Biological Causes & Treatments of Major Depression PDF

BIOLOGICAL CAUSES & TREATMENTS OF MAJOR DEPRESSION, CONT.  A Quick Review: Causes of MDD We’ve Considered So Far I. Behavioral (stress, decreased rewards, learned helplessness) II. Cognitive (pessimistic attributional style, hopelessness theory, rum...

BIOLOGICAL CAUSES & TREATMENTS OF MAJOR DEPRESSION, CONT.  A Quick Review: Causes of MDD We’ve Considered So Far I. Behavioral (stress, decreased rewards, learned helplessness) II. Cognitive (pessimistic attributional style, hopelessness theory, rumination, neg cognitive triad, automatic neg thoughts, cognitive errors) III. Interpersonal (loss, role disputes, role transitions, skills) IV. Psychodynamic (dependency, introjected hostility) V. Sociocultural (lifestyles, cohorts, power, gender) VI. Genetics VII. Neurotransmitters (serotonin, norepinephrine, maybe dopamine, maybe glutamate) VIII. Causes of Major Depression: Hormones Hypothalamic-pituitary-adrenal axis (HPA axis): Connection to stress: HPA axis is chronically overly reactive, increasing levels of hormones like cortisol (which inhibits receptors for monoamines) Evidence: MDD is assoc w abnormally high levels of cortisol. Are women’s hormones related to major depression? Estrogen and progesterone… – About 3% of women have Premenstrual Dysphoric Disorder; however, even here it doesn’t appear to be due to hormones. – At menopause there is no increased risk of depression. – There is an increase in depression in girls around the age of puberty: Does this result from biological, psychosocial, and/or cultural factors??  IX. Causes of Major Depression: Abnormal functioning in specific regions or circuit of the brain Left prefrontal cortex (unusually low or high activity in different parts of prefrontal cortex) – Attention, goals, motivation, problem solving Brodmann Area 25 = subgenual cingulate (overactive) Hippocampus (smaller, & lower activity) – Memory, fear-related learning – Has lots of serotonin receptors; & stress ê neurogenesis Amygdala (enlarged, & higher activity) – Negative emotion, rumination Communication bet these areas is often problematic.  X. Causes of Major Depression: Immune System Dysfunction People with MDD often have: – Lower activity of lymphocytes (white blood cells that help fight off disease) – Higher production of pro-inflammatory cytokines (cause inflammation) Chronic stress has these same effects on the immune system. XI. Causes of Major Depression: Biological rhythm dysfunction Circadian rhythms Subjective sleep problems and changes in sleep architecture (e.g., reduced REM latency) Sleep deprivation, esp REM sleep deprivation, can have antidepressant effects. XII. Causes of Major Depression: Modern Lifestyles Therapeutic Lifestyle Change (TLC) targets 6 protective lifestyle elements: (e.g., Ilardi, 2009) Omega-3 fatty acids Engagement Physical exercise Sunlight exposure Social support Sleep Reports: response is 3 * higher than usual antidepressant treatment. Other Biological Treatments for MDD Light therapy (for seasonal affective d/o) Ketamine as a newer antidepressant (IV or nasal spray) Electroconvulsive therapy (ECT) Repetitive transcranial magnetic stimulation (rTMS) (a Dr. Oz clip: https://www.youtube.com/watch?v=vuBt2Z1oIV8 (4:33-7:20) Vagus nerve stimulation (VNS) Deep brain stimulation  Case Study: Janet -- What is troubling Janet? -- Is there a diagnosis that fits well? -- What are contributing/ causal factors? -- What approaches to treatment might work, and why?