Re-reading: old words, new meanings

I am rereading Gerald Edelman’s and Giulio Tononi’s book, A Universe of Consciousness, and once again am struck by how much these guys knew and thought. The first time through a few years back I took in the idea of reentrance, the notion that much of brain function is characterized by reentrant processing, i.e., circuits form loops and amplify or mitigate informational patterns by recirculating the results. This is not for feedback in a corrective process but more feedforward for a constructive one and that is one important distinction for a symbolizing species. I have kept this in mind quite a bit as I have read and thought about our brains.

This time I am struck by how much I missed or neglected to ponder to a fuller extent about two other concepts. They say our brain functions are shaped by two other processes they call degeneration and value. Now I am working to understand fully the new meanings of these two words.

Degeneration, heretofore in my experience, meant falling apart or, in crude folk parlance, someone who molests children or had otherwise degenerated from being fully human. Edelman and Tononi use the word to denote how different processes can end in the same result. Now this is a curious insight and on third reading, profound. Consider how perceptual processes, the neural variability of which must be considerable when you consider the system from retina to object recognition in the cortex, result in object constancy, i.e., different processes, same result. Going further, consider how brains differ so grandly from each other e.g., 10,000,000,000 neurons, 10x that many glia, and exponentially more synapses connecting them all in some complex multiplicity of systems, yet each essentially functions to the same ends. Imagine, and this can only be imagined, if every computer was different from every other in hardware and software yet still processed unstructured input to the same result. In the realm of cognition, consider how different neural patternings can elicit the same memory, how our memories are almost holographic in their flexibility or how many different exemplars are known as falling into the same category. So degeneration is an amazing generalization about neural processes.

What about value? The meaning in biology with which I am familiar lies in the processing result of the system organized around the amygdala and with dopamine, i.e., does the stimulus have survival value (fight/flight) or indicate approach/avoidance, i.e., is it positive or negative in value? Edelman and Tononi use the term, as best I can tell, to denote evolutionary value; that is, once a structural or functional feature has appeared in evolution and is found to be adaptive, further evolution tends to elaborate upon that value. I really like this one.

Remember that sexual reproduction appeared long eons ago and continues to work in many ways because of its value, e.g., introduces controlled variability to the genetic streams. Consider conspecific communication (one of my favorites) that has evolved from finding a mate to social cooperation to cultural organization. The value of conspecific communication is especially evident in the development of empathy in both parenting and social relations. For a specific example, consider that oxytocin, one of the primary hormonal instigators of parental and altruistic feelings and behaviors, appeared on the scene some 400 million years ago and over the course of evolution has transformed to different forms in more powerful brains to promote prosocial relationships. Now that’s real value, and I won’t even begin to talk about the linguistic and aesthetic symbols of our conspecific communication.

So old words and wildly new meanings, a good reason for re-reading. Well, off to ponder some more (and work in the garden).

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