Psychopathology, or mental illness, is illness that is revealed in impaired behavioral or psychological functioning or both. The term refers to a broad range of syndromes that involve abnormalities in sensations, cognition, and emotional states. A working assumption in the field is that psychopathological syndromes, or groups of symptoms, are not merely predictable responses to a specific stressful event--for instance, the death of a loved one--but rather a manifestation of a psychological or a biological dysfunction in the person. Psychopathologies range from relatively mild disorders, such as dysthymia (a form of \Tdepression\t), to serious disorders that involve pervasive disability, such as schizophrenic disorders (see \Tschizophrenia\t). Although the precise cause of most forms of psychopathology are still unknown, significant progress has been made in the diagnosis and treatment of these illnesses. MODERN CLASSIFICATION The primary diagnostic system used in the United States today--and imitated in many other countries--is the \TDiagnostic and Statistical Manual of Mental Disorders\t (DSM), a publication of the American Psychiatric Association. The first DSM was published in 1952, and it has been revised and expanded three times--in 1968 (DSM-II), 1979 (DSM-III), and 1987 (DSM-III-R). The manual is important to researchers because it provides the research community a common language with which to communicate about mental disorders. The manual also aids in treatment planning in that it provides therapists a tool with which to diagnose patients expediently. Therapists using the DSM-III-R employ several diagnostic criteria--such as psychological stress factors and an assessment of functional skills--in addition to delineating the various symptoms of each disorder. This is done because the presence of just one sign or symptom in a patient is not enough to form a firm diagnosis. In addition, more than one disorder may be present in a person. Extensive information is gathered in an interview with the patient and is augmented through \Tpsychological measurement\t, a physical examination, and interviews with family members. Listed below are the major categories of psychopathology contained in DSM-III-R. Schizophrenic Disorders These disorders are characterized by the presence of psychotic symptoms (see \Tpsychosis\t) during active, or heightened, episodes of the illness. Delusions, hallucinations, certain abnormalities in emotional expression, and thought disorder are among the primary defining features of schizophrenia. There are several diagnostic subtypes of the disorder. Disorganized schizophrenia is defined by the predominance of such symptoms as incoherent speech, inappropriate emotional reactions, and disorganized behavior. Catatonic schizophrenia is typically characterized by an extreme decrease in motor activity, often accompanied by muteness. Patients with paranoid schizophrenia manifest delusions of a persecutory nature and, frequently, auditory hallucinations. In undifferentiated schizophrenia there is a mixture of symptoms, including distinct delusions and hallucinations along with disorganized behavior. Dissociative Disorders These disorders involve a disruption of the patient's normal personality due to alterations in consciousness, identity, or memory for personal experience. The most common type of dissociative disorder is psychogenic \Tamnesia\t, which involves a total loss of memory for events associated with a traumatic experience. In the disorder known as psychogenic fugue, the individual loses all awareness of his or her own identity. While both amnesia and fugue states are predominantly manifested in the patient's thinking, multiple personality disorder (see \Tpersonality, multiple\t) involves more pervasive behavioral changes. The person's personality fragments into two or more independent personalities, each with its own distinct way of perceiving, relating to, and thinking about the environment and the self. Anxiety Disorders These disorders include illnesses in which there is debilitating tension, \Tanxiety\t, and avoidance. Typically, the anxiety is not based upon present circumstances, but rather upon actual or fantasized experiences from the past or in the future. The way in which a person manifests excessive anxiety determines the specific type of diagnosis rendered. In phobic disorders (see \Tphobia\t) there is a specific source of anxiety, and negative feelings are controlled by the patient's efforts to avoid the feared object or situation. Another form of anxiety disorder is the panic attack--the sudden, overpowering feeling of terror that is experienced by about 1.5% of the population at some time in their lives. In contrast to the abrupt onset and dispersal of a panic attack is the constant state of tension associated with generalized anxiety disorders. \Lobsessive-compulsive disorder\ls involve recurrent, unpleasant thoughts or repetitive behaviors, or both, that are presumed to reflect the patient's attempts to control anxiety. Affective Disorders These disorders are characterized by