Category Archives: Plectics

Jack Cowan at MIT

Second in today’s “e-mails from Eric” department is this announcement of a talk by Jack Cowan, a mathematics professor at U. Chicago. The talk, scheduled for 16:00 on Tuesday, 3 April in room 46-3189, is abstracted as follows:

We have recently found a way to describe large-scale neural activity in terms of non-equilibrium statistical mechanics [Buice & Cowan, in preparation]. This allows us to calculate (perturbatively) the effects of fluctuations and correlations on neural activity. Major results of this formulation include a role for critical branching, and the demonstration that there exist non-equilibrium phase transitions in neocortical activity, which are in the same universality class as directed percolation. This result leads to explanations for the origin of many of the scaling laws found in LFP, EEG, fMRI, and in ISI distributions, and provides a possible explanation for the origin of alpha, beta, gamma, delta and theta waves. It also leads to ways of calculating how correlations can affect neocortical activity, and therefore provides a new tool for investigating the connections between neural dynamics, cognition and behavior.

I suspect I’ve already seen some of these results, in the video “Spontaneous pattern formation in large scale brain activity: what visual migraines and hallucinations tell us about the brain” (2006). The one review of that video is, depressingly enough, a muddled remark about “observers” in quantum mechanics and what they must mean for consciousness (and you’ll probably catch me ranting about that, anon). Fortunately, the video itself is much more informative.

For a quick primer, see “Hallucinatory neurophysics” at Sean Carroll‘s old blog, Preposterous Universe.

UPDATE (11 June 2007): Yes, I ranted more about the “quantum mind.” See here and here.