PSYC 415 -- Dr. King -- Notes on Depression

classification
   reactive vs. endogenous
   unipolar vs. bipolar
several different "types"
   major depressive disorder (MDD) - endogenous (no obvious environmental cause)
   bipolar disorder - alternating periods of depression and mania
   dysthymia - depression that is a reaction to life events
prevalence - book says 3-7% (MDD); about twice as prevalent in women as men
symptoms - despair, guilt, unworthiness, hopelessness, apathy, anhedonia,
   amotivational state; 15% attempt suicide
major depressive disorder is heritable
   twin studies -69% concordance in MZ twins; 13% concordance in DZ twins
   studies of biological relatives
   genes coding for the serotonin transporter are implicated
traditional talking psychotherapies have not been very useful (for MDD)
drug treatment
   MAOIs - monoamine oxidase inhibitors
   tricyclic antidepressants
   SSRIs - selective serotonin reuptake inhibitors
   SNRIs - serotonin and norepinephrine reuptake inhibitors
   lithium carbonate - for bipolar disorder
20-40% of patients are drug resistant
other treatments that have proven successful
   electroconvulsive therapy (ECT)
   sleep deprivation (temporarily)
   phototherapy (for seasonal affective disorder)
   deep brain stimulation - to the subgenual anterior cingulate cortex
   vagus nerve stimulation
monoamine hypothesis - some combo of serotonin, norepinephrine, and/or dopamine
   are deficient in depressed individuals
   most popular theory for decades
   depletion of brain MAs can cause depression (reserpine, tryptophan depletion)
   suicidal depression is associated with low 5-HIAA levels
   based primarily on the kinds of drugs that work - monoamine agonists
role of dopamine is unknown
sleep cycles (and circadian rhythms in general) are abnormal in depressives
   seasonal affective disorder
   disorganized sleep cycles
      very little if any deep slow-wave sleep
      scattered and broken up REM periods
      frequent awakenings
   sleep deprivation is an effective treatment for depression
      total sleep deprivation has a temporary effect
      selective REM deprivation over several weeks has a longer lasting effect
      all drugs that suppress REM sleep are effective antidepressants
Wu and Bunney theory - we produce a depressogenic substance while we sleep
   which is broken down during waking
the resiliance theory
   stress and stress hormones damage brain cells
   most of us can repair this damage - our brains are resiliant
   people prone to depression cannot repair this damage for some reason
   brain damage (e.g., repeated concussions) make people much more susceptable
   antidepressant drugs and ECT promote neurogenesis in the hippocampus
amygdala, subgenual anterior cingulate cortex, and prefrontal cortex are
   implicated by scanning studies
depression and the frontal lobes - possible role of executive functions
in summary
   something biological is clearly going on in people with MDD
   50 years of research into what that might be has led to no breakthroughs
   as of now, drug therapy, cognitive-behavioral therapy, and ECT are the best
      we have to offer