Health Psychology

1. Health Psychology Chapter 3: Biological Foundations of Health and Illness Aug 31-Sep 5, 2007 Classes #6-7

2. Biological Roots of Behavior • Franz Gall (1758-1828) • Austrian physicist who invented phrenology • He felt that bumps on the skull could reveal our mental abilities and character traits • Introduced as being scientific but its use was exploited by “quacks on gullible individuals” • Became similar to that of astrology, palm-reading and tarot • Although, ill-fated theory was laughed at by scientific community of that day – it may have had some validity • Localization of brain functions somehow hit the mark

3. The Nervous System • Electrochemical communication system that enables us to think, feel, and behave • Complex beyond comprehension • Although, human brains are more complex our nervous systems and those of animals operate in a similar fashion – advantage of this is experimentation

4. The Nervous System • Allows researchers to study simple animals such as squids and sea slugs to help us better understand the organization of our own brains

5. Divisions of the Nervous System • Consists of two systems • Central Nervous System • Brain and spinal cord • Peripheral Nervous System • Which connects the CNS to the rest of the body

6. Organization of the Nervous System

7. Peripheral Nervous System • Two components: • Somatic Nervous System • Transmits sensory input to the CNS from the outside world and directs motor output • Autonomic Nervous System • Controls glands and muscles of our internal organs – “automatic pilot”

8. Autonomic Nervous System • Dual system: • Sympathetic Nervous System • Arouses the body • Parasympathetic Nervous System • Calms us down

9. Endocrine System: Taking the slow lane • Unlike the speedy nervous system which zips messages from eyes to brain to hand in a fraction of a second, endocrine messages use the slow lane • May take several seconds or more as bloodstream carries a hormone from an endocrine gland to its target tissue

10. Endocrine System • Hormones are chemical messengers • Influence all aspects of our lives – growth, metabolism, reproduction, moods, etc. • Strives for homeostasis (balance) by responding to stress, exertion, internal thoughts, etc.

12. Epinephrine • Involved in energy and glucose metabolism

13. Illnesses Associated With Epinephrine • Depression – too low levels

14. Norepinephrine • Plays a role in attention and arousal • Used by sympathetic nervous system to prepare us for action

15. Illnesses Associated With Norepinephrine • Depression • Chronic stress depletes this neurotransmitter and can lead to depression • Note: • Aerobic Exercise is found to protect the brain from this depletion – so go out and run a mile or two if your down in the dumps

16. How does the brain govern behavior? • 3 Principle layers of the brain: • Brainstem • Limbic System • Hippocampus • Amygdala • Hypothalamus • Cerebral Cortex

17. Brainstem (or Hindbrain) • The brain’s innermost region… • Begins where the spinal cord enters the skull and swells slightly forming the medulla • Towards the rear of the brainstem is the cerebellum – this is linked to memory and its major function is muscular control

18. Limbic System • Hippocampus • This structure plays a key role in allowing us to store new information • Problems here may cause Alzheimer's – these individuals have trouble processing declarative memories • Milner (1968): the classic case of H.M.

19. Limbic System • Amygdala • Emotional control center of the brain – major influence on aggression and fear • Emotional memories as well • Alzheimer’s ??? • Kluver and Bucy (1939) • Demasio (1994)

20. Limbic System • Hypothalamus • Major influence on hunger, thirst, body temperature, and sexual behavior • Olds and Milner (1954)

21. Cerebral Cortex • Makes us distinctively human – much higher developed than in animals • Motor Cortex – involved in the conscious initiation of voluntary movements in specific parts of the body including hand, knee, foot and head • Fritsch and Hitzig (1870) • Delgado (1969a) • Delgado (1969b) • Penfield (1975)

22. Cerebral Cortex • Sensory Cortex • receives information from our senses • Visual cortex • visual info • Auditory cortex • auditory info • Somatosensory cortex • info from skin • Association cortex • involved in complex cognitive tasks associating words with images • Broca’s area (aphasia) • Wernicke’s area (aphasia)

23. Function of the Cardiovascular System • Assist in gas transport. • Deliver nutrients, hormones • Remove waste products from the cells • Assist in temperature regulation • Assist in balancing body fluids and helps prevent dehydration

24. Systems of the Heart • The heart functions to contract and propel blood through the two blood transport systems. • Pulmonary system • Systemic system

25. Pulmonary System • Within the pulmonary system blood is transported to and from the lungs. • The right ventricle propels deoxygenated, carbon dioxide rich, blood to the lungs where carbon dioxide is released and oxygen is picked up. • After gas exchange the blood returns to the left atrium of the heart.

