Psychological Disorders and Their Treatment

The three Ds are a screen rather than a formula. A behavior that is unusual but causes no impairment and no distress is not a disorder, and a behavior that is common in a culture is not deviant within it. That is why exam scenarios so often include a line about how well the person is functioning at work or at home: it is telling you whether the dysfunction criterion is met.

Diathesis-stress is the answer whenever a question asks how genetics and environment jointly produce a disorder. Picture a load-bearing beam with a hairline crack. The crack alone holds fine, and an ordinary load on an intact beam is fine; the failure requires both. This is also why concordance in identical twins is high but well below one hundred percent, a statistic the exam likes.

For positive and negative symptoms, drop the everyday meaning of the words entirely and read them as plus and minus. A hallucination is an experience the person has that others do not — added. Flat affect is expression the person no longer produces — subtracted. Nothing about either word signals whether the symptom is good or bad.

Treatment families are easiest to hold by what each one thinks the problem is. Psychodynamic therapy thinks the problem is buried conflict, so it works to bring it to awareness. Behavior therapy thinks the problem is a learned response, so it retrains the response and ignores insight. Cognitive therapy thinks the problem is the interpretation, so it tests and revises the thought. Humanistic therapy thinks the problem is a blocked capacity for growth, so it supplies acceptance and lets the client lead. Biomedical treatment thinks the problem is neurochemical, so it changes the chemistry.

Definition comes first. Psychologists generally treat a pattern as disordered when it is dysfunctional — it interferes with everyday life — when it causes distress to the person, and when it departs markedly from what the person's culture expects. Wakefield's harmful dysfunction account tightens this by requiring both an internal mechanism that is not doing its job and harm judged by the standards of the person's culture. Two consequences are frequently tested: the same behavior can be disordered in one context and not in another, and rarity alone never establishes disorder.

Classification is the DSM's job. The manual assigns disorders to categories, specifies the criteria a clinician must observe, and is revised as evidence changes; ETS states that its Psychology Test follows the terminology, criteria, and classifications of the current text revision of the fifth edition. Two features of classification matter for items: comorbidity, in which one person meets criteria for more than one disorder simultaneously, is common rather than exceptional; and a classification system describes and organizes symptoms rather than explaining their causes.

Explanation is where the diathesis-stress model does the work. A predisposition — genetic, biological, or psychological — is the diathesis, and life events supply the stress; the disorder appears when both are present in sufficient measure. This model is why family and twin studies show elevated but partial risk, and why the same stressor produces disorder in one person and not another. It also frames the biological and psychological perspectives as complementary rather than competing.

The category most often tested in detail is schizophrenia, because it has a clean symptom split. Positive symptoms are additions to ordinary experience: hallucinations, most often auditory; delusions, which are fixed false beliefs held despite contrary evidence; and disorganized thinking, which surfaces as speech that derails from one topic to another. Negative symptoms are subtractions: blunted or flat affect, sharply reduced speech, and avolition, the loss of motivation for goal-directed activity. Beyond schizophrenia, know the headline distinction inside each major grouping — generalized anxiety versus panic disorder versus specific phobia in the anxiety group; obsessions as intrusive thoughts versus compulsions as the repetitive acts that relieve them; major depressive disorder versus bipolar disorder, which requires a manic episode; and post-traumatic stress disorder as a trauma- and stressor-related condition rather than an anxiety disorder in the current manual.

Treatment closes the loop. Psychoanalysis and psychodynamic therapy aim to make unconscious conflict conscious, using techniques such as free association and interpretation of resistance and transference. Behavior therapy applies conditioning directly: systematic desensitization pairs relaxation with a graded fear hierarchy, aversive conditioning attaches an unpleasant response to an unwanted behavior, and token economies apply operant reinforcement. Cognitive therapy targets the interpretation rather than the event, and cognitive-behavioral therapy combines thought restructuring with behavioral practice; it is the family most often described in outcome research for anxiety and depression. Humanistic client-centered therapy, associated with Rogers, is non-directive and rests on unconditional positive regard, genuineness, and empathy. Biomedical treatment uses antidepressant, anxiolytic, antipsychotic, and mood-stabilizing medication, and the exam expects you to separate a medication's side effects, such as the involuntary movements of tardive dyskinesia, from symptoms of the disorder itself.