Andy Clark, Dave Chalmers

Wolf Singer

All photos:
Dave Chalmers
Andy Clark, Rupert Sheldrake
Christof Koch, Stuart Hameroff

Tucson 2008

Toward a Science of Consciousness
Eighth biennial "Toward a Science of Consciousness" conference
University of Arizona in Tucson, April 8-12, 2008

Blogged by John Derbyshire
National Review Online, April 9-13, 2008

Edited by Andy Ross

Wednesday, April 9

We started with a discussion of Benjamin Libet's astonishing results. He showed that neurophysiologically speaking, your intention to do something precedes the conscious decision to do it. First, Bill Banks (experimental psychologist) and Francesca Carota (neuroscientist) presented some worthy-but-dull quantitative stuff.

John Jacobson (philosopher and information scientist) described his work at creating an unbeatable rock-paper-scissors computer program, throwing out all sorts of witty and penetrating observations on free will, "folk volition" (what we rubes think volition is all about, as opposed to what it is really all about), and something called pessimistic indeterminism.

Physicist Daniel Sheehan (University of California, San Diego) gave us a physicist's account of the nature of time. Down at the quantum level, things get radically weird, we all know that. He believes brain processes partake of the weirdness.

Sheehan offered some startling experimental results that seemed to show presentiment. You show your suspect a blank screen, then you randomly display a picture, either an "emotional" one, that will evoke a strong neuro-response (such as a naked woman) or a "calm" one (a seascape). Then you quickly go back to the blank screen. You are monitoring neural reactions all the time. The "emotional" pictures produce not only a strong reaction after they are shown but also a measurably stronger reaction before being shown.

Sheehan claims he can explain this via known quantum effects, and says the explanatory power you get by bringing quantum weirdness into biology makes it worthwhile.

Susan Pockett (University of Auckland, New Zealand) doubted Libet's famous results, saying he'd made unjustifiable assumptions. She pooh-poohed Sheehan's quantum weirdness, arguing that there were less-strange explanations for the phenomena. She scoffed at the "presentiment" experiment, mocking its statistics.

Andy Clark (University of Edinburgh) gave an address on the "extended mind." This is the notion that, as he put it, "skin and skull are porous." He says a person's mind can fairly be taken to include things other than the brain. Cute anecdote: "A person asks me, 'Do you know the time?' 'Yes,' I reply ... and then I look at my watch ... So my 'I' includes my watch."

The session on "Sex and consciousness" was a let-down. Barry Komisaruk (Rutgers University) started with an interesting account of some neurophysiological experiments, then wandered off into the arm-waving zone. Sample: "If time is a fourth dimension, why can't consciousness be a fifth dimension?"

Jenny Wade told us about some research she'd done. She'd got a sample heavily loaded with middle-aged university women and asked them about their mind states during sex.

The evening sessions included a joint lecture on panpsychism. This seems to have been gaining a lot of ground with the metaphysicians recently. Very approximately, it's the notion that consciousness is just the out-cropping or concentration of a "psi field" that pervades everything. Even electrons and neutrons possess eensy-teensy little specks of consciousness, according to the panpsychists. Panpsychism seems, according to its adherents, to offer a glimmer of hope that we might resolve what they call "the hard problem of consciousness" by describing how mental events arise out of matter.

Bill Seager (University of Toronto) had some fun with words and syllogisms. Leopold Stubenberg wanted to resurrect Russell's "neutral monism" of 80 years ago. Steve Deiss (University of California, San Diego) stated that "things are interpretations of qualia." David Skrbina (University of Michigan) gave a lucid exposition of a dynamical systems theory approach to thinking without telling us anything about consciousness. Jonathan Powell (University of Reading) took us back to quantum weirdness, but at the level of neuronal microtubules.

As part of the session, we were asked to vote on a new name for panpsychism. We were offered nine choices.
— Panpsychism says either that all parts of matter involve mind or that the whole universe is an organism that has a mind.
— Hylozoism is the idea that all or some material things possess life, or that all life is inseparable from matter.
— Animism is the belief in souls, which may be present in animals, plants, and objects, as well as in people.
— Panexperientialism credits all entities with phenomenal consciousness but not necessarily with cognition.
— Panprotoexperientialism is weaker and credits entities only with latent consciousness.
— Quantum animism attributes spirit, mind, or mentality only to quantum-realm particles.
— Vitalism invokes a non-physical "élan vital" or spark of life.
— Neo-psychism is a new term we might coin to circumvent traditional panpsychism and its connotations.
— Neo-animism is similar.
I voted to keep "panpsychism."

Thursday, April 10

Thursday was a half day here at the conference. We had four plenary sessions in the morning, then most of the participants went off on a trip in the afternoon.

Bernard Baars (San Diego Neuroscience Institute) asked if consciousness is local or global. Is the faculty of conscious awareness located at some particular point(s) of the brain, or smeared across the whole structure? His answer is both. His "global workspace theory" is 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.

Nao Tsuchiya (California Institute of Technology) described some experiments on monkey perception. He can deduce what his monkeys are seeing from the firing patterns of as few as eight individual neurons across 0.1 seconds. I didn't quite get the connection to reflective consciousness.

Rafael Malach (neurobiology, Weizmann Institute, Israel) talked about why a particular neuron responds to certain particular stimuli but not others. He flashed brief, random video clips on a screen 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 clip 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. Neat stuff.

Wolf Singer (Frankfurt Institute of Advanced Study) gave a long address 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. These are really deep experimental and theoretical waters.