26. Impact of Cardiovascular Disease • Affects more than 60 million Americans each year • Results in nearly 1 million deaths each year • Cost nearly $275 billion

27. Cardiovascular Disease • Cardiovascular disease (CVD) is the number one cause of death in the United States. • Most reported deaths are related to coronary artery disease

28. Forms of Cardiovascular Disease • Coronary artery disease • Hypertension (Chronic high blood pressure) • Cerebral vascular accidents (strokes) • Peripheral vascular disease • Valvular heart disease • Congenital heart disease • Congestive heart failure

29. Coronary Artery Disease • Primary form of heart disease • A disease involving waxy plaque build-up in the arteries

30. Coronary Risk Factors • Primary Risk Factors: Factors that have been definitively associated with or directly cause coronary artery disease. • Smoking, inactivity, hypertension • Secondary Risk Factors: Factors believed to contribute to or advance the severity of CAD. • Gender, age

31. The Respiratory System • At the level of the individual cell: respiration involves energy-producing chemical reactions that require oxygen • At the level of the whole organism, respiration is the process of taking in oxygen from the environment and ridding the body of carbon dioxide.

32. The Lungs • Left and right lungs: • are in left and right pleural cavities • The base: • inferior portion of each lung rests on superior surface of diaphragm

33. The Right Lung • Has 3 lobes: • superior, middle, and inferior • separated by horizontal and oblique fissures

34. The Left Lung • Has 2 lobes: • superior and inferior • are separated by an oblique fissure

35. Relationship between Lungs and Heart Figure 23–8

36. Lung Shape • Right lung: • is wider • is displaced upward by liver • Left lung: • is longer • is displaced leftward by the heart forming the cardiac notch

37. Components of the Digestive System Digestive Tract • Gastrointestinal (GI) tract or alimentary canal • Is a muscular tube • Extends from oral cavity to anus

38. 6 Functions of the Digestive System • Ingestion: • occurs when materials enter digestive tract via the mouth • Mechanical processing: • crushing and shearing • makes materials easier to propel along digestive tract • Digestion: • is the chemical breakdown of food • into small organic fragments • for absorption by digestive epithelium

39. Secretion: • is the release of water, acids, enzymes, buffers, and salts • by epithelium of digestive tract • by glandular organs • Absorption: • movement of organic substrates, electrolytes, vitamins, and water • across digestive epithelium • into interstitial fluid of digestive tract • Excretion: • removal of waste products from body fluids

40. THE IMMUNE SYSTEM We all get sick sometimes...but then we get better. What happens when we get sick? Why do we get better?

41. ANATOMY OF THE IMMUNE SYSTEM • The immune system is localized in several parts of the body • immune cells develop in the primary organs -bone marrow and thymus (yellow) • immune responses occur in the secondary organs (blue)

42. ANATOMY OF THE IMMUNE SYSTEM • Thymus– glandular organ near the heart – where T cells learn their jobs • Bone marrow – blood-producing tissue located inside certain bones • blood stem cells give rise to all of the different types of blood cells • Spleen– serves as a filter for the blood • removes old and damaged red blood cells • removes infectious agents and uses them to activate cells called lymphocytes • Lymph nodes – small organs that filter out dead cells, antigens, and other “stuff” to present to lymphocytes • Lymphatic vessels – collect fluid (lymph) that has “leaked” out from the blood into the tissues and returns it to circulation

43. PASSIVE IMMUNITY While your immune system was developing, you were protected by immune defenses called antibodies. These antibodies traveled across the placenta from the maternal blood to the fetal blood. Antibodies (Y) are also found in breast milk. The antibodies received through passive immunity last only several weeks.

44. YOUR ACTIVE IMMUNE DEFENSES   Innate Immunity - invariant (generalized) - early, limited specificity - the first line of defense Adaptive Immunity - variable (custom) - later, highly specific - ‘‘remembers’’ infection

45. What influences one’s behavior: Nature or Nurture? • The age-old debate: • Is it genes or is it the environment?

46. Twin Studies • Monozygotic • Identical twins (one-egg) • Dizygotic • Not identical (fraternal) twins • Resemble one another as much as any brother or sister would

47. “The Jim Twins” • Thomas Bouchard’s University of Minnesota twin studies • Extraordinary similarities between Jim Springer and Jim Lewis • Uncanny coincidences? • Any limitations to this study?

48. These guys shared a flushing the toilet gene… • Bouchard (1979) • Part of Bouchard’s twins study… • Oskar Stohl and Jack Yulfe were raised in environments with more obvious differences

49. And you thought it was because you were incompatible… • Is there a genetic risk of divorce? • McGue and Lykken (1992) • 1516 pairs of same-sex twins • 722 MZ and 794 DZ • MZ > DZ

50. What is a gene made out of? • Genes are made from chromosomes. People have 23 pairs of chromosomes. • DNA consists of a double helix, whose parallel strands consist of both pairs held together by hydrogen bonds. • Each chromosome in the DNA contains instructions for stringing together amino acids. • These instructions are used in different combinations with the chemicals adenine (A), thiamine (T), guanine (G) and cytosine (C).