Specialization in the Cerebral Hemispheres

1. Specialization in the Cerebral Hemispheres Sidney Brunson Blakely Powell Paige Dillenbeck Phillip Skelton Evelyn Peirce

2. In many cases, the functioning of the left and right hemispheres is symmetrical. • The same functions are located in roughly the same places on each hemisphere • However, the hemispheres do differ-each hemisphere is specialized for particular abilities

3. Cortical Localization • By the 1700s, people knew that brain injury could cause paralysis/ loss of sensation • By the 1800s, it was shown that specific functions would be lost if particular brain areas were destroyed • Scientists were beginning to debate the notion of cortical localization (localization of function) • The idea that particular areas of the human brain are associated with particular functions

4. Pierre Paul Broca • French surgeon and neuroanatomist in the 1860s • Treated a series of patients that had difficulty speaking but could understand written and spoken language • Autopsies showed brain damage in the lower left frontal lobe • This area is now known as Broca’s Area • Plays a crucial role in speech production

5. Karl Wernicke • German neurologist • Discovered an area in the left hemisphere that, when damaged, produced a different type of language disturbance • Patients could not understand written/spoken language but could speak quickly and easily • Their speech sometimes made no sense • Autopsies found damage in the lower left frontal lobe • This area is now known as Wernicke’s Area

7. The split brain • A split brain operation is used to stop or reduce recurring seizures in severe cases by cutting the corpus callosum. • The corpus callosum is the thick band of axons that connects the two hemispheres of the brain.

8. The left hemisphere • Specializes in words and letters, language sounds, verbal memory ,speech ,writing, reading, and grammar rules.

9. The right hemisphere • The right hemisphere of the brain specializes in faces, emotional expression, nonverbal memory, emotional tone of speech, sense of direction, music, and geometric patterns.

10. Roger Sperry • Roger Sperry is known for his research using split brain patients to investigate the relationship between brain and behavior. • In the 1960s, Roger Sperry began to unravel the mystery of the left and right hemispheres

11. Plasticity • Plasticity is the brain’s ability to change function and structure. • the two types of plasticity are: • Functional-the brain’s ability to shift functions from damaged to undamaged brain areas • Structural –the brain’s ability to change its physical structure in response to learning , active practice, or environmental influences