DEPRESSIONor pleasure in almost all activities and exhibits at
least four other symptoms from the following list:
marked weight loss or gain when not dieting,
constant sleeping problems, agitated or greatly
slowed-down behavior, fatigue, inability to think
clearly, feelings of worthlessness, and frequent
thoughts about death or suicide. Anyone experi-
encing these symptoms for a prolonged period of
time should see a doctor or psychiatrist immediately.
Another type of depression is bipolar disorder,
formerly called manic-depressive illness. Not near-
ly as prevalent as other forms of depressive disor-
ders, bipolar disorder involves interspersed peri-
ods of depression and elation or mania. Sometimes
the mood switches are dramatic and rapid, but
most often they are gradual. When in the de-
pressed cycle, individuals have any or all of the
symptoms of a depressive disorder. When in the
manic cycle, individuals tend to show inappropri-
ate elation, social behavior, and irritability; have
disconnected and racing thoughts; experience se-
vere insomnia and increased sexual appetite; talk
uncontrollably; have grandiose notions; and dem-
onstrate a marked increase in energy. Mania often
affects thinking, judgment, and social behavior in
ways that cause serious problems and embarrass-
ment. For example, unwise business or financial
decisions may be made when an individual is in a
manic phase. Bipolar disorder is often a chronic
condition. For more details on types of depres-
sion, including symptoms, see either a good text-
book on abnormal psychology (e.g., Sarason and
Sarason 1999), DSM-IV (American Psychiatric As-
sociation 1994) or use the search term ‘‘depres-
sion’’ on the web site for the National Institute of
Health (http://search.info.nih.gov/).
THEORIES OF DEPRESSIONMost theorists agree that depression can be best
studied using what health psychologists refer to as
a biopsychosocial approach. This holds that depres-
sion has a biological component (including genet-
ic links and biochemical imbalances), a psycho-
logical component (including how people think,
feel, and behave), and a social component (includ-
ing family and societal pressures and cultural fac-
tors). Individual theories have tended to empha-
size one or the other of these components. The
main theories of depression are biological and
cognitive in nature, although there are also
psychodynamic and behavioral explanations which
are discussed below.Psychodynamic Theories of Depression. The
psychological study of depression was essentially
begun by Sigmund Freud and Karl Abraham, a
German physician. Both described depression as a
complex reaction to the loss of a loved person or
thing. This loss could be real or imagined, through
death, separation, or rejection. For Abraham (1911/
1968), individuals who are vulnerable to depres-
sion experience a marked ambivalence toward
people, with positive and negative feelings alter-
nating and blocking the expression of the other.
These feelings were seen to be the result of early
and repeated disappointments. Depression, or mel-
ancholy, as Freud called it, was grief out of control
(Freud 1917/1957). Unlike those in mourning,
however, depressed persons appeared to be more
self-denigrating and lacking self-esteem. Freud theo-
rized that the anger and disappointment that had
previously been directed toward the lost person or
thing was internalized, leading to a loss of self-
esteem and a tendency to engage in self-criticism.
Theorists who used a similar approach and modi-
fied Freud’s theories for depression were Sandot
Rado and Melanie Klein, and most recently John
Bowlby (1988).Behavioral Theories of Depression. In con-
trast to a focus on early-childhood experiences and
internal psychological processes, behavioral theo-
ries attempt to explain depression in terms of
responses to stimuli and the overgeneralization of
these responses. For example, loss of interest to a
wide range of activities (food, sex, etc.) in response
to a specific situation (e.g., loss of a job). The basic
idea is that if a behavior is followed or accompa-
nied by something good (a reward), the behavior
will increase and persist. If the reward is taken
away, lessened, or worse still, if the behavior is
punished, the behavior will lessen or disappear. B.
F. Skinner, a key figure in the behaviorist move-
ment, postulated that depression was the result of
a weakening of behavior due to the interruption of
an established sequence of behavior that had been
positively reinforced by the social environment.
For example, the loss of a job would stop a lot of
the activities that having a salary provides (e.g.,
dining out often, entertainment). Most behavioral
theories extended this idea, focusing on specific