Stress

1. Stress Stressful Video

3. What is stress? • Stress has been defined as “the rate of wear and tear in the body” or, from Brainfacts • any external stimulus that threatens homeostasis So what is homeostasis and give an example? The property of a system that regulates its internal environment and tends to maintain a stable, relatively constant condition of properties: ie blood sugar, temperature or pH

5. Why stress? • Stress can help the body in the short term, Acute stress • can provide extra strength and energy to cope with a challenge • protects the body and brain • Can increase memory during stressful situations • helps reestablish homeostasis So is stress always good In the long term, no. Long term, or Chronic Stress can be very harmful.

6. Name the 3 sections of the nervous system activated by stress • Voluntary (Somatic) nervous system • Autonomic nervous system • Neuroendocrine system

7. The Immediate ns response to stress 1.) Somatic (voluntary) NS • sends messages to muscles

8. The Immediate ns response to stress 2.) The Autonomic Nervous System What are the subgroups under this division of the NS? • Sympatheticnervous system (fight or flight) and parasympathetic nervous systems (calming, homeostatic) • (MEMORY HINT: I feel sympathetic toward you if you are chased by a bear and a PARAchute brings you down slowly) • Sympathetic NS triggers – • Increasedblood flow to muscles • Reducedblood flow to skin, kidney, digestive tract. • If this lasts too long, it can be harmful.

10. The Immediate ns response to stress 3.) Neuroendocrine system What is the primary brain structure that communicates/influences with the endocrine system? The Hypothalamus What endocrine organ does the hypothalamus directly influence? The pituitary gland What are the 2 major stress hormones and what endocrine organ releases them? Epinephrine (adrenaline) and Cortisol (which is a type of glucocorticoid), both released by the adrenal gland

13. The Immediate ns response to stress 3.) Neuroendocrine system • Brain sends signal to glands to release stress hormones • Hypothalamus releases CRF(corticotrophin-releasing factor) which stimulates the pituitary to release ACTH (adrenocorticotrophic hormone), which stimulates the release of stress hormonesfrom the adrenal glands.

14. Lets get This figured out somatic • A stress is detected and requires your body to respond. The first thing you could do is move, this requires your _____________ nervous system. • At the same time, your body is preparing for a stressful situation, which requires the ______________ nervous system. • In order for your body to coordinate a uniform response, the nervous system links up to the endocrine system (neuroendocrine system) using the nervous system structure known as the _____________, which directly communicates the endocrine structure known as the _____________. • More specifically, the _____________ releases signals called _________________________________ to the anterior _________________ and causes it to release a hormone known as ___________________________. • The hormone ____________ released from the anterior ________ then signals the _______________ to release _____________. • The two types of _______________ are _______________ & ________________. autonomic hypothalamus Pituitary gland hypothalamus CRF (corticotrophin-releasing factor) pituitary gland ACTH (adrenocorticotrophic hormone) pituitary ACTH Adrenal gland Stress hormones Stress hormones Epinephrine Cortisol

15. The Immediate ns response to stress 3.) Neuroendocrine system (still continues) • Stress hormones: • Epinephrine (also called adrenaline) • Released quickly in response to stress • Puts body in state of arousal (fight-or-flight) • Cortisol • Released more slowly in response to stress (5 min delay) • Mobilizes energy and delivers it to muscles • Increases Cardiovascular efficiency • Turns Down immediate non-essentials such as feeding, digestion, growth, and reproduction • Influenced by daily cycles – acts as “wake up” signal in the mornings. • Both increase the activity of the immune system • Both are released by the adrenal glands

16. Take a look at the bodies response to stress. How are these beneficial? • Thank you Teona, Meaghan, Sydni, & Nicole for this picture

17. Chronic Stress • How is stress today different from the stress of our Nomadic ancestors? Modern stressors often do not require that we respond with muscular activities (running or fighting). How could this be bad? Our system is has evolved so that exertion would help to return your body to homeostasis. Instead, your body may stay roused up, long after the initial stressor is gone.

18. Take a look at the bodies response to stress. How could these be harmful in response to modern stressors? • Thank you Teona, Meaghan, Sydni, & Nicole for this picture

19. Chronic Stress • Overexposure to cortisol and epinephrine can lead to: • weakened muscles • suppression of immune system • hypertension (high blood pressure) • abdominal obesity (“belly fat”) • atherosclerosis (hardening of arteries) • Stress also can contribute to sleep loss. • Elevated levels of glucocorticoids can delay the onset of sleep, and sleep deprivation raises glucocorticoid levels, setting off a vicious cycle.

