Journal club presentation by M.Dehghani

Neuronal Avalanches in Neocortical Circuits

John M. Beggs and Dietmar Plenz

Link to paper



Networks of living neurons exhibit diverse patterns of activity, including oscillations, synchrony, and waves. Recent work in physics has shown yet another mode of activity in systems composed of many nonlinear units interacting locally. For example, avalanches, eartاquakes, and forest fires all propagate in systems organized into a critical state in which event sizes show no characteristic scale and are described by power laws. We hypothesized that a similar mode of activity with complex emergent properties could exist in networks of cortical neurons. We investigated this issue in mature organotypic cultures and acute slices of rat cortex by recording spontaneous local field potentials continuously using a 60 channel multielectrode array. Here, we show that propagation of spontaneous activity in cortical networks is described by equations that govern avalanches. As predicted by theory for a critical branching process, the propagation obeys
a power law with an exponent of 3/2 for event sizes, with a branching parameter close to the critical value of 1. Simulations show that a branching parameter at this value optimizes information transmission in feedforward networks, while preventing runaway network excitation. Our findings suggest that “neuronal avalanches” may be a generic property of cortical networks, and represent a mode of activity that differs profoundly from oscillatory, synchronized, or wave-like network states. In the critical state, the network may satisfy the competing demands of information transmission and network stability.

About This Event

Start date08/29/2018 10:00
End date08/29/2018 12:00



  • unnamed

    Mini-symposium Held at IUST

    In July, 2017 we held a one-day mini-symposium at IUST, for the interchange of scientific expertise and findings between different projects of the our lab and external collaborating teams. The lectures were organized in two panels: Invited talks (given by principle investigators cooperating with our lab) and Project presentations (delivered by PhD students). Topics ranging all the way from the dynamics of neural coding in primate brain to computational approaches in modeling the neural system were covered through these lectures. Importantly we had the honor to host Dr. Fatemeh Bakouie (Shahid Beheshti University), Dr. Zeinab Fazlali (IPM School of Cognitive Sciences), Prof. Dr. Shahriyar Gharibzadeh (Amirkabir University of Technology) and Dr. Marzieh Zare (IPM School of Computer Sciences), to present their ongoing research lines in the symposium.
  • 20160914_192500

    The surgery center has been launched in the Cognitive Neurobiology Lab

    We are pleased to announce that on Sep 2016, we launched a non-human primate surgery center in IPM School of Cognitive Sciences. The surgery room is equipped with the most modern equipment enabling primate neuroscientists to carry out the most sophisticated brain surgeries. These surgeries are aimed at implanting either fixation or neural implants. Facilities such as accurate human-level monitoring and anesthesia systems enable us to carry out surgeries with the highest standards of animal welfare.
  • F. Zareayan’s winning support to attend FENS 2016

    Fatemeh Zareayan won the prize to attend the 10th Forum of Neuroscience Conference to be held in Copenhagen July 2-6, 2016 from the Iranian Cognitive Sciences and Technologies Council

  • PhD defence

    "Moein Esghaei successfully defended his thesis at IPM. His thesis addressed the role of low frequency oscillatory activities of brain in the process of selective attention."