Spike avalanches in vivo suggest a driven, slightly subcritical brain state

In self-organized critical (SOC) systems avalanche size distributions follow power-laws. Power-laws have also been observed for neural activity, and so it has been proposed that SOC underlies brain organization as well. Surprisingly, for spiking activity in vivo, evidence for SOC is still lacking. Therefore, we analyzed highly parallel spike recordings from awake rats and monkeys, anesthetized cats, and also local field potentials from humans. We compared these to spiking activity from two established critical models: the Bak-Tang-Wiesenfeld model, and a stochastic branching model. We found fundamental differences between the neural and the model activity. These differences could be overcome for both models…

• NS
  National Science Foundation
• DF
  Deutsche Forschungsgemeinschaft

  Awards: GRK 1589/1, GRK 1589, 1589/1
• BF
  Bundesministerium für Bildung und Forschung

  Awards: 01GQ1005B, 01GQ0742, GRK 1589/1