Colloquium: Christopher Kello

You are invited to the following School of Informatics and Computing Colloquium.

Christopher Kello, University of California, Merced, will present, "Critical Branching Neural Computation."

Friday, September 18, 2009
3:00 p.m.
Lindley Hall, Rm. 102

Abstract:
Brain networks transmit and process information via action potentials (i.e. spikes) generated by neurons and transmitted via synapses. Spiking activity, as quantified by sums of spikes over neurons, cannot overly expand or contract over time. Stability is achieved in the balance, and can be expressed in terms of critical branching. I present a spiking neural network model with a local tuning algorithm that converges spiking dynamics to their critical branching point. The model is used as a liquid state machine to examine its computational capacity as defined by the effects of perturbations (e.g. environmental inputs) to spiking dynamics. The model exhibits maximal capacity near the critical branching point, as well as power law distributions and fluctuations in spiking activity. These power laws are observed in various measures of neural and behavioral activities, suggesting that critical branching may indicate and illustrate a general principle of cognition.