Sperry was granted numerous awards over his lifetime, including the California Scientist of the Year Award in 1972, the National Medal of Science in 1989, the Wolf Prize in Medicine in 1979, and the Albert Lasker Medical Research Award in 1979, and the Nobel Prize for Medicine/Physiology in 1981 that he shared with David H. Hubel and Torsten N. Wiesel. Sperry won this award for his work with "split-brain" patients. The brain is divided into two hemispheres, the left and right hemispheres, connected in the middle by a part of the brain called the corpus callosum. In "split-brain" patients, the corpus callosum has been severed due to the patients suffering from epilepsy, a disease that causes intense and persistent seizures. Seizures begin in one hemisphere and continue into the other hemisphere. Cutting the corpus callosum prevents the seizures from moving from one hemisphere to the other, which then prevents seizures from occurring, thus allowing the patients to function normally instead of suffering from continuous seizures.