mood disturbances, and they generally occur when normal human emotions reach extremes. The affective disorders can be mild or severe and sometimes require hospitalization. Similarly, the recovery rate for affected disorders varies from a few months to several years following an episode. One of the most common affective disorders is dysthymia, which involves long-standing (at least two years in duration) symptoms of depressed mood, disturbances in eating and sleeping, decreased energy, and feelings of hopelessness and low self-esteem. Major depressive disorder is characterized by these same symptoms, but typically of a more intense nature and with a shorter duration. People with bipolar affective disorder experience periods of depression as well as periods of mania, or extreme mood elevations. During manic episodes the individual may show high levels of activity, talkativeness, and elation. Psychosexual Disorders These are disorders of sexual behavior in which psychological factors seem to be at the root of the problem. There are two general classes of psychosexual disorders: paraphilias and sexual dysfunctions. The essential feature of the paraphilias is an intense and recurrent sexual urge involving nonhuman objects, or the suffering of oneself or one's sexual partner, or of children or other nonconsenting persons. Transsexualism (see \Tsex reassignment\t), \Texhibitionism\t, pedophilia, \Tfetishism\t, sado-masochism, and \Tvoyeurism\t) are among the most frequently diagnosed paraphilias. Transsexuals experience an incongruity between their biological sex and their subjective sense of gender identity. Individuals with a diagnosis of exhibitionism suffer from extreme urges to expose their genitals in inappropriate places. Pedophilia is characterized by sexual fantasies about, or sexual acts with, prepubescent children. Fetishism is a preference for the use of nonliving objects as the method of achieving sexual excitement. Sado-masochism is a preference for receiving and inflicting pain during sexual activity. A diagnosis of exhibitionism, voyeurism, or pedophilia does not require that a person act on his or her impulses, but only that the abnormal sexual impulses are disturbing to the patient. The sexual dysfunctions involve abnormalities in sexual appetite or psychophysiologic changes that characterize the complete sexual-response cycle. Included among these dysfunctions are premature ejaculation, male erectile disorder, and inhibited female orgasm. Somatoform Disorders These disorders involve physical symptoms that do not have demonstrable organic bases. There are two general types of somatoform disorders: those which are characterized by excessive concerns about physical conditions but are associated with no specific symptom, and those in which there is one or more identifiable physical symptom. Hypochondriasis (see \Thypochondria\t), or exaggerated concerns and unrealistic fears about one's health, fall into the first group. Also included in this group is body dysmorphic disorder, which is characterized by a preoccupation with some imagined defect in physical appearance. Conversion disorders constitute the second group of somatoform disorders. They involve actual physical disabilities without any physical basis. These disorders are typically easy to separate from organically based problems because the physical symptom usually appears suddenly during a period of extreme psychological distress and often tends to be psychologically symbolic, as when a person develops paralysis in a subconscious effort to avoid unpleasant situations. Organic Mental Disorders These disorders include mental disturbances in which intellectual functioning, emotional functioning, or both are impaired through an abnormality in brain functioning that can be impaired through an abnormality in brain functioning that can be either transient or permanent; they may be caused by injury, disease, the aging process, or drug abuse. \Tdelirium\t is an acute, temporary state of mental confusion, often accompanied by hallucinations and delusions. Dementia is a more permanent deterioration of intellectual functioning and behavioral capacities. This mental disorder is frequently caused by \TAlzheimer's disease\t, a degenerative disorder of the central nervous system. Personality Disorders These disorders entail inflexible, maladaptive personality traits that cause functional impairment or inner distress. These traits are presumed to be characteristic of a person's functioning since early adulthood. DSM-II-R classifies personality disorders into three groups. The first group includes paranoid, schizoid, and schizotypal personality disorders. In all of these disorders the patient appears excessively odd or eccentric to others. In addition, patients with paranoid personality disorder (see \Tparanoia\t) show unwarranted suspicion, jealousy, and anger and, as a result, have recurring interpersonal conflicts. Schizoid personality disorder is characterized by marked indifference to social relationships and a restricted range of emotional expression. Essential