Neuronal Avalanches

It has recently been suggested that, in order to provide the richness of behavior which is seen empirically, the brain must operate in a critical regime between a phase of order and disorder [1]. In particular, such critical behavior is exhibited in what is termed neuronal avalanches. These cascades of synaptic activity have been seen both in vitro and in vivo [6]. Several models have been put forth to explain this apparently critical phenomena, ranging from simple dynamical models of neural networks to full fluctuation field theories, though the specific mechanism remains unclear. Despite the reproducibility of this behavior, its connection to high-order processes is yet unknown, though some have linked neuronal avalanches to large scale brain features such as information storage [2, 4], synaptic stability [3], even epileptic shock [1]. In hopes of providing a larger context for this pervasive neural behavior, we examine the aforementioned experimental findings and compare various theoretical models which predict them.