Thursday was a half day here at the “Toward a Science of Consciousness” conference. We had four plenary sessions in the morning, then most of the participants went off on a trip in the afternoon. I went back to the hotel to nurse my cold and catch up on reading.

The morning lectures were all neuroscience: good meaty material from folk who spend their working days in labs, twiddling controls, peering at dials, running graphing and stats programs, that sort of thing. First up was Bernard Baars of the San Diego Neuroscience Institute on “Is Consciousness Local or Global?” What this means is: Is the faculty of conscious awareness located at some particular point(s) of the brain, or smeared across the whole structure? His answer: Both. This takes some understanding, especially if you haven’t, as Baars has (he is a big name in his field) spent thirty years up to your elbows in this stuff. The key phrase here is “Global Workspace Theory,” roughly speaking a theory about how processing of sensory data can trigger conscious activity, which may fire off chains of unconscious activity, which may in turn fire back more conscious processes, and so on. The experimental key is to compare the conscious with the unconscious processes. Baars brought it nicely together with some “theater of consciousness” analogies, the “bright spot on stage” being the focus of conscious attention, while stage hands move around behind the scenes, bells go off in dressing rooms, and the audience laughs or yawns.

Then Nao Tsuchiya from Caltech described some experiments on monkey perception. Nao has some very well-designed experiments from which he can deduce what his monkeys are seeing from the firing patterns of as few as eight individual neurons across 0.1 seconds. Interesting stuff, though I didn’t quite get the connection to reflective consciousness.

Then the Simpson’s Neuron. Neurobiologist Rafael Malach of the Weizmann Institute talked about why a particular neuron responds to certain particular stimuli but not others. His show-stopper was a screen on which he flashed brief, random video clips in quick succession with, along the bottom, a synchronous trace of the activity in one particular neuron belonging to a subject watching the stream of clips. The neuron was pretty much idle until a cip of The Simpsons came on, when it went into a rapid burst of firing. The Simpsons neuron! There was a follow-up of the subject’s voice, in a later interview, being asked to recall as many of the video clips as she could. Again, not much activity in the neuron till she mentioned The Simpsons, then YA-DA-DA-DA- … Neat stuff. I guess I’m missing the Simpson’s neuron – never could sit through that show.

[I note in passing that I have never been to an academic math/science conference that didn’t include at least one major address from one of the big Israeli research institutes. Nor have I ever been to a conference that did include an address from anywhere in the Muslim Middle East. Just mentioning it.]

Finally a long and deep address by Wolf Singer of the Frankfurt Institute of Advanced Study, concentrating on the global aspect of consciousness and its correlates in the waves of electrical activity that surge back and forth through the brain when it’s conscious. That’s a gross oversimplification, but these are really deep experimental and theoretical waters. Singer is another superstar in the field, gave a well-organized lecture and zapped right back at all the follow-up questions afterwards. Only problem for me was that his steady, monotone delivery in good but heavily-accented Dr. Strangelove English had a hypnotic effect on me, so that several times I found myself … losing consciousness. Well, I guess this is the right place to lose it. Someone’s sure to find it and return it to you.

I took time off from reading and cold-nursing in the afternoon to drive down to Nogales (it’s about an hour from Tucson) to take a look at the Mexican border. Was surprised at the density of Border Patrol vehicles and agents — they’re everywhere. Coming back on Route 82, I passed through a BP roadblock about ten miles from the border, agents checking every vehicle. On the other hand, the border fence itself — it goes right through the town, with houses on both sides only a dirt-track-width away from it — is unimpressive. Some pretty simple equipment would get you and a dozen compadres over the thing in a jiffy, if the BP weren’t around. Nogales otherwise a dull place, with an extraordinarily high proportion of seriously overweight citizens. Residents, whatever.