The Big Picture: Chapter Overview

About one-third of those who participated in a national survey said that they had experienced one or more psychological disorders in their lifetime. Twenty percent reported that they currently had an active disorder. Abnormal behavior is defined differently depending on the context; for example, in legal institutions insanity is a term used to refer a person's inability to understand the nature and quality or wrongfulness of his or her acts. From psychology's point of view, if the behavior is deviant, maladaptive, and/or personally distressing, it is considered abnormal behavior. The explanations for abnormal behavior come from various perspectives, including biological, psychological, and sociocultural.

The biological approach explains psychological disorders in terms of internal and organic causes. For example, the medical model describes mental disorders as medical disorders with a biological origin. Biological explanations may be structural (e.g., problems in brain structures), biochemical (e.g., neurotransmitter imbalance), or genetic (e.g., presence of certain genetic markers associated with psychological disorders). The psychological approach is founded on the main psychological perspectives: psychodynamic, behavioral and social cognitive, and humanistic. From the psychodynamic point of view, psychological disorders are caused by unconscious conflicts. Behavioral and social cognitive psychologists argue that psychological disorders stem from rewards and punishments in the environment that promote the abnormal behaviors. The humanistic perspective focuses on factors that may limit a person's ability to fulfill his or her potential as the causes of psychological disorders. The sociocultural approach considers broader contextual variables that may contribute to psychological disorders, such as culture, socioeconomic background, and gender socialization. The interactionist or biopsychosocial approach suggests that the causes of normal as well as abnormal behaviors are a combination of biological, psychological, and sociocultural factors.

The DSM is a widely used system for classifying mental disorders published by the American Psychiatric Association. The most recent version, the DSM-IV-TR (published in 2000), is a text revision of the 1994 DSM-IV that included descriptions for over 200 specific disorders. The DSM-IV uses a multiaxial system, consisting of five dimensions used to assess individuals. Critics charge the DSM-IV with focusing too much on the medical model, categorizing everyday problems as mental disorders, and overemphasizing problems or pathology. A study by Rosenhan illustrated the danger of overemphasizing pathology in diagnosis, as eight normal college students instructed to present an incomplete pattern of abnormal behavior were diagnosed with schizophrenia and hospitalized from 3 to 52 days.

Motor tension, hyperactivity, and apprehensive expectations and thoughts characterize anxiety disorders. Generalized anxiety disorder consists of persistent anxiety for at least one month without specific symptoms. Etiology refers to the investigation of the causes or significant antecedents of a mental disorder. The etiology of generalized anxiety disorders includes genetic predispositions and life stressors. Panic disorder involves recurrent and sudden onset of apprehension or terror and may include agoraphobia, a fear of being in public and being unable to escape or to get help if incapacitated. Phobic disorders involve an irrational, overwhelming, persistent fear of an object or a situation. An example is social phobia, an intense fear of being humiliated or embarrassed in public. Obsessive-compulsive disorder is a mental disorder characterized by obsessions (anxiety-provoking thoughts that won't go away) and compulsions (ritualistic behaviors performed in a stereotyped way). The most common compulsions include checking, cleaning, and counting. Post-traumatic stress disorder (PTSD) is an anxiety disorder that develops through exposure to a traumatic event such as combat, war-related traumas, sexual abuse, assault, or a catastrophic incident. The symptoms of PTSD include flashbacks, emotional numbness, excessive arousal, problems with memory and concentration, feelings of apprehension, and impulsivity. PTSD involves a course of increased symptoms followed by remission or decrease of symptoms; however, this disorder is characterized by the vivid quality of the flashback experiences, which can be triggered by ordinary events that serve as reminders of the traumatic event.

Dissociative disorders involve a sudden memory loss or change of identity. The concept of hidden observer, developed to study hypnosis, has been theoretically associated with dissociative disorders. Dissociative amnesia is memory loss due to extensive psychological stress. Dissociative fugue is amnesia in addition to unexpected travel away from home and the assumption of a new identity. The most dramatic but rare dissociative disorder is dissociative identity disorder; an individual with this disorder has two or more distinct personalities or selves, each having its own memories, behaviors, and relationships. Many individuals with dissociative identity disorder have histories of sexual or physical abuse during early childhood.