features of schizotypal personality disorder are peculiarities of thought and behavior, and deficits in social skills. The abnormalities in the thoughts of schizotypal patients include paranoid tendencies and bizarre fantasies (such as a belief that others can read one's thoughts). These abnormalities, however, are much less severe and debilitating than those shown by patients with the similarly named schizophrenic disorders. The second group comprises the antisocial, borderline, histrionic, and narcissistic personality disorders. Symptoms of these disorders can include dramatic, emotional, and erratic behaviors. Persons with antisocial personality disorder display a pattern of irresponsible, aggressive, and nonconformist behavior that extends from adolescence through adulthood. This disorder is more common in males than in females. In contrast, borderline personality disorder occurs more often in women and is characterized by emotional instability, confusions about identity, and unstable interpersonal relationships. Histrionic personality disorder involves a pervasive pattern of excessive emotionality and attention seeking. A preoccupation with the self and a lack of empathy for others are the chief features of narcissistic personality disorder. The third class of personality disorders involves predominant symptoms of anxiety and fearfulness. These include avoidant, dependent, obsessive-compulsive, and passive-aggressive personality disorders. In avoidant personality disorder the individual shows extreme shyness and fear of being negatively evaluated by others. Submissiveness and a lack of initiative characterize patients with dependent personality disorder. Obsessive-compulsive personality disorder involves inflexibility and excessive concern with details and rules, as well as an inability to spontaneously express emotions (sufferers of this disorder, however, do not experience uncontrollable compulsive thoughts and purposeless repetitive behaviors in the way those who suffer from the similarly named obsessive-compulsive disorder do). Passive-aggressive personality disorder, like antisocial personality disorder, involves non-compliance with social norms. However, the passive-aggressive patient does not openly defy laws or expectations, but rather resists influence indirectly by procrastination or intentional inefficiency. Disorders Associated with Childhood and Adolescence These disorders involve syndromes that tend to have their onset early in life. They cover a broad range of behavioral and cognitive disabilities and vary in severity and duration. Attention-deficit hyperactivity disorder (see \Lhyperactiv\le \TChildren\t) affects as many as 5 percent of all elementary school children and is more common in males than females. It is characterized by excessive movement or restlessness, and problems in maintaining attention. Pervasive developmental disorders are more serious and are characterized by extreme distortions in several functional domains, including language, perception, social and motor skills, and attention. \Tautism\t is one of the pervasive developmental disorders. Eating disorders, such as \Tanorexia nervosa\t and \Tbulimia\t also typically have their onset in childhood. HISTORY The modern scientific study of psychopathology has evolved out of a long-standing search for the causes of abnormal tendencies in human behavior. The earliest explanations for abnormal behavior were based on beliefs in the supernatural. Demonology, or the belief that an evil supernatural being can control a person's body or mind, was the rationale that most ancient cultures used for explaining psychopathology. These ideas are apparent in the cultural artifacts of the Babylonians, Egyptians, Chinese, and Greeks. In biblical times it was believed that the evil beings had to be exorcised from disturbed persons in order to make them well. \Texorcism\t took many forms, including praying for the afflicted, administering brews, or, in extreme cases, flogging and starving the victim. In the 5th century BC, \THippocrates\t and other Greek philosophers developed ideas about the origins of mental illness that are compatible in many ways with current theories in the field. The Hippocratic school recognized the brain as the seat of emotion and intellectual life and considered--as do contemporary researchers--the possibility that brain damage acquired early in life could contribute to subsequent psychopathology. Although many of the theories were insightful, Hippocratic biological theories were unsophisticated. They propounded, for instance, that imbalance of various bodily fluids determined individual temperament. From time to time, religious beliefs regained dominance in society's response to psychopathology. Medieval views of mental illness were heavily influenced by religion, and belief in witchcraft was common from the 10th through the 18th century. The practice of witchcraft, which involved dealings with the devil, was viewed as a denial of God and was punishable by torture and execution. Undoubtedly, many persons punished as witches were