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Chapter 12 Emotional Behaviors

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  • 1.Chapter 12 Emotional Behaviors

2. What is Emotion?

  • Psychologists define emotion in terms of three components:
    • Cognition
    • Readiness for action
    • Feeling

3. What is Emotion?

  • Emotional situations arouse the autonomic nervous system.
  • Each situation evokes its own special mixture of sympathetic and parasympathetic arousal

4. 5. What is Emotion?

  • TheJames-Lange theoryof emotion suggests that the autonomic arousal and skeletal action occurs first in an emotion.
  • The emotion that is felt is the label that we give the arousal of the organs and muscle

6. What is Emotion?

  • James-Lange theory leads to two predictions:
    • People with a weak autonomic or skeletal response should feel less emotion.
    • Increasing ones response should enhance an emotion

7. What is Emotion?

  • Research indicates the following:
  • Paralyzed people report feeling emotion to the same degree as prior to their injury
  • People with pure autonomic failure still report feeling emotion but less intensely.
    • Pure autonomic failure -output from the autonomic nervous system to the body fails.
  • Suggests other factors are involved in the perception of emotion.

8. What is Emotion?

  • According to the James-Lange theory, emotional feelings result from the bodys action.
  • Panic attacksare marked by extreme sympathetic nervous system arousal.
    • Only if perceived as occurring spontaneously.

9. What is Emotion?

  • Creating certain body actions may also slightly influence emotion.
    • smiling slightly increases happiness.
    • Inducing a frown leads to the rating of stimuli as slightly less pleasant.
  • Indicates that perception of the body's actions do contribute to emotional feeling
  • However, bodys actions are not required.
    • Example: M bius syndrome

10. 11. 12. What is Emotion?

  • Emotional experiences arouse many areas of the brain.
  • Thelimbic systemincludes the forebrain areas surrounding the thalamus
    • traditionally been regarded as critical for emotion.
  • PET and fMRI studies also suggest many other areas of the cerebral cortex, especially the frontal and temporal lobes, are activated during an emotional experience.

13. 14. What is Emotion?

  • Measurement of evoked responses indicate the brain is specialized to attend strongly to facial expressions.
  • Emotions tend not to be localized in specific parts of the cortex.
  • A single emotion increases activity in various parts of the brain.

15. 16. What is Emotion?

  • Localization in the brain seems to exist for the emotion of disgust.
  • Theinsular cortexis strongly activated during exposure to stimuli perceived as disgusting.
    • Also the primary taste cortex.
    • Also reacts to frightening stimuli so not completely dedicated to disgust.

17. What is Emotion?

  • The two hemispheres of the brain play different roles in emotion.
  • Activation of the frontal and temporal areas of the left hemisphere is associated with approach and theBehavioral Activation System .
    • Marked by low to moderate arousal.
    • Can characterize either happiness or anger.

18. What is Emotion?

  • TheBehavioral Inhibition System (BIS)is associated with increased activity of the frontal and temporal lobe of the right hemisphere.
    • Increases attention and arousal.
    • Inhibits action.
    • Stimulates emotions such as fear and disgust.

19. What is Emotion?

  • Differences in frontal cortex activity relates to personality.
  • People with greater activity in the left hemisphere tend to be happier, more out-going and friendlier.
  • People with greater left hemisphere activity tend to be socially withdrawn, less satisfied with life, and prone to unpleasant emotions.

20. What is Emotion?

  • The right hemisphere seems to be more responsive to emotional stimuli than the left.
  • Damage to the right temporal cortex causes problems in the ability to identify emotions of others.

21. What is Emotion?

  • Functions of emotions include:
  • adaptive values (fear leads to escape, anger lead to attack, etc.)
  • allow us to make quick decisions
  • help us make moral decisions.

22. What is Emotion?

  • The consequences of our decisions have emotional considerations.
  • Emotions are an important component to moral decisions.
  • Failure to anticipate the unpleasantness of an event can lead to bad decision making.
  • Contemplating moral decisions activates the prefrontal cortex, cingulate gyrus, and amygdala.

23. 24. What is Emotion?

  • Damage to the prefrontal cortex impairs decision making.
  • Leads to impulsive decision-making without pausing to consider consequences.
  • Stems form failure to anticipate unpleasantness of an outcome

25. Attack and Escape Behaviors

  • Attack and escape behaviors are closely related physiologically and behaviorally.
  • Corresponding behaviors are anger and fear.

