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I anticipate some more satisfactory ideas (or questions, or failures) tomorrow morning, but I've been thinking about the role of the neocortex and decided to throw out a few thoughts.

One small idea: mammals are warm-blooded, so they may have a greater need to be aware of their own bodily systems. If the neocortex receives signals from the thalamus (as Margaux said), the reception of those signals may ensure that the brain sends out signals to other bodily organs, thereby carrying out essential processes like generating heat or cooling the body down. The neocortex could be kind of like a conductor, ensuring that one small box in the brain gets its message out to the rest of the brain and then the body.

What's really getting to me: in the previous comment, Nana brought up the idea of "intelligence" as a possible, but scientifically problematic, result of the neocortex. While her anteater example confuses me, it also gives me food for thought. What if "intelligence" doesn't just mean physical agility or sensory processing but relates more to self-consciousness? Awareness of the self seems to me like something humans may possess more of than other animals, even though others clearly have some level of it too.

In thinking about the child-rearing example mentioned in another comment, I'm also starting to think that a complex web of social behavior might be a result of the neocortex. Maybe that is like a kind of awareness of species -- or awareness of the self as one among many? as a human? as a function of society? Although it is difficult to separate humans from other mammals, the idea that all mammals do a certain amount of teaching and babysitting, even though some mammals end up as solitary creatures, does seem to suggest that the neocortex causes some sort of instinct to form a community, to ensure the success of procreation, to pass on behaviors not just through genes but also through parenting.

Another idea that isn't fully formed: why do humans have so much of the spongy stuff? Tuesday's class made me think that most of the stuff we see from the outside, when looking at a brain, is white matter -- tracts, paths, connections. Thinking back on things I've learned from PBS, the Discovery Channel, and high school, I also know that the human brain constantly forms new passageways as we learn new things or change our behavior. (To use the lingo I've learned from class, our neurons are always rearranging.) Most of the brain -- or at least the white stuff? -- isn't even in use, at least not until our neurons carve our new connections. What are those new connections? Are they skills, calculations, friends, memories?

Lots of other creatures can recognize things or relations, like their young or their nests, but does that mean they remember when they befriended their egg-layers? I'm not sure. I do know that humans, as they grow, learn not only to be aware of their current environment, their status in relation to the outside world, and many of the stimuli they're receiving, but also to compare the current moment to past moments, to associate themselves and their identity with other people, to study their inner states and thoughts, and to perceive or infer emotions and thoughts in others. Maybe the number of available white folds in the neocortex -- the density of its connections -- determines how much of that awareness or ability a mammal can develop, regardless of the overall size of the neocortex or the brain.