392 Chapter 11 Psychological Disorders
A person’s vulnerabilities (in genetic predisposi-
tions, personality traits, or habits of thinking)
interact with stressful events (such as violence,
death of a loved one, or losing a job) to produce
most cases of major depression. Let’s consider the
evidence for four contributing factors:1
genetic predispositions or neurotransmitter imbal-
ances. Major depression is a moderately heri-
table disorder, but the search for specific genes
has so far been unsuccessful (Frances, 2013). One
focus of investigation has been the genes that
regulate serotonin, a neurotransmitter involved
in mood. An early theory held that depression
results from abnormally low levels of this neu-
rotransmitter; indeed, that theory was the impetus
for the development of antidepressants, designed
to boost the availability of serotonin in the brain.
However, many years of research have failed to
support the notion that depression results from
a simple neurotransmitter deficiency. Depleting
animals of serotonin does not induce depression,
nor does increasing brain serotonin necessar-
ily alleviate it. The fact that some antidepres-
sants raise serotonin levels does not mean that
low serotonin levels caused the depression—avulnerability-stress
models Approaches that
emphasize how individual
vulnerabilities interact
with external stresses or
circumstances to produce
mental disorders.
You are about to learn...
• the difference between major depression and
the blues.
• four contributing factors in depression.
• how some people can think themselves into
depression.Depressive and Bipolar
Disorders
In the DSM-5, depressive disorders include a num-
ber of conditions that can cause persistent sad,
empty, or irritable moods, accompanied by physi-
cal and cognitive changes that affect the per-
son’s ability to function in everyday life. People
often speak of feeling “depressed,” and of course
everyone feels sad from time to time. These feel-
ings, however, are a far cry from serious clinical
depression.Major Depression LO 11.8, LO 11.9
Major depression involves emotional, behavioral,
cognitive, and physical changes severe enough
to disrupt a person’s ordinary functioning. Some
episodes can last for months, subside, and later
recur. People with major depression feel sad,
despairing, and worthless. They feel unable to
get up and do things; it takes an enormous effort
even to get dressed. They may overeat or stop
eating, have difficulty falling asleep or sleeping
through the night, have trouble concentrating,
and feel tired all the time. They lose interest in
activities that usually give them satisfaction and
pleasure.
Major depression occurs about twice as often
among women as among men (Rohde et al.,
2013). However, because women are more likely
than men to talk about their feelings and more
likely to seek help, depression in males is prob-
ably underdiagnosed. Men who are depressed
often try to mask their feelings by withdrawing,
abusing alcohol or other drugs, driving recklessly,
or behaving violently (Canetto, 1992; Kessler
et al., 1995). As Susan Nolen-Hoeksema, a lead-
ing depression researcher, put it, “Women think
and men drink.”
One of the great mysteries of depression is
that most people who undergo a “depressing”
experience do not become clinically depressed, and
many people who are clinically depressed have not
had objectively “depressing” experiences (Monroe
& Reid, 2009). Most researchers thus account for
depression in terms of a vulnerability-stress model:major depression
A disorder marked by
excessive sadness, loss
of interest in usual activi-
ties, feelings of worthless-
ness and hopelessness,
thoughts of suicide, and
physical symptoms (such
as fatigue and loss of
appetite).
Long before she became famous for writing the Harry
Potter books, J. K. Rowling suffered incapacitating
depression. She contemplated suicide, but the need to
remain alive for her infant daughter kept her from killing
herself. Later, she told an interviewer that she was never
ashamed of having been depressed. On the contrary, she
said, she was proud of herself for getting through that
difficult time.