sábado, 6 de dezembro de 2008

Expand Your Mind:

Getting a Grasp on Consciousness

Speakers:
Alexander Shulgin
Christof Koch
Patricia Churchland
Ira Flatow

About the Lecture

At some point, these panelists suggest, the issue of defining consciousness may just disappear. Suggests Christof Koch: “Let’s treat consciousness as an empirical problem to be tackled by the biological sciences.”

Koch makes distinctions between different kinds of consciousness: sleep and its varied stages; awareness of sounds, sights and smells; levels of arousal. All these different states are properties “of complex adaptive networks with massive feedback shaped by natural selection.” And there are many behaviors that occur without consciousness. “When we talk, we don’t know what we’re going to say,” says Koch. His research has focused on finding “neural correlates of consciousness.” In one experiment with patients whose brains were implanted with 100 electrodes, he flashed pictures of Jennifer Aniston and the Sydney Opera House. While the patients could not remember what they’d seen, neurons responded selectively to these images. Studies like this, with even more sensitive tools, may some day help develop an information-based theory of consciousness, Koch says.

Mental phenomena are nothing but phenomena of the physical brain, says Patricia Churchland. It’s “an illusion of the brain” to think that we have a “nonphysical soul that does our feeling.” But how the brain creates constructs of itself and things in the world remains a major puzzle. For instance, how does a brain “habitually represent goals, plans and projects -- things that don’t yet exist?” And what about the huge amount of spontaneous activity in the brain that occurs while we’re resting? We don’t understand how the “organization of a motor response is achieved,” nor how these responses are integrated across sensory systems together with memory. Churchland anticipates a fundamental shift in looking at the brain that will merge philosophical and neurobiological issues.

In his day, Alexander Shulgin explored consciousness through “the art of chemistry.” He synthesized a version of mescaline and invented other psychedelic drugs, experimenting on himself, before the era of government and university regulations. “Each material had to be learned, as a new meeting…. The beauty of the final results, finding out what the effects were, was that you couldn’t be wrong.” If he reported visual enhancements, and recall of memories, his data was “always a winner,” because it was mostly a matter of subjective experience. Shulgin rues the laws and propaganda against psychedelic drugs, because he believes these drugs would serve as a useful “probe to look at the function of mind.”
MIT World