Friday, April 11

The first round of plenary sessions were on "First-Person Methodologies and the Richness of Consciousness." The first half tackles the question: "How can we get reliable reports from people about their private mental states?" The second half translates as: "Just how much are we consciously aware of?"

Are we richly conscious of a lot of things all the time, or are we only thiny conscious, with most of our mental life composed of vague impressions and reflections instantly forgotten? This is a historic divide among writers about consciousness. Eric Schwitzgebel (philosophy, University of California) argued this one.

Are the contents of experience poor, in the sense of being only immediate sense impressions, with second-order judgments about things like causation generated by upstream neural events, or do we perceive the whole package in a rich way? Susanna Siegel (philosophy, Harvard University) argued this one. She thinks there is an "impression of causation," and cited some experimental evidence.

Psychologist Chris Heavey (Univ. Nevada) told us about his methodology. He gives his subjects beepers that go off at random intervals through the day. Subjects report exactly what they were conscious of just before the beep.

Gestav Bernroider (University of Salzburg) and Stuart Hameroff (University of Arizona, and the main organizer of this conference) aired some speculations on quantum neurobiology. Stuart worked up a model of the brain as a quantum computer, with the tubulin protein molecules of neuron microtubules as the qubits — "Schrödinger's protein". There's a slight drawback here, which Stuart phrased as: "The brain is too warm and wet for delicate quantum-mechanical effects." He suggested some possible work-arounds.

Stuart wound up with his signature shtick taking in quantum mechanics, spacetime geometry, Penrose's work, Libet's results (quantum collapse propagating backwards in time), and a neutral-monist flavor of panpsychism, consciousness being a process embedded in fundamental spacetime architecture, "units" of reality collapsing quantumly as either matter or, in the highly particular circumstances of brain function, as mind.

Adrian Owen (University of Cambridge, UK) presented some experimental brain science on what may really be going on in "persistent vegetative states" (some awareness and speech comprehension, in at least a few cases). Daniel Langleben talked about using brain scans for lie detection. Mind reading is just over the horizon, but you'll need an expensive piece of equipment to do it.

The evening electives included a session on the evolution of consciousness. At what point in evolution did consciousness show up? How might we find out? Did it first show up as late as the Bronze Age? Were Homer's Greeks actually zombies, as Julian Jaynes suggested? Their self-descriptions of their own mental lives do seem to be different from ours of ours. Alex Gamma (University of Zürich) gave some useful reminders about the clumsy, non-optimizing, non-parsimonious, Rube Goldberg way that evolution actually works. Not every trait is an adaptation.

Saturday, April 12

Consciousness studies has a problem with its boundaries. If you're trying to get a science of consciousness going, what do you leave out? There is good rigorous stuff: brain imaging, neuroscience, experimental psychology, solid philosophy. But a topic like this is going to attract some New Age types and the sort of people whose claims get lengthily debunked in Skeptic magazine.

Rupert Sheldrake (biology, Cambridge University, UK) delivered his address from a chair, having been stabbed in the thigh by a lunatic at a different consciousness conference earlier in the week. He gave a witty presentation on dogs, "telephone telepathy," and the awareness some of us seem to have that we are being stared at from behind, even though we can't see the starer. Sheldrake has done some experiments, and showed us his results in summary.

The three following speakers all debunked Sheldrake to various degrees. Dick Bierman (University of Amsterdam) had repeated some of Sheldrake's experiments, with deeply unimpressive results. John Allen (University of Arizona) noted that to explain these odd anecdotal events by ESP is "conclusion by exclusion," a statistically very weak procedure. Steven Barker (University of Arizona) demolished Sheldrake's being-stared-at "results" with Bayesian analysis.

The second session was on "Psychedelics and Consciousness." Thomas Ray (zoology, University of Oklahoma) took us deep into neurochemistry. Receptors are protein molecules on the surface of nerve cells, and a lot of the neurotransmitters that go with them affect consciousness. Ray claims to have found what he calls a "meta-receptor," modulating the effect of other receptors. His meta-receptor turns joy into ecstasy, anger into paranoia, ordinary religious enthusiasm into the conviction that you are the Messiah. He hasn't published yet.

A New Agey presentation from a practitioner of "transpersonal psychotherapy" enthused about "a shamanistic psychedelic brew" called Ayahuasca.

The wind-up session was on the development of consciousness in babies, infants, and adolescents. These lectures were real dev-psych research, with brain scans, beepers, questionnaires and all, not mere philosophical ruminating.

Alison Gopnik (University of California, Berkeley) lectured on what it's like to be a baby. What it's it like is a flood of sensations, making it difficult to fix your attention on any particular thing. Babies are good at exogenous, "bottom up" attention, but not much good at the endogenous, "top down" variety. The "bottom" here is raw sensory input; the "top" is the executive self, the "I." Babies don't have much of an "I." Sample quotes:

"Consciousness narrows as a function of age."
"As we know more, we see less."
"Babies are designed to learn, not act. Adults are designed to act, not learn."

Sarah Akhter (University of Nevada) told us about adolescent consciousness. She'd done one of those beeper studies to probe the inner lives of adolescents. Her most alarming results were from an adolescent girl who, from her self-reporting, seemed to have no inner life at all.

I learned a new word here: "alexothymia," the inability to describe feelings in words. Academic conferences are great for your vocabulary. All in all an excellent conference, with a good broad variety of topics and some great speakers.

AR  I wish I had been there, to join in the fun. But the contents would not have surprised me, to judge by this account.