20. Chronic Stress • Stress-related disorders include: • colitis, (swollen colon) • hypertension, • clogged arteries, • impotency, • loss of sex drive, • irregular menstrual cycles, • diabetes, • and maybe cancer

21. Chronic Stress • Overexposure to glucocorticoids also increases the number of neurons damaged by stroke. • Prolonged exposure to glucocorticoids before or immediately after birth can cause a decrease in the normal number of brain neurons and smaller brain size. What might cause this? For some reason, the adrenal is producing too much cortisol. Could be a tumor in the pituitary, cuasing too much ACTH to be relased, signalling the release of too much cortisol, or a tumor in the adrenal itself, causing too much cortisol to be created.

22. Random related disease • Cushing’s syndrome: • Rapid weight gain-Central obesity • Moon Face • Hyperhydrosis (sweat a lot) • Hirsutism (male pattern hair growth) • Muscle & Bone weakness • Hypertension • Immune suppression… • Can be caused by overmedication of steroids, or by tumors in the pituitary or adrenal.

23. Glucocorticoids and the immune response • Hydrocortisone is a synthetic (man-made) glucocorticoid. What does it do? Hydrocortisone suppresses the immune response. So it stops inflamation. How does this make sense in relation to natural glucocorticoids influence over the immune system during stress. While stress initially increases or promotes the immune system, glucocorticoids will work as immunosuppressors, reversing the initial stress response, and ensuring there is not an over-response by the immune system.

24. ChronicStress and the immune system http://www.youtube.com/watch?v=wyFPUvG-66E

25. Review Questions • What is the Brainfacts definition for stress? • Any external stimulus that threatens homeostasis • The somatic nervous system responds to stress by sending signals to ______. • Muscles • In response to stress, how does the Sympathetic Nervous System affect skin, the kidneys, and the digestive tract, and why? parts of the body that blood decreases is the • Blood flow to these areas is decreased and prioritized to ‘essential organs for the ‘fight or flight’ response • The two major stress hormones are • Epinephrine (adrenaline and Glucocorticoids (Cortisol) • Of the two stress hormones named above, which is ‘fast-acting’ compared to the other • Epinephrine is a more immediate response while the glucocorticoids could take up to 5 minutes to respond

26. perceived danger-Psychological stress • Physical stressors typically are not chronic, although they may be reoccurring (very hard manual labor, athletics…) • Social & Psychological stressors • No physical outletto return body to normal • May be chronic • Give examples

27. personality or behavior • How we deal or perceive event in our lives affects our stress hormone level. • Hostile and irritable people are at higher risk for heart attacks. • Case study: Researchers studied two groups of men categorized as having high or low hostility. Both were subjected to harassment. • Scientists found that harassed men with high hostility scores had larger increases in levels of stress hormones, muscle blood flow, and blood pressure. • Thus, for those people with personality traits that include high levels of hostility, learning to reduce or avoid anger could be important to avoid cardiovascular damage.

28. Aging & The Brain What happens to our brain when we get old?

29. Aging-What happens when we get old? True or false? • In normal aging, we should expect to see severe declines in memory, intelligence, verbal fluency, and other tasks FALSE! • Severe declines in memory, intelligence, verbal fluency, and other tasks is usually due to some disease process, and not necessarily part of normal aging.

30. Aging-What happens when we get old? • Scientists views on what happens to the brain as we age are changing due to the larger sample of people who are living longer. • What was the average lifespan of someone in the early 1900s? • What was the avg. life span in 2007? 47, So only 4% of the total pop was over 65 years old 78, now over 39 million, or 13% of the population is over 65

31. Brain Development and Decline Image from: http://www.answers.com/topic/neural-crest Image from: http://www.ratbehavior.org/DumboRatMutation.htm

32. Growth Timeline of the Brain Infant: overproduction of neurons, pruning Child/Adolescent: critical period, large numbers of synapses formed 20s: peak in long term memory, creativity, max brain weight 50s: accelerated brain volume loss, noticeable changes in memory and cognition Cont’d Aging: Hippo-campus and amygdala vulnerable; Dementia ~70yr. Images from: http://clipartspot.net/baby-clipart-12.html; http://www.clipartpal.com/clipart_pd/education/teenager1.html; http://www.clipartheaven.com/show/clipart/food_&_drink/drinks_-_alcoholic/beer_mugs_1-gif.html; http://image455910.seesaa.net/article/181307100.html?googleimage; http://www.clipartheaven.com/show/clipart/anatomy/brain_-_mechanical-gif.html

