10 December 2010


Antonio Damasio. Self Comes to Mind: Constructing the Conscious Brain. William Heineman, 2010.

Oliver Sacks. In the Mind's Eye. Picador, 2010.

Damasio's book is an important and impressive study of the rise of consciousness, and while much of it is of a more technical nature than I am competent to comment on, I want to draw attention to the main theme, consciousness as a product of the brain's interaction with the body.
If I understand it rightly, Damasio argues that the beginnings of consciousness arise out of the brain's monitoring of the body. Heat and cold, light and pain, and pleasure, hunger, desire and satiation are the first contents of protoconsciouness. Thus consciousness could never arise except through biological evolution and its totally rooted in the embodied brain. 

Consciousness is generally assumed to be the product of the cerebral cortex, but Damasio argues, based on part on his study of people born with hydranencephaly, in which the cortex was destroyed before birth, that at least primitive forms of consciousness exist within the brain stem. This protoconsciouness is therefore very old.

We can see that this view of biologically routed consciousness is very different from that proposed by many in the fields of the paranormal, in which it is often radically excised from the natural world, and related not to biological 'wetware', but to vaguely defined 'fields' etc.

If Damasio is right then not only is the notion of 'survival of bodily death' meaningless, but all attempts to construct conscious computers or download human consciousness into them are doomed to failure.

Oliver Sacks, who has compiled previous accounts of unusual neurological conditions, such as The Man Who Mistook His Wife for a Hat and An Anthropologist on Mars here presents further case studies. In this anthology there is a particular emphasis on the various pathologies of sight, including Sacks' own experiences with melanoma of the eye.

The case studies range across a number of experiences such as word blindness, in which people can simply stop being able to make out letters, to prosopagnia, the inability to recognise faces, and at the other level, the persistence of powerful visual imagery in the blind. These experiences all indicate how much our visual and other sensory worlds are built up by the brain.

Studies like these at least suggest that perceptual anomalies may lie behind many of the anomalous experiences which are recounted in the Fortean and parapsychological literature. -- Reviewed by Peter Rogerson.

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