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The following interview with Dr. Terrence Deacon was conducted at the studios of KCSM (PBS) Television in San Mateo, California on September 5, 2003.

"The multiple drafts model of consciousness (Dennett, 1991, 1996, 1998, Dennett and Kinsbourne, 1992) was developed as an alternative to the perennially attractive, but incoherent, model of conscious experience Dennett calls Cartesian materialism, the idea that after early unconscious processing occurs in various relatively peripheral brain structures "everything comes together" in some privileged central place in the brain-which Dennett calls the Cartesian Theater --for "presentation" to the inner self or homunculus. There is no such place in the brain, but many theories seem to presuppose that there must be something like it." (Dennet & Akins, Scholarpedia)

Neuroscientist Terence Deacon argues that the emergence of symbolic capacities unique to language were a key factor in the evolution of the human brain, and are a key to distinguishing human from animal forms of communication, ways of learning and brain s

Is bigger always better? When it comes to brain size, that has long been the prevailing theory-at least among big-brained humans. But a new analysis shows that in the course of primate evolution, brains and brawn haven't always been on the rise.

Hill et al. show that expansion of the human cortex during development involves the same brain areas that have changed the most in the evolutionary expansion from monkey to human brains. They suggest that it is beneficial for regions of recent evolutionary expansion to remain less mature at birth, perhaps to increase the influence of postnatal experience on their development.

"The human brain is an incredibly impressive information processor, even though it "works" quite a bit slower than an ordinary computer. Many researchers in artificial intelligence look to the organization of the brain as a model for building intelligent machines. Think of a sort of "analogy" between the complex webs of interconnected neurons in a brain and the densely interconnected units making up an artificial neural network (ANN), where each unit--just like a biological neuron--is capable of taking in a number of inputs and producing an output."

"One of the general characteristics that make primates unique are the larger brain sizes compared to body sizes in relation to other organism. His graph is limited in that it shows only the comparison of brain to body sizes of a tribe, within the family Hominidae, under a much larger taxonomic organization, the order Primates." (Primatology.net)

Two models of consciousness are contrasted with regard to their treatment of subjective timing. The standard Cartesian Theater model postulates a place in the brain where "it all comes together": where the discriminations in all modalities are somehow put into registration and "presented" for subjective judgment. In particular, the Cartesian Theater model implies that the temporal properties of the content-bearing events occurring within this privileged representational medium determine subjective order. The alternative, Multiple Drafts model holds that whereas the brain events that discriminate various perceptual contents are distributed in both space and time in the brain, and whereas the temporal properties of these various events are determinate, none of these temporal properties determine subjective order, since there is no single, constitutive "stream of consciousness" but rather a parallel stream of conflicting and continuously revised contents. Four puzzling phenomena that resist explanation by the standard model are analyzed: two results claimed by Libet, an apparent motion phenomenon involving color change (Kolers and von Grunau), and the "cutaneous rabbit" (Geldard and Sherrick) an illusion of evenly spaced series of "hops" produced by two or more widely spaced series of taps delivered to the skin. The unexamined assumptions that have always made the Cartesian Theater model so attractive are exposed and dismantled. The Multiple Drafts model provides a better account of the puzzling phenomena, avoiding the scientific and metaphysical extravagances of the Cartesian Theater.

"One of the great scientific challenges is to understand the design principles and origins of the human brain. New research has shed light on the evolutionary origins of the brain and how it evolved into the remarkably complex structure found in humans." Science Daily

"The most complex object yet discovered anywhere in the universe is the organ that fills the space between our ears. Although weighing only about 1300 to 1500 grams (three to four pounds), the human brain contains over 11 billion specialized nerve cells, or neurons, capable of receiving, processing, and relaying the electrochemical pulses on which all our sensations, actions, thoughts, and emotions depend.[2] But it is not the sheer number of neurons alone that is most striking about the brain, but how they are organized and interconnected. And to understand how neurons communicate with each other we first must consider their typical structure."

Deacon's position is that the evolution of human minds is mainly about the evolution of language. So for him, explaining the evolution of language (and the brain features that support it) explains much of interest about humans.

Evolutionary Origins of the Social Brain. In O. Vilarroya, & F.F i Argimon, (Eds.) Social Brain Matters: Stances on the Neurobiology of Social Cognition. Rodopi, 2007, 18: 215-222.

"Everyone wants wisdom and wealth. Nevertheless, our health often gives out before we achieve them. To lengthen our lives, and improve our minds, in the future we will need to change our our bodies and brains. To that end, we first must consider how normal Darwinian evolution brought us to where we are. Then we must imagine ways in which future replacements for worn body parts might solve most problems of failing health. We must then invent strategies to augment our brains and gain greater wisdom. Eventually we will entirely replace our brains -- using nanotechnology. Once delivered from the limitations of biology, we will be able to decide the length of our lives--with the option of immortality-- and choose among other, unimagined capabilities as well." Scientific American, Oct, 1994

Within two to three decades, our brains will have been "reverse-engineered": nanobots will give us full-immersion virtual reality and direct brain connection with the Internet. Soon after, we will vastly expand our intellect as we merge our biological brains with non-biological intelligence.

Metabolic changes responsible for the evolution of our unique cognitive abilities indicate that the brain may have been pushed to the limit of its capabilities. Research published today in BioMed Central's open access journal Genome Biology adds weight to the theory that schizophrenia is a costly by-product of human brain evolution.

"The research in the journal Nature Neuroscience by Professor Seth Grant, Head of the Genes to Cognition Programme at the Wellcome Trust Sanger Institute, suggests that it is not size alone that gives more brain power. Instead, he found that, during evolution, increasingly sophisticated molecular processing of nerve impulses - notably by providing more connections in the brain - allowed development of animals with more complex behaviours. " (Telegraph)

"Following certain kinds of brain lesions, patients report an inability to see objects, but if pressed to guess at their location they display a capacity to point at them with reasonable accuracy. The phenomenon, called "blindsight", is one of the more dramatic of a number of lines of evidence suggesting that being aware of doing something is distinguishable from doing something, that areas of the brain underlying the experience of doing at least some things are distinct from those needed to actually do those things."

"Evidence of brain evolution can be seen in various fields of biology, such as paleontology, ethology, behavioral biology, cognitive psychology, molecular biology and genetics."

Robots.net recently featured the Whole Brain Emulation Roadmap (pdf) produced by the Future of Humanity Institute at Oxford University.

A world-famous patient with a brain injury that restricts his vision can see coloured stars in his blind field - but only when stimulated with an electromagnetic coil. (28 October 2008 - New Scientist)