John McCrone

McCrone begins with two assumptions: that "self-consciousness must have a biological basis" and that the mind evolved.

Language is one of the defining human characteristics; indeed it is language that has permitted our species to learn how to control the environment around us rather than being forced to adapt to it. Language permitted self-awareness and self-consciousness.

Being intelligent is hard work. The brain uses about one fifth of the oxygen intake even though it's only about one fiftieth of the body's weight. During the climatic changes of the Miocene era some 10 million years ago, the apes which had flourished in the rich forest environment were forced to adopt a land-gait and leave the trees. Most of the ape lines became extinct, a process almost completed today; they had reached an evolutionary dead-end. Only the human line of apes survived. Because two-legged movement is not as efficient, nor as fast as four-legged, these strange upright ancestors of ours developed social organizations for the common defense (also a characteristic of the few remaining apes like baboons and chimps.) Still, this alone was not enough for several early hominid lines became extinct, unsuccessful experiments of God.

The Australopithecines, with strong jaw for chewing up the tough roots and plants of its diet disappeared with the advent of the colder ice age. Our direct ancestors, with smaller jaw, a more varied diet, and the ability to cook, were better suited to adapt to the change in environment. The last 3,000,000 years have been dominated by the ice-age with only brief 10,000 - 20,000-year long interruptions of more temperate climates (we near the end of the most recent one now.) These periods placed terrible stress on the animals that had developed warm coats and had adapted to colder climates. Many species died out. The lightweight homo line with his intelligence and flexible diet was again successful. Another advantage was food-sharing -- almost unique to humans -- and pair bonding. But language, appearing it is thought with home sapiens, was to make a crucial difference. "Language paved the way for all the special abilities that we so value abilities such as self-awareness, higher emotion and personal memories."

McCrone examines how various basic mental abilities work such as thought, memory and learning, in order to appreciate the structures that language expanded.… (mere)

John McCrone is a researcher of consciousness, publishing in journals such as New Scientist.
He follows the subject from its optimistic beginnings, through its almost disappearance at the hands of behaviourists, to the renaissance of the 1990s tied to new brain scanning techniques.

Decades spent on this subject coupled with acquaintance with the leading researchers has in my opinion produced a remarkable book. He synthesizes earlier research with new findings to produce a fundamentally new picture of how the brain reacts to (or he would say anticipates ) events.

The idea of the brain as a computer is misleading as it suggests an input/program/output model with an ever more complex program to handle new situations. Instead he supports the findings of Donald Hebb in the 1940s showing that nerve fibres make up a network rather than a system of straight lines of stimulus and response, and that there is a high level of feedback.

Brain processing is a competition rather than a calculation and networks evolve their way to stable solutions.

In other words stimuli (including internally generated thoughs), have to compete for attention and are selected or faded depending on the results that they produce. The problem is that all the effort has gone into trying to write more complicated programs for the hardware instead of trying to get it rewire itself and evolve its own processing routines.

As he says with regard to the brain/computer comparison: "Quite simply, one has circuits that are alive, and the circuits of the other are dead."
This is not to say that the system is completely fluid. The brain reaches a balance between main areas that have a firm structure that will inevitably be needed, and more plastic areas that enable adaption to the unforseen.

Analysis of information (and subsequent neural rewiring) are shown to work on a population voting system, i.e. cells representing different aspects of an experience can fire strongly, weakly, or not at all, creating a picture with shades of certainty and meaning.

Action itself is anticipated. As he says, "......the very fact that we can feel caught out, simply confirms that we must have had a set of expectations in the first place." Confirmed anticipation (for an unfamiliar task) allows its quick automation in the brains circuitry allowing future repetition with much reduced effort. University of Washington PET scans give conclusive evidence and are shown in a series of photos.

Other chapters deal with anticipation leading to a focusing of awareness and the critical role of language as an aid to symbolism and trigger for thought patterns. Try making a mental plan without words!

In my opinion this is a major book, particularly for the signposts that it holds for truly intelligent machines.… (mere)