suffering from psychopathology. Medieval society, however, was also characterized by some more enlightened and sympathetic attitudes toward the mentally ill, and some modest advances in treatment. In 1243 the Priory of St. Mary of Bethlehem was established in London, and by 1403 its hospital routinely housed several mentally disturbed men. Eventually, it came to serve as the major institution for the mentally ill in London. A corruption of its name, bedlam, has passed into the language as a synonym for mad or chaotic conditions. Unfortunately, the hospital also became a source of amusement, and those with sufficient wealth purchased tickets to view the inmates. The number of asylums in Europe grew dramatically in the 15th and 16th centuries. As was the case with the Bethlehem hospital, however, the chief function of these institutions was behavioral control, and this often took the form of physical restraint. For example, at the "Lunatic's Tower" in Vienna, which was constructed in 1784, the inmates were not only confined to small cells, but were also restrained with chains, straps, and locks. Even so, humanitarian approaches to treatment were soon to gain a foothold in Europe. French physician Philippe Pinel (1745-1826) was one of the key figures in the quest for humane treatment for the mentally ill. He argued that they should be treated as sick individuals instead of as "wild animals." In 1793, after such resistance from authorities, Pinel was eventually given permission to remove the chains of the patients under his charge at Bicetre Hospital in Paris fostered the belief that through purposeful activity and being comforted, the "insane" could be restored to reason. His reforms rapidly spread throughout France. Another important figure in reform advocacy was American schoolteacher Dorothy \TDix\t. Her initial interest in psychopathology stemmed from her experience as a Sunday school teacher for female convicts, many of whom suffered from mental disorders. Dix subsequently gathered information on the maltreatment of people in U.S. mental institutions and advocated her cause with legislators until the situation was improved through legal statutes. She then traveled around the country inspecting psychiatric facilities to ensure that her reforms were put into practice. Ironically, although Dix forced monumental improvements, her promotion of the idea that all mentally ill people should have a comfortable place to recover led to an increase in the number of patients, and eventually, to an overcrowding problem in U.S. institutions. Enlightened attitudes toward the treatment of the mentally ill were accompanied by a more systematic, scientific study of mental disorders. In an 1883 textbook, German physicist Emil \TKraepelin\t advanced the first classification of the various mental disorders based on their presumed origins. He categorized groups of symptoms into syndromes, many of which he felt were attributable to organic dysfunctions. In Kraepelin's classification system each syndrome was presumed to be distinct from the others with respect to cause. Also in the 19th century, significant progress was made in research on the functioning of the nervous system. Some of the degenerative brain-cell changes accompanying senility and the structural pathologies associated with mental retardation were documented. Another discovery was the cause and consequences of the disease \Tsyphilis\t. By identifying the connection between syphilitic infection and the mental deterioration (general paresis) that accompanies it, the link between central-nervous-system impairment and mental-illness symptoms was clearly established. In the 20th century new discoveries in the field of \Tgenetics\t and neurobiology emerged, as did new theories of the causes of mental illness. Gradually accumulating data on the occurrence of mental illness in the biological relatives of patients led to theories that posited a hereditary component in such disorders as schizophrenia and major depression. As knowledge of the neurochemistry of the brain expanded, biochemical theories of mental disorders were proposed. Among these was the still prevalent theory that increased levels of the neurotransmitter dopamine (see \Tnervous system\t) in the brain may be a factor in schizophrenic disorders. Competing with the various biological approaches to mental illness were numerous theories of environmental causation. These are often referred to as psychogenic theories because they make the general assumption that conflict or emotional stress often contribute to mental illness. Some psychogenic theories, most notably Sigmund \TFreud\t's psychodynamic theory, propose that bad childhood experiences are the primary source of psychopathology. By assigning a role for environmental factors in the production of mental illness, psychogenic theories set the stage for the development of therapies (see \Tpsychoanalysis\t; \Tpsychotherapy\t) aimed at reducing dysfunction through psychological and environmental intervention. MODERN TREATMENT The introduction in the 1950's of a class of drugs