26. Attack and Escape Behaviors

  • Pain, threat or other unpleasant stimuli can trigger an attack behavior.
  • Attack behaviors are associated with increased activity in the corticomedial area of the amygdala.
  • After experiencing a provocation, people are more likely to attack for a period of time afterwards.
  • An initial attack behavior increases the probability of a second attack behavior.

27. 28. Attack and Escape Behaviors

  • Environmental factors associated with increased violent tendencies include
    • Exposure to lead
    • Smoking behavior of mother during pregnancy
      • The effect is particularly strong if the mother smoked and also had complications during pregnancy.
  • Both may impair brain development

29. 30. Attack and Escape Behaviors

  • Twins studies suggest genetic contribution to the likelihood of violent behavior.
  • Monozygotic twins resembled each other much more than dizygotic twins with regard to violent and criminal behavior.
  • Attempts to identify a specific gene have found only a weak effect.

31. Attack and Escape Behaviors

  • Violence is particularly enhanced with both a genetic predisposition and an early troubled environment.
    • Example: Interaction between MAO Alevels and childhood maltreatment

32. 33. Attack and Escape Behaviors

  • Hormones also influence aggressive behavior.
  • Male aggressive behavior is influenced by the hormone testosterone.
  • On average, males engage in moreaggressive and violent behaviors than do females.
  • Research shows that men with the highest rates of violent behavior also have slightly higher testosterone levels.

34. 35. Attack and Escape Behaviors

  • Testosterone alters the way people respond to stimuli.
  • Testosterone may increase the response of the amygdala to angry expressions.
  • Decreases ability of the cerebral cortex to identify and regulate emotion.

36. 37. Attack and Escape Behaviors

  • Studies also suggest a connection between aggressive behavior and low serotonin release.
  • Turnoveris the amount of a neurotransmitter that is released and resynthesized by neurons.
  • Valzellis (1973) study with male juvenile mice found that social isolation decreased serotonin turnover and increased aggressive behavior.

38. Attack and Escape Behaviors

  • 5-hydroxyindoleacetic acid (5-HIAA)is a serotonin metabolite found in the blood, cerebrospinal fluid, and urine that allows researchers to infer turnover rate.
  • High levels of 5-HIAA imply much serotonin release and turnover.
  • Research with monkeys has demonstrated that low levels of 5-HIAA increases the probability of attack on larger monkey
    • few survived past age 6.

39. Attack and Escape Behaviors

  • Monkeys with high levels of 5-HIAA were more likely to survive.
  • Evolution seems to select for an intermediate amount of anxiety and aggression.
  • Evolution might also select for high aggressive behaviors.
    • may die young, but are more likely to achieve a dominant position within the troop.

40. Attack and Escape Behaviors

  • In human studies, low serotonin turnover has been linked to:
    • People with a history of violent behavior and violent crime.
    • People who attempt suicide by violent means.
    • Recurrent violent behaviors.
      • A simple blood tests does not enable the reliable identification.

41. 42. Attack and Escape Behaviors

  • Changes in diet can alter serotonin synthesis.
    • Example: tryptophan and serotonin synthesis

43. Attack and Escape Behaviors

  • Serotonin activity an also be influenced by genetics.
  • Genes control the production of tryptophan hydroxylase.
  • Tryptophan hydroxylase is the enzyme that converts tryptophan into serotonin.
  • People with less active form of this enzyme are more likely than others to report frequent anger and aggression.

44. Attack and Escape Behaviors

  • The role of serotonin is very complicated and should not be thought of as the anti-aggression transmitter.
  • During aggression, the brain releases serotonin.
  • Clinical depression is linked to low serotonin.
  • High levels of serotonin may inhibit a variety of impulses.

45. Attack and Escape Behaviors

  • Proneness to approach, avoidance, and anxiety varies with the situation.
  • Amygdala is one of the main areas for integrating both environmental and genetic influences and then regulating current levels of anxiety.
  • Fear and anxiety are not necessarily associated with the desire to flee.

