Wednesday, May 25, 2005


The following two passages are from another great book I'm reading about the subject of consciousness. I really like his description of how we come to be selves and what constitutes "the self". The book is by Ramachandran: A BRIEF TOUR OF HUMAN CONSCIOUSNESS.


[Open quote] Mental illness might be thought of as disturbances of consciousness and of self, two words that conceal great depths of ignorance. Let me try to summarize my own view of consciousness. There are really two problems here - the problem of the subjective sensations or qualia and the problem of the self. The problem of qualia is the more difficult.

The qualia question is, how does the flux of ions in little bits of jelly—the neurons—in our brains give rise to the redness of red, the flavor of Marmite or paneer tikka masala or wine? Matter and mind seem so utterly unlike each other. One way out of this dilemma is to think of them really as two different ways of describing the world, each of which is complete in itself. Just as we can describe light as made up either of particles or as waves—and there's no point in asking which description is correct, because they both are, even though the two seem utterly dissimilar—the same may be true of mental and physical events in the brain.

But what about the self, the last remaining great mystery in science and something that everybody is interested in? Obviously self and qualia are two sides of the same coin. You can't have free-floating sensations or qualia with no one to experience them and you can't have a self completely devoid of sensory experiences, memories or emotions. (As we saw in Cotard's syndrome, when sensations and perceptions lose all their emotional significance and meaning, the result is a dissolution of self.)

What exactly is meant by the "self"? Its defining characteristics are fivefold. First of all, continuity: a sense of an unbroken thread running through the whole fabric of our experience with the accompanying feeling of past, present and future. Second, and closely related, is the idea of unity or coherence of self In spite of the diversity of sensory experiences, memories, beliefs and thoughts, we each experience ourselves as one person, as a unity.

Third is a sense of embodiment or ownership - we feel ourselves anchored to our bodies. Fourth, a sense of agency, what we call free will, being in charge of our own actions and destinies. I can wiggle my finger but I can't wiggle my nose or your finger.

Fifth, and most elusive of all, the self, almost by its very nature, is capable of reflection - of being aware of itself A self that's unaware of itself is an oxymoron.

Any or all of these different aspects of self can be differentially disturbed in brain disease, which leads me to believe that the self comprises not just one thing, but many. Like "love" or "happiness," we use one word, "self," to lump together many different phenomena. For example, if I stimulate your right parietal cortex with an electrode (while you're conscious and awake), you will momentarily feel that you are floating near the ceiling, watching your own body down below. You have an out-of-the-body experience. The embodiment of self—one of the axiomatic foundations of your self—is temporarily abandoned. And this is true of all of those aspects of self I listed above. Each of them can be selectively affected in brain disease. [Close quote]

(From Ramachandran's A Brief Tour of Human Consciousness, pp. 96-97)


[Open quote] I will begin with qualia. It seems quite obvious that qualia must have evolved to fulfill a specific biological function—they cannot be mere by-products (an "epiphenomenon") of neural activity. In 1997 I suggested that sensory representations that are themselves devoid of qualia might acquire qualia in the process of being economically encoded or "prepared" into manageable chunks as they are delivered to a central executive structure higher up in the brain. The result is a higher order representation that serves new computational goals. Let us call this second, higher-order, representation a metarepresentation. (Though I feel a bit uncomfortable using the prefix "meta," which is often employed as a disguise for fuzzy thinking—especially among social scientists.) One could think of this metarepresentation almost as a second "parasitic" brain - or at least a set of processes—that has evolved in us humans to create a more economical description of the rather more automatic processes that are being carried out in the first brain. Ironically this idea implies that the so-called homunculus fallacy—the notion of a "little man in the brain watching a movie screen filled with qualia"—isn't really a fallacy. In fact, what I am calling a metarepresentation bears an uncanny resemblance to the homunculus that philosophers take so much delight in debunking. I suggest that the homunculus is simply either the metarepresentation itself, or another brain structure that emerged later in evolution for creating metarepresentations, and that it is either unique to US humans or considerably more sophisticated than a "chimpunculus." (Bear in mind, though, that it doesn't have to be a single new structure—it could be a set of novel functions that involves a distributed network. Ideas similar to this have also been foreshadowed by David Darling, Derek Bickerton, Marvin Minsky and many others, although usually invoked for reasons other than the ones I consider here.) [Close quote]

(From Ramachandran's A BRIEF TOUR OF HUMAN CONSCIOUSNESS, pp. 98-99)

"If you have never been hated by your child, you have never been a parent." —Bette Davis [Yes! How did they develop the consciousnesses that they have?]

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