known as the neuroleptics marked a watershed in the treatment of mental disorders. These drugs are effective in reducing the psychotic symptoms associated with schizophrenia and some affective disorders. Significant progress has also been made in the development of antidepressant medications, and \Tlithium\t has proven to be very effective in ameliorating the symptoms of bipolar disorder. As a result of the introduction of pharmacologic treatments, many patients who would have required hospitalization are now treated on an outpatient basis. This has contributed to a dramatic reduction in the number of hospitalized psychiatric patients. (See \Tpsychopharmacology\t.) A variety of psychotherapies are also currently used in the treatment of psychopathology. Approaches used include psychodynamic (concerned with cause and effect), cognitive (concerned with sensations and perceptions), and psychoeducational (concerned with educating sufferers about their disorders). Research has shown that psychotherapy is effective in treating major depression, especially when applied in conjunction with medication. For schizophrenics, the psychoeducational approach appears to be the most effective. Behavioral therapies, such as systematic desensitization and contingency management, are typically used to treat phobias, obsessive-compulsive disorders, eating disorders, and many childhood disorders. Psychotherapy and behavioral therapy are often components of inpatient treatment programs. In addition, hospitalization for psychopathology frequently includes drug therapy, as well as recreational and occupational therapies. More dramatic somatic therapies such as electroconvulsive \Tshock therapy\t, popular in the 1930's and 1940's, are used on a much more limited basis today. The chief goals of hospitalization are to reduce the patient's symptoms and to assist the patient in developing skills with which to function independently. Upon admission, an individualized treatment plan is developed and the staff monitors the patient's progress. When the patient shows sufficient improvement, a discharge plan is formulated to ease the patient's transition back into the community. There are a variety of programs for this purpose, including transitional living and outpatient facilities. Although the number and efficacy of available treatments have increased dramatically during this century, there is currently no "cure" for any of the psychopathologies. The neuroleptics, antidepressants, and lithium have all served to significantly improve the quality of life and prognosis for mental illness, yet none of these drugs completely restores the individual to mental health. Also, unfortunately, many very ill patients do not respond to medication. RECENT RESEARCH The results of research on the nature and determinants of mental illness indicate that causes are diverse and often complex. As early theorists, such as Kraepelin, would have predicted, there is now evidence that many forms of psychopathology are biologically based. For example, computerized axial tomography, or \LCAT scan\ls, of the brains of patients with schizophrenic and affective disorders have revealed that some of these patients have abnormalities of the brain. There is also substantial evidence of biochemical imbalance in the central nervous systems of some patients with panic disorders and depression. One potential source of such organic dysfunction is heredity. Research on genetics has revealed that vulnerability to psychopathology can be inherited. Up to this point, however, no specific genetic cause has been identified. Furthermore, genetic studies have demonstrated that heredity is not the sole determinant of mental illness. Monozygotic twins are genetically identical, yet it is often the case that one member of the twin pair will show a mental illness, such as schizophrenia or depression, while the other does not. This indicates that factors other than heredity are important contributors to psychopathology. Numerous environmental factors have been studied to determine their relationship to mental illness. For instance, researchers recently have found evidence that obstetric complications and viral infections may have an adverse effect on the central nervous system of the newborn and lead to psychopathology. The role of other environmental factors, such as emotional conflict, in mental illness also continues to be the focus of such research. ELAINE K. \TWalker\t Bibliography: Ailborg, G., and Henry, G. W., A History of Medical Psychology (1941); American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders, 3rd rev. ed. (1987); Bockhoven, J., Moral Treatment in American Psychiatry (1963); Colman, J. C., and Butcher, J. N., Abnormal Psychology and Modern Life, 7th ed. (1984); Davis, D. R., An Introduction to Psychopathology, 4th ed. (1986); Davison, G. C., and Neale, J. M., Abnormal Psychology, 4th ed. (1986); Farina, A., Abnormal Psychology (1976); Goldstein, M. J., et al., Abnormal Psychology, 2nd ed. (1986); Nathan, P. E., and Harris, S. L., Psychopathology and Society, 2nd ed. (1980).