Abnormal Psychology

Researching Abnormality 169

Research Challenges in Understanding

Abnormality

Let’s examine your hypothesis about the relationship between experiencing a

childhood loss and feeling depressed after a breakup in adulthood. How can we use

the neuropsychosocial approach to understand why breaking up can lead some peo-

ple to become depressed? We could investigate neurological mechanisms by which

early loss, associated with helplessness, might make people more vulnerable to later

depression, perhaps through enduring changes to brain structure or function. We

could investigate psychological effects resulting from early loss, such as learned

helplessness, cognitive distortions, or problems with emotional regulation. We could

investigate social mechanisms, such as the way the loss altered subsequent attach-

ments to and relationships with others or how economic hardships arising from the

early loss created a higher baseline of daily stress. And, crucially, we could propose

ways in which these possible factors might interact with one another. For exam-

ple, perhaps daily fi nancial stress not only increases the degree of worrying about

money, but also such worrying in turn changes neurological functioning as well as

social functioning (as preoccupying fi nancial worries alter social interactions).

Whatever type of factors researchers investigate, each type comes with its own

challenges, which affect the way a study is undertaken and which limit the conclu-

sions that can be drawn from a study’s results. Let’s examine the major types of

challenges to research on the nature and causes of abnormality from the neuropsy-

chosocial perspective.

Challenges in Researching Neurological Factors

DSM-IV-TR does not consider neurological factors when assigning diagnoses, but

many researchers are exploring the possible role of neurological factors in causing

psychological disorders. This research is yielding new insights into why some of us, in

some circumstances, develop psychological problems. In fact, current fi ndings about

neurological factors are coming to play an increasingly large role in treatment.

With the exception of genetics, almost all techniques that assess neurological fac-

tors identify abnormalities in the structure or function of the brain. Thisassessment is

done directly (e.g., with neuroimaging) or indirectly (e.g., with neuro psychological test-

ing or measurements of the level of stress hormones in the bloodstream). Such abnor-

malities are associated (correlated) with specifi c disorders or symptoms. For instance,

people with schizophrenia have larger than normal ventricles (the fl uid- containing

cavities in the brain) and other areas of the brain are correspondingly smaller

(Vita et al., 2006). Like all correlational studies, the studies that revealed the enlarged

ventricles cannot establish causation. That is, these results cannot establish whether:

• schizophrenia arises because of the effects of this brain abnormality;


• episodes of psychosis somehow create larger ventricles (in essence, schizophrenia,

over time, creates the brain abnormality);

• the brain abnormality existed before symptoms of schizophrenia developed; or


• the brain abnormality arises from some other factor, such as the effects of medica-

tions for schizophrenia. (We will revisit these possible causes in Chapter 12, when

we discuss schizophrenia in more detail.)

Another limitation of research using neuroimaging is that we do not yet have a

complete understanding of what different parts of the brain do. Thus, researchers

cannot be sure about the implications of structural abnormalities (e.g., enlarged ven-

tricles) or functional abnormalities (e.g., why specifi c areas that are normally activated

during a task are not activated when a person with a particular disorder performs the

task). For example, the parietal lobes are involved in attention, in representing spatial

information, in performing arithmetic, and in many other activities; simply knowing