Abnormal Psychology

The History of Abnormal Psychology 27

everybody experiences the same social factor in the same way. And what’s important

is not simply the objective circumstance; it’s how a person perceives it. For example,

think about roller coasters: For one person, they are great fun; for another, they are

terrifying. Similarly, Big Edie and Little Edie didn’t appear to mind their isolation

and strange lifestyle and may even have enjoyed it; other people, however, might fi nd

living in such circumstances extremely stressful and depressing. Whether because of

learning, biology, or an interaction between them, some people are more likely to

perceive particular events and stimuli as stressors (and therefore to experience more

stress) than others. The diathesis–stress model was the fi rst approach that integrated

existing, but separate, explanations for psychological disorders.

The Biopsychosocial and Neuropsychosocial Approaches

To understand the bases of both diatheses and stress, we need to look more care-

fully at the factors that underlie psychological disorders.

Three Types of Factors

Historically, researchers and clinicians grouped the factors that give rise to psycho-

logical disorders into three general types: biological (including genetics, the structure

and function of the brain, and the function of other bodily systems); psychological

(thoughts, feelings, and behaviors); and, social (social interactions and the environment

in which they occur). The biopsychosocial approach to understanding psychological

disorders rests on identifying these three types of factors and docu-

menting the ways in which each of them contributes to a disorder.

That is, the biopsychosocial approach leads researchers

and clinicians to look for ways in which the three

types of factors contribute to both the diath-

esis (the predisposition) and the stress. For

instance, having certain genes (a biological

factor), having biases to perceive certain situations

as stressful (a psychological factor), and living in

poverty (a social factor) all can contribute to

a diathesis; similarly, chronic lack of sleep (a

biological factor), feeling that one’s job is over-

whelming (a psychological factor), or having

a spouse who is abusive (a social factor) can

contribute to stress.

However, two problems with the tradi-

tional biopsychosocial approach have become

clear. First, the approach does not specifi cally

focus on the organ that is responsible for cognition and affect, that allows us to learn,

that guides behavior, and that underlies all conscious experience—namely, the brain.

The brain not only gives rise to thoughts, feelings, and behaviors, but also mediates all

other biological factors; it both registers events in the body and affects bodily events.

Second, sometimes the biopsychosocial approach was used to identify a set of

factors that together caused a disorder. However, the factors were often considered in

isolation, as if they were items on a list. Considering the factors in isolation is remi-

niscent of the classic South Asian tale about a group of blind men feeling different

parts of an elephant, each trying to determine what the animal is. One person feels the

trunk, another the legs, another the tusks, and so on, and each reaches a different

conclusion. Even if you combined all the people’s separate reports, you might miss the

big picture of what an elephant is: That is, an elephant is more than a sum of its body

parts; the parts come together to make a dynamic and wondrous creature.

We are beginning to understand how the three types of factors combine and af-

fect each other. That is, factors that researchers previously considered to be indepen-

dent are now known to infl uence each other. For example, the way that parents treat

their infant was historically considered to be exclusively a social factor—the infant

was a receptacle for the caregiver’s style of parenting. However, more recent research

has revealed that parenting style is in fact a complex set of interactions between

Diathesis–stress model

The model that proposes that a psychological

disorder is triggered when a person

with a predisposition—a diathesis—for

the particular disorder experiences an

environmental event that causes signifi cant

stress.

Biopsychosocial approach

The view that a psychological disorder arises

from the combined infl uences of three types of

factors—biological, psychological, and social.

It’s a snake!

It’s a spear!

It’s a fan!

It’s a wall!

It’s a tree!

It’s a rope!

The whole elephant cannot be described by a

group of blind men if each of them is feeling only

a small part of the animal’s body. In the same

way, past explanations of psychological disorders

that focused on only one or two factors created an

incomplete understanding of such disorders.