Lecture 22: Health and Disorders Flashcards
(34 cards)
Health and Well-being
• Not just biological, medical: beliefs and attitudes affect health as well
Health psychology
Integrates research on health and psychology, applying psychological principles to promote health and well-being
Well-being
Positive state; striving for optimal health and satisfaction with life
Biopsychosocial model
Health and illness result from interacting biological, psychological, and social factors
Our perceptions shape behavior
- Perception as to what is “risky” - e.g. flying vs. driving - can alter behavior that increases risk of death
- Perceptions can also alter physiological responses - e.g. the placebo effect
Placebo effect
• (Good example of biopsychosocial model)
• Improvement attributed to inert drug/treatment
• Psychological aspects:
– To work, the individual must believe that it does
– Part of the effect: reduced anxiety about health and treatment
Placebo effect: physiology
• Placebos for pain trigger release of endogenous opioids on responders
– Effect blocked if administered naloxone, which blocks opiate receptors
• Mechanism might involve increased frontal cortex -> descending pain-regulation systems
• Reduces activity in thalamus, ACC, insula
– Reduced ACC activity associated with decreased perception of pain
– Subjects trained to reduce ACC activity based on biofeedback during scanning
Placebo effect (continued)
- Effects of placebo on activation of u-opioid receptor-mediated transmission
- ACC, insula, nucleus accumbens, prefrontal cortex…pain + cognition
Stress and coping
- Stress: behavioral, psychological, physiological responses that occur when events match/exceed ability of organism to respond in a healthy way
- Coping: response organism makes to avoid, escape, minimize an aversive stimulus
- Both positive and negative events can be stressful: eustress vs. distress
Yerkes-Dodson Law: 1908
- Simple task: focused attention, flashbulb memory, fear conditioning
- Difficult task: impairment of divided attention, working memory, decision-making and multitasking
Hebb’s version: Yerkes-Dodson Law
- increasing attention and interest
- optimal arousal and optimal performance
- impaired performance b/c of strong anxiety
Physiology of stress
• “stress” - nonspecific term to describe either stress response (physiological) or situation eliciting stress response
• fight or flight response
– ANS (sympathetic)
– Endocrine systems (adrenal glands secrete epinephrine, NE, steroid stress hormones such as cortisol)
HPA axis
- Hypothalamus-Pituitary-Adrenal axis helps the body prepare to respond to the stressor
- Stress affects organs even after stressor has been removed
What triggers the stress response?
• Several pathways activate the hypothalamus
• CRH triggers release of ACTH from anterior pituitary
• ACTH -> glucocorticoid release from adrenal medulla
– Glucocorticoids = steroid hormones
– Involved in protein and carbohydrate metabolism
– Cortisol: increases and maintain [glu] in blood; glu synthesis in liver, inhibition of uptake by muscles and fat, stimulation of fat breakdown
Your brain, relaxed
- vmPFC regulates emotion
- Dorsal and lateral PFC regions regulate thought & action
- PFC connections control intelligent regulation of behavior, thought, and emotion
Your brain, stressed
• Amygdala –> stress pathways (hypothalamus, brainstem) –> high NE and DA release
• Impairs PFC regulation, strengthens amygdala
• Strengthens fear conditioning
– Bias toward habitual motor responses
– Impairs WM and attention
Gender differences in stress responses?
• Majority “flight or fight response” males
• Taylor and colleagues (2006) argue that women have “tend and befriend” response
– Care and protect offspring and forming social alliances to reduce risk
– Maximally adaptive
– Oxytocin levels are high for women, but not men, who are stressed
General adaptation syndrome
• Consistent pattern of how body responds to stress
• Three stages:
– Alarm stage: prepares the body to fight or flee
– Resistance: defenses prepare for a longer, sustained attack against the stressor
– Exhaustion: variety of physiological and immune systems fail
Does stress make us sick? (Psychoneuroimmunology)
• Interactions between environmental stimuli, nervous and immune systems
• Stress increases likelihood of infection diseases
– Increases glucocorticoid release
– Glucocorticoids suppress immune system
– Increases glucocorticoid release
• Lower levels of immunoglobulin antibodies even in response to mood changes
Cohen says: yes!
- Short-term boosts the immune system; chronic stress weakens it
- Swabbed healthy volunteers’ noses w/ cold virus
- Those who reported highest levels of stress prior to exposure developed worse cold symptoms than those who reported being less stressed
Stressed out monkeys
- Colony of vervet monkeys in Kenya
- Hierarchical society: “bottom” rung monkeys bullied by others
- Decreased monkeys showed gastric ulcers, enlarged adrenal glands
- Destruction of neurons in hippocampus
Stressed out humans
• Signs of neural degeneration in torture victims
• Maltreatment early childhood -> decreased volume of dmPFC
• Long-term effects of increased glucocorticoids:
– Immune system suppression (initially adaptive to reduce inflammation, becomes maladaptive)
Long-term stress and the brain
- Repeated stress –> remodeling connections of the amygdala –> concurrent remodeling in the PFC and hippocampus
- Chronic stress also decreases neurogenesis & neuron number in the hippocampus
- Most of these stress-induced changes in the hippocampus and PFC are reversible over time
Psychological disorders
- Psychopathology: literally, sickness or disorder of the mind
- Hippocrates suspected physiological basis in relative amount of humors (bodily fluids) - imbalance –> mania, melancholia, phrenitis
- Last 200 yrs: viewed as medical condition w/ physiological (particularly neural) basis
