Hemispheric Specialization

The two hemispheres of the cerebral cortex are linked by the corpus callosum, through which they communicate and coordinate. Nevertheless, they appear to have some separate functions. The right hemisphere of the cortex excels at nonverbal and spatial tasks, whereas the left hemisphere is usually more dominant in verbal tasks such as speaking and writing. The right hemisphere controls the left side of the body, and the left hemisphere controls the right side.

When split-brain patients stare at the "X" in the center of the screen, visual information projected on the right side of the screen goes to the patient's left hemisphere, which controls language. When asked what they see, patients can reply correctly.

When split-brain patients stare at the "X" in the center of the screen, visual information projected on the left side of the screen goes to the patient's right hemisphere, which does not control language. When asked what they see, patients cannot name the object but can pick it out by touch with the left hand.




The Reticular Formation

The reticular formation is a network of neurons running through the hindbrain, midbrain, and forebrain that serves to arouse the higher parts of the brain.