I'm watching it right now, for the second time, trying to follow along. We are asked to hear neurons (live cell assemblies) in a rat's brain (in its hippocampus) firing as it runs around.
An excerpt from the abstract:
"The lifetime of oscillating assemblies is internally regulated and can be accelerated by the locomotion speed of the rat and possible other gain factors. The internally generated assemblies can give rise to a perpetually changing composition of assembly membership even in the absence of environmental or idiothetic inputs. We hypothesize that the mechanisms underlying the intrinsically shifting assembly sequences is the substrate of episodic memory."