Studying The Brain

1. Studying The Brain Lesson 6-2

3. Objectives • Identify the structure and functions of the human brain • Discuss the different ways psychologists study the brain

4. Introduction • Early Greeks thought the heart was the source of feelings and thought • Hippocrates observed the effects of head injuries on people’s thoughts.

5. The Three Brains • Hindbrain • at base of the skull • controls most life processes (eating, sleep, appetite, thirst, mating) • includes cerebellum, medulla and pons Brain

6. Hindbrain • cerebellum- controls posture and balance • medulla- controls breathing • pons- bridges messages between brain and spinal cord Brain

7. Midbrain • Integrates sensory information and relays it Brain

8. Forebrain • Includes thalamus- integrates sensory information, except smell • hypothalamus- controls hunger, thirst, body temperature, and sexual behavior Brain

9. Forebrain • Allows for higher level thinking • Outer layer is called cerebral cortex • Inner layer is the cerebrum Brain

11. H I N D M I D F O R E

12. Lobes of the Brain • Cerebrum is two sides • Corpus Callosum is a band of fibers that connects the two sides • Deep grooves that forms lobes

13. Lobes of the Brain • Occipital Lobe- processes visual info • Parietal Lobes- Sensory information • Temporal Lobe- hearing, memory, emotion, speaking • Frontal Lobe- organization, planning, creative thinking, and personality

14. Left and Right Hemispheres • Are almost mirror images • Left brain controls the right side of the body • controls speech for most people • controls mathematical ability and logic

15. Left and Right Hemispheres • Right hemisphere controls left side of the body • visual and spatial ability • puzzles • recognizing patterns • music and art • creativity and intuition

17. Psychosurgery • A prefrontal lobotomy has been preformed many times to alter psychopathic behavior • are very controversial when performed on prisoners • informed consent • role of prisons

18. Brain and Criminal Behavior • Recent studies show that men convicted of violent crimes are more likely to have abnormalities of their frontal lobe and their right hemisphere.

19. Split-Brain Operations • In Epileptics, split the corpus callosum to decrease number of seizures • seizure is massive uncontrolled electrical activity that begins in either hemisphere and spreads to the other

20. Split-Brain Operations • In Epileptics, split the corpus callosum to decrease number of seizures • seizure is massive uncontrolled electrical activity that begins in either hemisphere and spreads to the other

21. Split-Brain Operations • In Epileptics, split the corpus callosum to decrease number of seizures • seizure is massive uncontrolled electrical activity that begins in either hemisphere and spreads to the other

22. Activity • Right brain or left brain??

23. Activity • Right brain or left brain??

24. Split-Brain Operations • Roger Sperry did experiments on people with split brain operations • Nobel Peace prize in 1981 • Holds ball in right hand can say it is a ball, but put in left hand, can’t say it is a ball. • Showed each half had specialized functions

25. How Psychologists Study the Brain • Physiological Psychologists or Psychobiologists study the role of the brain in behavior

26. Recording • Electrodes- can be inserted into the brain to record electrical activity • electroencephalograph- EEG records electrical activity from whole areas of the brain

27. Stimulation • Electrodes can be used to set off the firing of neurons • Stimulate brains of patients during surgery to find out what function they perform • have been used to relieve pain of terminally ill cancer patients • experimented with use to control violent emotional behavior

28. Lesions • Cut or destroy a small portion of an animals brain • They then monitor the animal for changes in behavior • Assume those changes are controlled by that part of the brain • Rhesus monkey study • no longer fearful and aggressive

29. Accidents • 1848- Phineas Gage • RR foreman • showed good judgement, restraint, worked well with others • tamping iron enters Gage’s head right below left eye (13 pounds, 3 feet long) • survived, but personality changed greatly

30. Further Investigation Phineas Gage: 19th century living in Cavendish, Vermont. One of his jobs was to set off explosive charges in large rock in order to break them into smaller pieces. On one of these instances, the detonation occurred prior to his expectations, resulting in a 42 inch long, 1.2 inch wide, metal rod to be blown right up through his skull and out the top. The rod entered his skull below his left cheek bone and exited after passing through the anterior frontal lobe of his brain.

31. Remarkably, Gage never lost consciousness, or quickly regained it (there is still some debate), suffered little to no pain, and was awake and alert when he reached a doctor approximately 45 minutes later. He had a normal pulse and normal vision, and following a short period of rest, returned to work several days later. However, he was not unaffected by this accident.

32. Accidents • Dr. Paul Broca discovered the connection between left brain and speech • area now called Broca’s area

33. Images • Computer Axial Tomography (CAT) • xrays pass around and through a person’s head • radiation absorbed based on density of brain tissue • transforms into a 3 dimensional picture

34. Images • Positron Emission Topography (PET) • captures a picture as different parts are being used • Uses a radioactive solution into the blood and then measures the amount absorbed by blood cells.

35. Images • Magnetic Resonance Imaging (MRI) • study both structures and activity • pass radio frequencies through the brain • used to identify tumors or brain damage