1. Biology & Behavior

2. The Brain

3. Divisions of the Brain • Hindbrain, located at the rear base of the skull • Contains the cerebellum, the medulla, the pons

4. The Midbrain • Located just above the pons • Function: relays sensory information • Brain stem and reticular activating system

6. The Forebrain • The hindbrain and forebrain compose the brain’s central core • Thalamus (information relay) • Hypothalamus (motivation, emotion) • Higher-thinking processes

7. The Spinal Cord • Dura matter • Arachnoid • Pia matter • Cerebrospinal fluid • Gray vs white matter

8. THE BRAIN • Brainstem • Medulla: basic life support (breathing, swallowing, etc.) • Reticular Formation: arousal center (consciousness) • Thalamus • Sensory routing station except smell • Cerebellum • Fine motor skills (balance and coordination)

10. CEREBRAL CORTEX / CEREBRUM • Frontal lobe: higher order thinking • Temporal lobe: auditory processing • Occipital lobe: vision processing • Parietal lobe: recieves sensory input for touch and body position • Motor cortex: movement • Broca’s Area: expressive language * • Wernicke’s Area: receptive language * • Corpus Callosum: big body of nerve fibers that connects left and right brain *

11. Lobes of the Brain

12. Lobes and Their Functions • Frontal: planning of movements, working memory • Temporal: hearing, advanced visual processing, memory • Occipital: vision • Parietal: body sensations • Primary motor cortex: fine motor control

18. Brain Plasticity • Ability to modify itself after some types of damage • Explains why blind and deaf subjects have heightened senses • Amputee patients report feeling sensations in removed limbs • Life-long blind subject makes several errors on a language task after visual cortex was temporarily “knocked out” by magnetic stimulation

19. Higher-Thinking Processes • Cerebral cortex • Cerebrum

20. Hemispheres of the Brain • The cerebrum has two hemispheres • The corpus callosum

21. Two Hemispheres

22. Righthanded vs. Lefthanded • Handedness—a preference for using one hand • Not an absolute • 90% of people in the U.S. are righthanded • Theories: environmental vs. genetic

23. Problems Associated With Being a Lefty • Autism and dyslexia • Schizophrenia • Mental retardation • Alcoholism • Life expectancy

24. Split-Brain Surgery • Pioneered by Roger Wolcott Sperry 1913–1994 • Used to correct epileptic seizures

25. Splitting the Brain • Michael Gazzaniga, Roger Sperry, and others • Left side of the brain controls reading, writing, speaking, arithmetic reasoning, and understanding • By severing the corpus callosum seizures in epileptic patients can be reduced

26. Split Brain People • “the most fascinating people on earth” Gazzaniga • He * Art and spoon experiments • Some split brain people are frustrated by independent left hand • Some can draw pictures of two different objects simultaneously • Rock, Paper, Scissors????

28. Side Effects

32. Looking Inside the Brain

33. Techniques Used to Look Inside the Brain • Electrical recordings • Lesioning • Electrical stimulation • Brain imaging

34. Electrical Recordings Electro-encephalograph (EEG) Hans Berger Brainwave patterns

35. Lesioning • Brain tumors, strokes, head injuries all cause brain damage • H. Gardner, 1975 • Limitations/ experiments with animals

36. Electrical Stimulation of the Brain • ESB involves sending a weak electrical current into a brain structure in order to stimulate it • The current mimics brain wave voltage • Most ESB research is done on animals

37. Brain Imaging Techniques • CT (computerized tomography) scans • PET (positron emission tomography) scans • MRI (magnetic resonance imaging) scans

38. The CT Scan • Computerized tomography (CT) scan: a computer-enhanced x-ray of brain structure • Assembling the images • CT/least expensive procedure

39. Image From a CT Scan

40. PET Scans • Positron emission tomography (PET) scan • Radioactive chemicals are used as markers • Provides a color-coded map of the brain

41. MRI Scans • Magnetic resonance imaging (MRI) scan uses magnetic fields, radio waves, and computerized enhancement • Much more detailed than a CT scan

42. Brain Injuries

43. Brain Trauma • A physical accident where the head receives a severe blow. • Auto accidents, sports injuries

44. Types of Head Trauma • Concussion • Contusion • Laceration

45. Concussion • Temporary loss of consciousness • Causes no permanent damage to skull or brain tissue • Flaccid paralysis • Symptoms

46. Concussion

47. Contusions • Actual bruising of neural tissue • May cause a coma • Loss of speech, convulsions, disorientation, delusions

48. Lacerations • The most serious of brain injuries • A foreign object such as a bullet enters the skull • Brain tissue is destroyed

49. James Brady • Reagan’s press secretary • Shot March 30, 1981 • Wound to the head • Brady Bill

50. Cerebral Laceration • The case of Phineas Gage