B IOLOGY AND B EHAVIOR The Brain

O BJECTIVE Identify the major structures of the brain, and explain the functions of each structure.

T ODAY ’ S GOALS Get over notes you took

A SSOCIATION A REAS The association areas serve mainly to shape information into something meaningful on which we can act Activity in the association areas then integrates the information so that we see a meaningful form such as a tree.

L ANGUAGE A BILITIES Almost all right-handed people have language functions based in the left-hemisphere 2 out of 3 left-handed people have language functions based in the left-hemisphere too. Only small number is based in right-hemisphere 2 key language areas: Broca’s Area– frontal lobe– controls area of the face used for speaking Wernicke’s area- temporal lobe– pieces together sounds and sights Damage to areas could cause aphasia: difficulty with specific aspects of understanding or producing language

E XAMPLES OF A PHASIA Wernicke’s area: Find it difficult to understand speech, may be able to speak but often their speech is meaningless If a person is asked to describe a picture of 2 boys stealing cookies behind a woman’s back, one person responded “Mother is away her working her work to get her better, but when she’s looking the two boys looking the other part. She’s working another time” Geschwind, 1979) Broca’s area: when this area is damaged, people speak slowly and laboriously, using simple sentences. IF they want to say “The three bananas are lying on the table” may produce only “bananas lie table”

L EFT VS R IGHT H EMISPHERE One hemisphere does play a special role in language, while the other hemisphere plays a special role in feelings. However, both hemispheres are involved in logic, creativity, and intuition Not true that some people are “left brained” and others are “right-brained”

M ETHODS OF STUDYING THE B RAIN The study of accidents and brain injuries Phineas Gage Electrical Stimulation of the Brain: Jose Delgado (1969) used electrical stimulation of the brain to show how an animal could be made to change behavioral patterns. Implanted an electrode into a bull’s brain: bull dramatically stopped his charge and circled to the right * Rats James Olds and Peter Milber implanted electrodes into rats hypothalamus Rats press the lever and felt pleasure– would press 100 times a minute and would rather press the lever than to eat or drink. Results may vary

T HE E LECTROENCEPHALOGRAM (EEG) A device that records the electrical activity of the brain Detect small amounts of electrical activity called brain waves Certain brain wave patterns are associated with feelings of relaxation and with sleep Can help diagnose some kinds of psychological disorders and to help locate tumors.

S CANS Computers generate images of the brain Info about brain damage & abnormalities, early cancer diagnosis CAT scan: Computerized axial typography Moving ring passes X-ray beams around and through the head. 3-D view of the brain that can be displayed on a video monitor MRI scan: Magnetic Resonance Imaging: Lie in a powerful magnetic field; radio waves then cause parts of the brain to give off extra energy. Energy is measured from multiple angles and is translated by computer into a visual image of the brain’s anatomy. MRI can show details more clearly and is more powerful than a CAT scan PET scan: Positron emission tomography: Show the activity of the brain rather than a snapshot of the brain at a given time. Which parts of the brain are most active