208 CHAPTER 6
P SNP SNNote also that biological differences—such as specifi c female hormonal changes
involved in puberty—may contribute to this gender difference (Halbreich & Kahn,
2001; Steiner, Dunn, & Born, 2003). A role for this biological factor is consistent
with the fi nding that, before puberty, boys and girls have similar rates of depres-
sion (Cohen et al., 1993). Additional evidence that hormones infl uence depression
is the fact that women and men have similar rates of the disorder after women have
reached menopause (and hence their levels of female hormone are greatly reduced;
Hyde, Mezulis, & Abramson, 2008).
The different explanations for the gender difference are not mutually exclusive,
and these factors may interact with one another (Hyde, Mezulis, & Abramson,
2008). For instance, girls who enter puberty early are more likely to become
depressed (Kaltiala-Heino, Kosunen, & Rimpela, 2003), perhaps in part because
their early physical development makes them more likely to be noticed and teased
about their changing bodies, which in turn can lead to dissatisfaction with and
rumination about their bodies. Let’s examine more broadly how feedback loops
contribute to depression.FEEDBACK LOOPS IN ACTION: Depressive Disorders
How do neurological, psychological, and social factors interact through feedback
loops to produce depression? As we noted earlier in the section on genetics, some
people are more vulnerable to stress. For these people, the HPA axis is highly
responsive to stress (and often the stress is related to social factors). For example,
abuse or neglect at an early age, with accompanying frequent or chronic increase
in the activity of the HPA axis, can lead cortisol-releasing cells to overrespond
to any stressor—even mild ones (Nemeroff, 1998). In fact, college students with
a history of MDD reported feeling more tension and responded less well after a
stressful cognitive task (one that, unknown to these participants, was impossible
to solve) than college students with no history of MDD (Ilgen & Hutchison,
2005). These results support the notion that stressors affect people vulnerable
to MDD differently than they affect those without such a vulnerability (Hasler
et al., 2004).
A cognitive factor that makes a person vulnerable to depression, such as a
negative attributional style, a ruminative coping style, or dysfunctional thoughts
(all psychological factors), can amplify the negative effects
of a stressor. In fact, such cognitive factors can lead peo-
ple to be hypervigilant for stressors or to interpret neutral
events as stressors, which in turn activates the HPA axis.
This neurological response then can lead such individuals
to interact differently with others (social factor)—making
less eye contact, being less responsive, and becoming more
withdrawn.
Researchers have identifi ed other ways that neurologi-
cal, psychological, and social factors create feedback loops
in depression. According to James Coyne’s interactional the-
ory of depression (Coyne, 1976; Coyne & Downey, 1991;
Joiner, Coyne, & Blalock, 1999), someone who is neurologi-
cally vulnerable to depression (perhaps because of genes or
neurotransmitter abnormalities) may, through verbal and
nonverbal behaviors (psychological factor), alienate people
who would otherwise be supportive (social factor; Nolan &
Mineka, 1997). Such behaviors could arise from negative
attributions and views about self and the environment (psychological factors),
which in turn could arise from group interactions (social factors), such as being
teased or ridiculed, or modeling the behavior of someone else. When someone
who is depressed expresses consistently negative attitudes, exhibits a pattern of
ignoring or failing to benefi t from the help of others, or seems to become tooGirls are typically encouraged to cope with stres-
sors by ruminating. In contrast, boys are typically
encouraged to use activity and distraction. This
gender difference may contribute to the higher
rate of depression among women than among
men (Nolen-Hoeksema, 1987, 2001).Image Source/Jupiterimages