Psychological Disorders

1

• Psychological Disorders
• Mood Disorders

2
Mood Disorders

• Mood disorders are a class of disorders marked
  by emotional disturbances that may spill over to
  disrupt physical, perceptual, social and thought
  processes.
• Major depressive disorder is a disorder in which
  people show persistent feelings of sadness and
  despair and a loss of interest in previous
  sources of pleasure.
• Onset can occur at any time, but most cases occur
  before age 40.
• The majority of people with depression (75 95)
  will experience a repeat episode.

3
Mood Disorders (cont.)

• Major depressive disorder (cont.)
• Depression is one of the most common mental
  illnesses (the lifetime prevalence is 16.2).
• However, prevalence is tied to gender. Women are
  twice as likely to be diagnosed with depression.
• This does not appear to be tied to biological
  differences between men and women and could
  result from greater stress and abuse that women
  experience.

4
Mood Disorders (cont.)

• Bipolar Disorder (once known as manic-depressive
  disorder) is marked by the experience of both
  depressed and manic periods.
• Manic periods are characterized by bouts of
  extreme exuberance and a feeling of
  invincibility.
• However, this state of elation alternates
  (sometimes suddenly) with periods of depression.

5
Mood Disorders (cont.)

• Bipolar disorder is much less common than
  depression (a unipolar disorder), affecting
  about 1 to 2.5 of the population.
• Peak age of vulnerability is between 20 and 29.

6
Mood Disorders (cont.)

• Etiology of mood disorders.
• Genetic vulnerability.
• Concordance rates, or the percentage of twin
  pairs or other pairs of relatives that exhibit
  the same disorder, suggests there is a genetic
  basis for mood disorders.
• Concordance rates for identical twins is 65 to
  72, whereas it is only 14 to 19 for fraternal
  twins who share fewer genes but the same
  environment.

7
Mood Disorders (cont.)

• Etiology of mood disorders. (cont.)
• Neurochemical factors.
• Mood disorders are correlated with low levels of
  two neurotransmitters in the brain
• Norepinephrine.
• Seratonin.
• However, it is unclear whether changes in these
  chemicals are the cause, or the result, of the
  onset of mood disorders.

8
Mood Disorders (cont.)

• Etiology of mood disorders. (cont.)
• Cognitive factors.
• Depression may be linked to negative thinking
  (see Figure 15.13).
• Specifically, Seligman (1974) proposes that
  depression is caused by learned helplessness,
  in which people become passive and give up in
  times of difficulty.
• Learned helplessness is also related to a
  pessimistic explanatory style in which people
  attribute setbacks to personal flaws.

9
Mood Disorders (cont.)

• Etiology of mood disorders. (cont.)
• Hopelessness theory, is another cognitive
  explanation of mood disorders in which other
  factors, in addition to a pessimistic explanatory
  style, push people into depression.
• Such factors include high stress and low
  self-esteem.
• Nolen-Hoeksema (1991, 2000) also asserts that
  those who ruminate about problems put themselves
  at risk for depression.

10
Mood Disorders (cont.)

• Etiology of mood disorders. (cont.)
• Interpersonal roots.
• Depression has also been correlated with
  interpersonal factors, such as poor social
  skills.
• However, it is unclear what the direction of
  cause and effect is, with regard to this
  correlation.
• Precipitating stress.
• There is also a link between stress and the onset
  of mood disorders.