The Human Brain

The Human Brain Our brains weigh about three pounds and are divided into two similar looking but functionally different hemisphere, the right hemisphere and the left hemisphere. Both of which are connected by a large bundle of nerves called the corpus collosum. In some people with severe seizure disorders such as epilepsy, it was found that if this bundle of nerves was severed their seizure would either cease or a the very least be better …

…to emotion and physiological regulation that remain connected. Split brains, actually, are not really split into two but instead form a Y. The fact that basic responses (such as the fear-conditioned responses like the heart rate increase to a visual conditioned stimulus) do cross from one hemisphere to the other even when the corpus callosum has been cut, showing that it crosses in lower pathways in the brain, might indicate the evolution of human consciousness.