Psychology
The Short Version

Neurosis

in psychiatry, a broad category of psychological disturbance, encompassing various mild forms of mental disorder. Until fairly recently, the term neurosis was broadly employed in contrast with psychosis, which denoted much more severe, debilitating mental disturbances. The two terms were used regularly until 1980, when the American Psychiatric Association released a precise listing of known mental disorders excluding the two broad categories of “mild” and “serious” mental disorders. Neurosis, according to Sigmund Freud , arose from inner conflicts and could lead to anxiety . In his formulation, the causal factors could be found roughly in the first six years of life, when the personality, or ego, is weak and afraid of censure. He attributed neurosis to the frustration of infantile sexual drives, as when severe eating and toilet habits and other restrictions are parentally imposed (see Oedipus complex ), which appear in adulthood as neurotic symptoms (see psychoanalysis ). Other authorities have emphasized constitutional and organic factors. Among the psychoanalysts, Alfred Adler and H. S. Sullivan stressed social determinants of personal adjustment, and Karen Horney emphasized insecurity in childhood as causes of neurosis.

Until 1980, neuroses included anxiety disorders as well as a number of other mild mental illnesses, such as hysteria and hypochondria . Anxiety disorders are fairly common, and generally involve a feeling of apprehension with no obvious, immediate cause. Such intense fears of various situations may be severe enough to prevent individuals from conducting routine activities. Phobias, the most common type of anxiety disorder, involve specific situations which cause irrational anxiety attacks. For instance, an individual with agoraphobia (fear of open spaces) may be too anxious to leave their house. Obsessive-compulsive disorder occurs when an individual relentlessly pursues a thought or action in order to relieve anxiety. Panic disorder is characterized by anxiety in the form of panic attacks, while generalized anxiety disorder occurs when an individual experiences chronic anxiety with no apparent explanations for the anxiety. Post-traumatic stress disorder , occurring in the wake of a particularly traumatic event, can lead to severe flashbacks and a lack of responsiveness to stimuli. Anxiety disorders are usually accompanied by a variety of defense mechanisms , which are employed in an attempt to overcome anxiety. Hypochondriasis and hysteria (now generally known as conversion disorder) are classified today as somatoform disorders, and involve physical symptoms of psychological distress. The hypochondriac fears that minor bodily disturbances indicate serious, often terminal, disease, while the individual suffering from conversion disorder experiences a bodily disturbance such as paralysis of a limb, blindness, or deafness with no clear biological origin. Treatment of neurosis may include behavior therapy to condition an individual to change neurotic habits, psychotherapy, and group psychotherapy . Various drugs may also be employed to alleviate symptoms.

Oedipus complex

Freudian term, drawn from the myth of Oedipus , designating attraction on the part of the child toward the parent of the opposite sex and rivalry and hostility toward the parent of its own. It occurs during the phallic stage of the psycho-sexual development of the personality, approximately years three to five. Resolution of the Oedipus complex is believed to occur by identification with the parent of the same sex and by the renunciation of sexual interest in the parent of the opposite sex. Freud considered this complex the cornerstone of the superego and the nucleus of all human relationships. Many psychiatrists, while acknowledging the significance of the Oedipal relationships to personality development in our culture, ascribe love and attraction toward one parent and hatred and antagonism toward the other not necessarily to sexual rivalry but to resentment of parental authoritarian power.

Oedipus Folklore

(ed´ipes, e´di-) , in Greek legend, son of Laius, king of Thebes, and his wife, Jocasta. Laius had been warned by an oracle that he was fated to be killed by his own son; he therefore abandoned Oedipus on a mountainside. The baby was rescued, however, by a shepherd and brought to the king of Corinth, who adopted him. When Oedipus was grown, he learned from the Delphic oracle that he would kill his father and marry his mother. He fled Corinth to escape this fate, believing his foster parents to be his real parents. At a crossroad he encountered Laius, quarreled with him, and killed him. He continued on to Thebes, where the sphinx was killing all who could not solve her riddle. Oedipus answered it correctly and so won the widowed queen's hand. The prophecy was thus fulfilled. Two sons, Polynices and Eteocles, and two daughters, Antigone and Ismene, were born to the unwittingly incestuous pair. When a plague descended on Thebes, an oracle declared that the only way to rid the land of its pollution was to expel the murderer of Laius. Through a series of painful revelations, brilliantly dramatized by Sophocles in Oedipus Rex, the king learned the truth and in an agony of horror blinded himself. According to Homer, Oedipus continued to reign over Thebes until he was killed in battle; but the more common version is that he was exiled by Creon, Jocasta's brother, and his sons battled for the throne (see Seven against Thebes ). In Sophocles' Oedipus at Colonus, Oedipus is guided in his later wanderings by his faithful daughter, Antigone.