Mood disorders include depressive disorders and bipolar disorder. Major depressive disorder is a severe form of depression that involves experiencing unhappiness, fatigue, problems in thinking, and other symptoms for at least two weeks or longer. Another depressive disorder is dysthymic disorder, which tends to be longer-lasting with fewer and less severe symptoms than major depressive disorder. Bipolar depression is characterized by dramatic mood swings that include mania and depression. Biological explanations of mood disorders focus on heredity, brain processes, and neurotransmitter deregulation. Individuals with severe major depressive disorder show a decreased metabolic activity in the cerebral cortex and depressed individuals experience less of the deep resting sleep. Psychosocial factors have also been suggested as causes of mood disorders. Freud described depression as the turning inward of aggressive instincts. Psychologists from the behavioral perspective argue that depression can be a result of learned helplessness. Depressed individuals have been found to resort to a ruminative coping style, which involves focusing on the sadness and hopelessness of their circumstances. From the cognitive perspective, Beck suggests negative thoughts are the cause of depression. The attributional view of learned helplessness argues that optimistic thinking protects against depression while pessimistic thinking contributes to depression. Another approach to understating depression, depressive realism, argues that people with the disorder are simply too realistic. Supporting this view is the observation that people without depression tend to overestimate the extent to which they can control things in their life. Among the sociocultural factors, according to Bowlby, is the attachment experience of the person. Bowlby suggests that insecure attachment between child and mother plays a role in depression. Individuals living in poverty are more likely to develop depression that individuals in higher socioeconomic status. It has also been argued that the fact that depression is more common and intense in some cultures supports the view that sociocultural factors play a role in this disorder. Another sociocultural factor, gender, has been associated with depression, as women are twice as likely as men to develop depression. Experiencing severe depression or other psychological disorders could prompt a person to consider suicide. Statistics indicate that women are more likely to threaten suicide but men are more likely to commit suicide. Suicide runs in families, suggesting a genetic factor. High stress and trauma have also been associated with suicide, as have cultural patterns and sociocultural factors such as economic hardship.

Distorted thoughts and perceptions, odd communication, inappropriate emotion, abnormal motor behavior, and social withdrawal characterize the schizophrenic disorders. Many schizophrenics have delusions and hallucinations. Disorganized schizophrenia consists of delusions and hallucinations that have little or no recognized meaning. In catatonic schizophrenia, the individual engages in bizarre motor behavior, such as being in a completely immobile stupor. Paranoid schizophrenia is characterized by delusions of reference, grandeur, and persecution. In undifferentiated schizophrenia, the symptoms don't meet the criteria for the other types or they meet the criteria for more than one type. Genetic factors have been examined as important in schizophrenia, with the disorder running in families. Imbalances in brain chemistry and distorted cerebral blood flow may also be related to schizophrenia. The diathesis-stress view emphasizes a combination of genetic predisposition and environmental stress as causes of schizophrenia.

Personality disorders are chronic, maladaptive cognitive-behavioral patterns that are thoroughly integrated into the individual's personality. These disorders are grouped into three clusters: odd/eccentric, dramatic/emotionally problematic, and chronic-fearfulness/avoidant. The odd/eccentric cluster includes the paranoid, schizoid, and schizotypal personality disorders. The dramatic/emotionally problematic cluster includes histrionic, narcissistic, borderline, and antisocial personality disorders. The antisocial personality disorder has been associated with violent crimes and is much more common in males than females. Biological, psychological, and sociocultural factors contribute to the understanding of the antisocial personality disorder. Finally, the chronic-fearfulness/avoidant cluster includes the avoidant, dependent, passive-aggressive, and obsessive-compulsive personality disorders.