46. Attack and Escape Behaviors

  • Thestartle reflexis the extremely fast response to unexpected loud noises.
    • found in young infants and suggest fear is built-in and unlearned
  • Auditory information stimulates an area of the pons that commands the tensing of the neck and other muscles.
    • Information reaches the pons within 3 to 8 milliseconds after
    • The startle response occurs within two-tenths of a second.

47. Attack and Escape Behaviors

  • Current mood or situation can modify the reaction
  • Startle reflex is more vigorous if already tenses
  • Cells in the amygdala, especially the basal lateral and central nuclei, receive information from pain, vision, and hearing circuits.
  • Axons extend to areas in the midbrain that relay information to the nucleus in the pons.
  • The relay enhances the startle reflex.

48. 49. Attack and Escape Behaviors

  • Output from the amygdala to the hypothalamus controls autonomic fear responses.
  • Axons extending from the amygdala to the prefrontal cortex regulate approach and avoidance responses.

50. Attack and Escape Behaviors

  • Damage to the amygdala interferes with:
    • the learning of fear responses
    • retention of fear responses previously learned
    • interpreting or understanding stimuli with emotional consequences

51. Attack and Escape Behaviors

  • In the early 1900s, studies of monkeys with Kluver-Bucy syndrome illustrated the effects of amygdala damage.
  • Monkeys with this syndrome are calm and placid and display less than normal fear of snakes and larger, more dominant monkeys.
  • Also alters social behaviors in that they have decreased ability to interpret threat gestures.
  • Amygdala damage can also lead to an increase in the approach motive.

52. Attack and Escape Behaviors

  • fMRI studies suggest the amygdala responds strongly to emotional stimuli and facial expressions.
    • Not necessarily associated with just fear.
  • Activity is strongest when the meaning is unclear and requires some processing.
  • Responds more strongly to an angry face directed toward the viewer and frightened faces directed elsewhere.
  • Amygdala also responds to stimuli not consciously perceived.

53. 54. Attack and Escape Behaviors

  • In humans, damage to the amygdala does not result in the loss of emotion.
  • Damage to the amygdala impairs the processing of emotional information when the signals are subtle or complicated.
  • Amygdala damage affects the ability to judge trustworthiness in people.
  • People with amygdala damage focus on emotional stimuli the same as irrelevant stimuli or details.

55. Attack and Escape Behaviors

  • Amygdala damage also affects the ability to recognize emotions specifically in photographs or pictures.
    • Effect is particularly strong for fear or disgust.
  • Amygdala damage does not affect the ability to recognize fear in real life.
    • Attention to certain aspects of the face (eyes versus mouth) may account for the difference.

56. 57. 58. Attack and Escape Behaviors

  • Genetic variations in amygdala arousal may thus underlie some of the variations of anxiety in the population and related disorders.
  • Arousal of the amygdala relates to the tendency to experience some negative emotions.
  • Excessive fear and anxiety disorders are associated with hyperactivity in the amygdala

59. Attack and Escape Behaviors

  • Drugs intended to control anxiety alter activity at amygdala synapses.
  • The main excitatory neuromodulator in the amygdala is CCK, and the main inhibitory transmitter is GABA.
    • Injections of CCK-stimulating drugs into the amygdala enhance the startle response.
    • Drugs that increase GABA activity trigger panic.

60. 61. Attack and Escape Behaviors

  • Benzodiazepinesare the most commonly used anti-anxiety drugs.
    • Examples: dizepam (valium), alprazolam (xanax)
  • Benzodiazepines bind to theGABA Areceptor , and facilitate the effects of GABA.
  • Benzodiazepines exert their effects in the amygdala, hypothalamus, midbrain, and other areas.

62. 63. Attack and Escape Behaviors

  • Diazepam-binding inhibitor (DBI)is a naturally occurring protein which attaches to the same sites as benzodiazepines and blocks their effects.
  • Endozepinesare neuromodulators that include DBI and other related proteins that work to increase levels of fear and anxiety.
  • Variations in genes controlling endozepines may relate to peoples probability of developing anxiety disorders.

64. Attack and Escape Behaviors

  • Ethyl alcohol has behavioral effects similar to benzodiazepines..
  • Alcohol enhances GABA effects.
  • An experimental drug Ro-15-4513 blocks the effect of alcohol on the GABA Areceptors complex.

65. 66. Stress and Health

  • Behavioral medicineemphasizes the effects on health of diet, smoking, exercise, stressful experiences, and other behaviors.
  • Emotions and other experiences influence illness and pattern of recovery.

