC: Silberman Bldg., 3rd Wing, 6th Floor,

 Edmond J. Safra Campus 

 

Light refreshments at 16:45


Abstract:                                                                                       

Neuronal oscillatory activity has been reported in relation to a wide range of cognitive processes including the encoding of external stimuli, attention, and learning. In certain cases changes in the oscillatory activity have been related to pathological states. Although the specific role of these oscillations has yet to be determined, it is clear that neuronal oscillations are abundant in the central nervous system. These observations raise the question of the origin of these oscillations: are the mechanisms responsible for generation of these oscillations and that allow the propagation of the oscillatory signal genetically hard-wired or can they be acquired via a process of learning?

In my talk I will focus on spike timing dependent plasticity (STDP), and examine under what conditions this unsupervised learning rule can enable the propagation of oscillatory activity downstream in the central nervous system.

Next we will study whether STDP can facilitate the emergence of oscillatory activity? To this end we studied the STDP dynamics in a toy-model with simplified architecture. To analyze the system it is convenient to study the phase-diagram that depicts the possible dynamical states of the network as a function of the synaptic weights. This phase diagram displays a rich repertoire of possible dynamical behaviors including regions of different fixed point solutions, bi-stability and a region in which the system exhibits oscillatory activity. STDP introduces dynamics for the synaptic weights themselves; hence, induces a flow on the phase-diagram. We derived the dynamical equations for the synaptic couplings, and studied the conditions under which the flow will converge to an oscillatory state of the neuronal network.