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When we were discussing neuron function and structure I wasvery interested in the distinction between white and grey matter. I’ve seenmany brain scans before and I’ve never understood the color differences (I hadalways thought they represented differences in neuron activity). Learning aboutwhite and grey matter made me interested in the differences between these twobrain regions. If the neocortex consists of both white and grey matter, itshould be able to send messages all over the body via the axon bundles. If theneocortex has access to regions outside the nervous system, it would suggestthat human beings, and other mammals have fully integrated the neocortex intoour functioning. Unlike other adaptations that species have undergone, it seemsthat the neocortex has now become essential to our survival, not just ourdominance over other species. I think that the neocortex is capable ofperforming tasks independently, but it also needs messages from other portionsof the nervous system, as well as the body. So, if the neocortex were removedfrom the human body, it would create no useful signals. But if the wholenervous system were placed on a Petri dish, it would continue to form signals.

It would make sense to me that individuals are born with ahigh percent of grey matter, and a smaller percentage of white matter. Humansare born with the ability to shape their neural pathways in a number of ways.We don’t have the ability to create infinite numbers of pathways because oflimitations placed on us by genetics and environment, but we do have a widerange of opportunities for pruning. Once we had established our neuralconnections and created nerves, the white matter would become more prevalent.At first, I believed that it would be more beneficial to  have a higher percentage of gray matterin the brain because it meant that learning would be more flexible, but aftersome consideration, I now believe that it is most beneficial to establish whitematter. In fact, individuals with disorders such as autism are known to have ahigher proportional of gray matter in areas of the neocortex (http://health.usnews.com/usnews/health/healthday/071128/autistic-children-have-more-gray-matter-in-brains.htm)