Do human brains work in two parts?

The two sides of the brain are connected by the corpus collosum which allows the two sides of the brain to communicate with each other.

When the corpus collosum is severed very strange things happen because the two sides of the brain can no longer communicate with each other. The person seems normal but is in fact now two individuals in the same body.

In one case where a patient’s corpus collosum had to be surgically severed to stop life threatening seizures a pencil was shown to each eye. When the pencil was shown to only the right eye (which is connected to the left brain) the patient could identify the pencil but couldn’t explain what it was used for; when the pencil was shown only to the left eye the patient could explain what it was used for but couldn’t name it.

We tend to think of individuals as left-brain dominant when they are scientists or mathemtitians and as right-brain dominant when they are artists or musicians but the truth of the mater is we need both sides for any complex activity. Trained musicians do a great deal of analysis with their left brain when they perform or actively listen to music while scientists and mathematicians show a great deal right brain activity because of the creativity needed when they brainstorm problems.