33. What can happen to brain function as you age?

34. Hypothesized Causes of brain aging • Aging genes turned “on” • Genetic mutations and deletions • Hormone changes • Immune system changes • Free radical damage

35. The Aging Brain • No change • A minority of people • Normal Decline • Majority of people • Subtle and selective changes • Forming memory of recent events affected • Slower responses and slowed processing of new information • Senile Dementia • 50% of people over age 85 • A progressive and severe impairment of mental function that interferes with daily living • Alzheimer’s Disease • Cerebrovascular disease

36. What is dementia • Dementia is a progressive and severe impairment in mentalfunction that interferes with the activities of daily living, and includes a number of different diseases: • Alzheimer’s disease is the most common. • cerebrovascular disease, • Pick’s disease, • and Lewybody disease. • Together, the dementias affect as many as 6.8 million people in the U.S, and at least 1.8 million of those cases are severe.

37. Pathologies that damage the Brain • Neurodegenerative diseases such as Alzheimer's and Parkinson’s disease. • Stroke • Both lead to damage or destroyed brain cells. • Responses to Neuordegeneration: • Very few stem cells limits neurogenesis • Neurons can respond by expanding dendrites, creating new synapses, and fine-tuning existing synapses

38. Non-pathologic changesthat occur with age…

39. At what age does the brain reach its maximum weight? • 20 • What is the most common form of demensia? • Alzheimer's • The average lifespan of a person, as of 2007, is __, which has risen since 1900 when it was ___. • 78; 47

40. Selective Attention • “ability to attend to some stimuli while disregarding others that are irrelevant to the task at hand” • Stroop task • Not affected by age, but information processing speed is.

41. Stroop Task Red Blue Yellow Green Orange Purple Magenta White Black Yellow Turquoise Blue Purple Green Orange Red Red Blue Yellow Green Orange Purple Magenta White

42. Working Memory • “hypothesized as the fundamental source of age-related deficits in a variety of cognitive tasks” • Definition: “active manipulation of information that is currently being maintained in focal attention” • Example of working v. pure “short term memory”…

43. Numbers 5 36 9 41 102 Now try to remember and repeat back the numbers you just saw. 5 36 9 41 102 Now try to say the numbers backwards. 102 41 9 36 5

44. Long-term Memory • Episodic – most vulnerable to damage • What was your favorite vacation? • Latest memory to develop. Unique to humans? • With age, less details. Also less consolidation (hippocampus, combine all senses into one memory) • Familiarity stays intact

45. Long Term Memory Continued • Semantic Memory – knowledge about the world. QUIZ TIME! 1. What is the capitol of NY? 2. Who gave the Emancipation Proclamation? 3. What country has the greatest number of people? 4. Do insects have vertebrae? Albany Lincoln China No, they have an exoskeleton

46. Long Term Memory Continued • Prospective Memory –remembering to do things • HOMEWORK! Image from: http://www.bbisd.org/vnews/display.v/SEC/Front%20Page%7CHomework%20Help

47. Speech and Language • Improve with age: • Vocabulary • Discourse skills Image from: http://donitabaker.edublogs.org/language-arts/scholastic-book-clubs/

48. Lifestyle Variables • Enriched environment • Aerobic Exercise • Everyone has their own experiences – make unique synapses

49. Image from: http://www.syracusecrunch.com/News/Detail/2367/2008-09 Overall, more decline in new info.Less decline in learned/stored memory Image from: http://www.webweaver.nu/clipart/music/piano.shtml

50. Normal aging or senile dementia? CASE #1: Mildred is a 72 year old woman who has worked as a waitress in a small diner in Syracuse for over 40 years. She loves her job because she gets to talk with customers and meet a lot of new people each day. You are one of her regular customers and have noticed that Mildred started to write your orders down recently, although she previously took all her orders by memory. Although she recognizes you each morning and greets you with a big smile, sometimes she calls you the wrong name, later correcting herself. Other changes you noticed are that she now needs a calculator to add up the cost of your meal and has you repeat yourself if there is a lot of commotion in the diner, as if she can’t focus on more than one thing at a time. Nevertheless, Mildred continues to be a great waitress and seems very happy. She tells you many stories about when she was younger and how much the city has changed. She also talks about her grandchildren very often. Still, you wonder, is Mildred beginning to have senile dementia, or is this a normal part of aging?