Criteria for defining psychological disorders depend on whether cultural
norms are violated, whether behavior is maladaptive or harmful, and whether
there is distress.
The medical model describes and explains psychological
disorders as if they are diseases.
The vulnerability-stress model states that disorders are
caused by an interaction between biological and environmental factors.
The learning model theorizes that psychological disorders
result from the reinforcement of abnormal behavior.
The psychodynamic model states that psychological disorders
result from maladaptive defenses against unconscious conflicts.
Psychologists use objective and projective tests
to assess psychological disorders.
Classification
Classification allows psychologists to describe disorders,
predict outcomes, consider treatments, and study etiology.
Insanity is a legal term, not a diagnostic label.
Psychologists and psychiatrists use the DSM to diagnose psychological disorders.
The DSM uses a multi-axial system of
classification.
The DSM is a useful tool but has been criticized for
several reasons.
Most of the major disorders in the DSM are found
worldwide.
Culture-bound syndromes are limited to specific cultural
contexts.
Anxiety Disorders
A chronic, high level of anxiety may be a sign of an anxiety
disorder.
Generalized anxiety disorder involves persistent and
excessive anxiety for at least six months.
Having a specific phobia means becoming anxious when exposed
to a specific circumstance.
Social phobia is characterized by anxiety in social or
performance situations.
A person with panic disorder experiences recurrent,
unexpected panic attacks.
Agoraphobia involves anxiety about having panic attacks in
difficult or embarrassing situations.
Obsessive-compulsive disorder entails
obsessions, compulsions, or both.
Post–traumatic stress disorder is a set of psychological and
physiological responses to a highly traumatic event.
Biological factors implicated in the onset of anxiety disorders include
genes, different sensitivity to anxiety, the
neurotransmitters GABA and serotonin, and brain damage.
Conditioning and learning may contribute to the development of phobias.
Some styles of thinking may make people more susceptible to anxiety
disorders.
Neuroticism is associated with anxiety disorders.
Mood Disorders
Mood disorders are characterized by marked disturbances in
emotional state, which cause physical symptoms and affect thinking, social
relationships, and behavior.
Mood disorders may be unipolar or bipolar.
People with dysthymic disorder have depressed mood for at
least two years.
Major depressive disorder involves at least one period with
significant depressive symptoms.
Bipolar disorders involve at least one period with manic
symptoms and usually depressive periods as well.
Biological influences on mood disorders include genes,
the neurotransmitters norepinephrine and serotonin, and
brain abnormalities.
There is a two-way relationship between negative thinking and depression.
Cognitive characteristics of depressed people include learned
helplessness; a pessimistic worldview;
hopelessness; a tendency to make internal, stable, global
attributions; and a tendency to ruminate.
There is a two-way relationship between social support and depression.
Depression may be related to experiences of loss.
The onset and course of mood disorders may be influenced by
stress.
Eating Disorders
Eating disorders are characterized by problematic eating
patterns, concerns about body weight, and inappropriate efforts to control
weight.
Anorexia nervosa entails very low body weight, fear of
gaining weight, and distorted body image.
Bulimia nervosa involves binge eating and unhealthy efforts
to control body weight.
Some people may have a genetic vulnerability to eating disorders.
Eating disorders may be associated with particular personality traits.
Cultural factors strongly influence the onset of eating disorders.
Lacking autonomy in the family and having an overly weight-conscious
mother may influence the onset of eating disorders.
People with eating disorders tend to have certain distortions of thinking.
The onset of anorexia nervosa may be associated with stressful events.
Somatoform Disorders
Somatoform disorders are characterized by real physical
symptoms that cannot be fully explained by a medical condition, the effects of a
drug, or another mental disorder.
A person with somatization disorder has many different,
recurrent physical symptoms.
Conversion disorder involves symptoms that affect voluntary
motor functioning or sensory functioning.
People with hypochondriasis constantly fear that they may
have a serious disease.
People with histrionic personality traits may be more likely
to develop somatoform disorders.
Several cognitive factors may contribute to somatoform disorders.
People with somatoform disorders may learn to adopt a sick role.
Substance-Related Disorders
Many substance-related disorders are described in the
DSM.
Substance abuse is a maladaptive pattern of drug use that
results in repeated, negative legal, social, occupational, or academic
consequences.
Substance dependence involves continuing to use a drug
despite persistent harmful physical or psychological consequences.
The disease model of addiction holds that addiction is a
disease that must be treated medically.
The learning model of addiction holds that addiction is a way
of coping with stress.
Genes may produce a predisposition to substance dependence.
Several lines of evidence suggest that environmental factors play a key
role in substance dependence.
Schizophrenia
Schizophrenia is a psychotic disorder that includes
positive and negativesymptoms. There are several subtypes of schizophrenia.
The paranoid type is characterized by marked
delusions or hallucinations and relatively normal
cognitive and emotional functioning.
The disorganized type involves disorganized behavior,
disorganized speech, and emotional flatness or inappropriateness.
The catatonic type is characterized by unnatural
movement or speech patterns.
A diagnosis of undifferentiated type applies if
diagnostic criteria are not met for any of the above three subtypes.
Research suggests that genes, neurotransmitters,
and brain abnormalities are involved in the onset of schizophrenia.
Stress may help to induce schizophrenia in people who are already
biologically vulnerable to the disorder.
Dissociative Disorders
Dissociative disorders are characterized by disturbances in
consciousness, memory, identity, and perception.
Dissociative fugue involves sudden and unexpected travel away
from home, failure to remember the past, and confusion about identity.
People with dissociative identity disorder fail to remember
important personal information and have two or more identities or personality
states that control behavior.
Dissociative identity disorder is a controversial diagnosis. Psychologists
disagree about why its prevalence has risen since the 1980s.
Severe stress may play a role in the onset of dissociative
disorders.
Personality Disorders
Personality disorders are stable patterns of
experience and behavior that differ noticeably from patterns that are
considered normal by a person’s culture.
People with schizoid personality disorder are socially
withdrawn and have restricted expression of emotions.
Borderline personality disorder involves impulsive behavior
and unstable relationships, emotions, and self-image.
Histrionic personality disorder is characterized by
attention-seeking behavior and shallow emotions.
People with narcissistic personality disorder have an
exaggerated sense of importance, a strong desire to be admired, and a lack of
empathy.
Avoidant personality disorder involves social withdrawal, low
self-esteem, and extreme sensitivity to being evaluated negatively.
Antisocial personality disorder begins at age fifteen and
includes a lack of respect for other people’s rights, feelings, and needs.
Abnormalities in physiological arousal, a genetically
inherited inability to control impulses, and brain
damage may be involved in the development of antisocial personality
disorder.
Environmental influences are also likely to influence the development of
antisocial personality disorder.