"The mind is what the brain does," according to Steven Pinker, Harvard's celebrity neuropsychologist. We "are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules," according to the co-discoverer and Nobel laureate Francis Crick. "You are your synapses," according to neuroscientist Joseph LeDoux.

Neuro-reductionism, the theory that we essentially are our brains, is the flavour of the week in popular science. Which makes it all the more surprising that the hottest article in the latest issue of the journal Bioethics runs under the headline "Our Brains Are Not Us". Normally in the vanguard of attacks on the reduction of personality to a computer-like neural network are non-materialist philosophers. But this study, by Walter Glannon, of the University of Calgary, takes a different tack, something he calls "the distributed model of the mind". "I challenge and reject neuro-reductionism by arguing that the mind emerges from and is shaped by interaction among the brain, body, and environment. The mind is not located in the brain but is distributed among these three entities as the organism engages with and constructs meaning from its surroundings."

Glannon points out that although cognitive neuroscientists reject a dualist model of a non-material mind and a material body, they fall into an equally contentious theory -- brain-body dualism. This fails to appreciate the effect of the body on the brain.

The mind is not a disembodied brain in a vat of chemicals, as in some B-grade horror films, he says. Transplanting a brain into a different body would not preserve the identity of the person. In the words of German neuro-philosopher Thomas Fuchs, "The brain is only an organ, and it is not the brain, but the organism or the living person that has conscious access to the world."

Glannon's article is a reminder that neuro-reductionism has still not swept all opposition aside. Some leading neuroscientists, notably Antonio Damasio, of the University of Southern California, believe that the mind cannot be reduced to neuronal processes. ~ Bioethics, June