67. Stress and Health

  • Hans Selye (1979) definedstressas the non-specific response of the body to any demand made upon it.
  • Threats on the body activate a general response to stress called thegeneral adaptation syndrome .

68. Stress and Health

    • The General Adaptation Syndrome:
    • Alarm stage- characterized by increased sympathetic nervous system activity.
    • Resistance stage- sympathetic response declines, the adrenal cortex releases cortisol and other hormones that enable the body to maintain prolonged alertness.
    • Exhaustion stage- occurs after prolonged stress and is characterized by inactivity, vulnerability, and decreased energy to sustain heightened responses.

69. Stress and Health

  • Sapolsky (1998) argues that the nature of todays crises are more prolonged.
    • Accounts for widespread stress-related illnesses and psychiatric problems in industrial societies.
  • Long-term, inescapable issues activate the general adaptation syndrome which is harmful to our health over time.

70. Stress and Health

  • Stress activates two systems in the body:
    • The sympathetic nervous system - fight or flight response that prepares the body for brief emergency responses
    • TheHPA axis- the hypothalamus, pituitary gland, and adrenal cortex.

71. 72. Stress and Health

  • The HPA axis becomes the dominant response to prolonged stressors.
  • Activation of the hypothalamus induces the pituitary gland to secreteadrenocorticotropic hormone (ACTH) .
  • ACTH stimulates the adrenal cortex to secrete cortisol.
  • Cortisol helps to mobilize energies to fight a difficult situation.

73. Stress and Health

  • Theimmune systemconsists of cells that protect the body against viruses and bacteria by producingleukocytes(white blood cells).
    • B-cells leukocytes that mature in the bone marrow and secrete antibodies.
      • Antibodies Y-shaped proteins that attach to particular kinds of antigens.
      • Antigens surface proteins that are antibody-generator molecules

74. Stress and Health

    • T cells attack intruders directly and help other T cells or B cells to multiply.
    • Natural killer cells leukocytes that attack tumor cells and cells that are infected with viruses.
  • Prolonged increased cortisol levels impair the immune system.

75. 76. Stress and Health

  • During an infection, leukocytes and other cells produce small proteins calledcytokines.
    • Combat infection and communicate with the brain to inform of illness.
  • Cytokines in the brain produce symptoms of illness.
    • Fever, sleepiness, lack of energy etc.
    • Sleep and inactivity are the bodies way of conserving energy to fight illness.

77. Stress and Health

  • Psychoneuroimmunologydeals with the way in which experiences alter the immune system.
  • Also deals with how the immune system influences the central nervous system.

78. Stress and Health

  • In response to a stressful experience, the nervous system activates the immune system.
  • Immune system increases production of natural killer cells, leukocytes and cytokines.
  • The cytokines can trigger symptom of illness as a reaction to the stress itself.

79. Stress and Health

  • Prolonged stress response is damaging to the body.
  • Prolonged increase of cortisol detracts from the synthesis of proteins of the immune system.
  • Prolonged stress of longer than a month significantly increases the likelihood of illness.

80. Stress and Health

  • Prolonged stress can also be harmful to the hippocampus and can affect memory.
  • Cortical enhances metabolic activity in the body.
  • When metabolic activity is high in the hippocampus, the neurons are more sensitive to damage by toxins or over-stimulation.
  • Stress also impairs the adaptability and the production of new hippocampal neurons.

81. Stress and Health

  • A variety of ways exist to reduce stress or control our response to it:
  • Breathing routines, exercise, meditation, distraction, dealing with the problem.
  • Social support from a loved one helps to reduce stress.
    • Reduces response in several brain areas including the prefrontal cortex.

82. Stress and Health

  • Posttraumatic stress disorder(PTSD) occurs in some people after terrifying experiences and includes the following symptoms:
    • Frequent distressing recollections.
    • Nightmares.
    • Avoidance of reminders of the event.
    • Exaggerated arousal in response to noises and other stimuli.

83. Stress and Health

  • Studies have revealed most PTSD victims have a smaller than average hippocampus.
  • PTSD victims showlower than normal cortisol levels after the trauma.
  • People with low cortisol levels may be ill-equipped to combat stress and more prone to the damaging effects of stress.