Anxiety

anticipatory tension or vague dread persisting in the absence of a specific threat. In contrast to fear, which is a realistic reaction to actual danger, anxiety is generally related to an unconscious threat. Physiological symptoms of anxiety include increases in pulse rate and blood pressure, accelerated breathing rates, perspiration, muscular tension, dryness of the mouth, and diarrhea. Freud postulated that anxiety was a result of repressed, pent-up sexual energy, but later came to view it as a danger signal alerting the ego to excessive stimulation and causing repression. Anxiety disorders include observable, overt anxiety, as well as phobias and other conditions where a defense mechanism has been set up to disguise the anxiety from both the sufferer and the observer. In generalized anxiety, the individual experiences long-term anxiety with no explanation for its cause; such a condition may be called free-floating, since it is not linked to a specific stimulus. Panic disorder involves sudden anxiety attacks which are manifested in heart palpitations, shortness of breath, or fainting. The individual with a phobic disorder can identify the stimulus that causes anxiety: such stimuli as enclosed space, heights, and crowds become imbued with greatly exaggerated anxiety and are carefully avoided by the phobic individual. Obsessive-compulsive disorders (OCD) are characterized by obsessions (mental quandaries) and compulsions (physical actions) that engage the individual excessively. Extreme anxiety may be experienced if the person does not carry out the compulsion or attempts to ignore the obsession. Post-traumatic stress disorder occurs when an individual has recurrent dreams, flashbacks, or panic attacks after a particularly traumatic experience.

Defense Mechanism

in psychoanalysis, any of a variety of unconscious personality reactions which the ego uses to protect the conscious mind from threatening feelings and perceptions. Sigmund Freud first used defense as a psychoanalytic term (1894), but he did not break the notion into categories, viewing it as a singular phenomenon of repression. His daughter, Anna Freud , expanded on his theories in the 1930s, distinguishing some of the major defense mechanisms recognized today. Primary defense mechanisms include repression and denial , which serve to prevent unacceptable ideas or impulses from entering the conscience. Secondary defense mechanisms generally appearing as an outgrowth of the primary defense mechanisms include projection, reaction formation, displacement, sublimation, and isolation.

Denial

in psychology, an ego defense mechanism that operates unconsciously to resolve emotional conflict, and to allay anxiety by refusing to perceive the more unpleasant aspects of external reality. In the psychoanalytic theory of Sigmund Freud , denial is described as a primitive defense mechanism . Anna Freud studied the widespread occurrence of denial among small children and explained that the mature ego does not continue to make extensive use of denial, because it conflicts with the capacity to recognize and critically test reality. Most people employ denial at some time in their lives when coping with stressful situations, such as the death of a loved one. Elisabeth Kübler-Ross 's influential theory describes denial as the first stage of a dying person's progress in coming to terms with terminal illness. In such instances, denial may be considered adaptive. It is considered maladaptive, however, when it becomes delusional. In recent years, the term is used more generally, to describe the suppression of reality rather than a particular defense mechanism in the Freudian sense.

Post-Traumatic Stress Disorder

(PTSD), mental disorder that follows an occurrence of extreme psychological stress, such as that encountered in war or resulting from violence, childhood abuse, sexual abuse, or serious accident. The stressful event is usually followed by a period of emotional numbness and denial that can last for months or years. After that period, symptoms such as recurring nightmares, “flashbacks,” short-term memory problems, insomnia, or heightened sensitivity to sudden noises may begin. In some cases outbursts of violent behavior have been observed. The usual treatment for PTSD is individual psychotherapy, including anxiety management, or group psychotherapy with others who have the disorder. Some anti-anxiety and antidepressant drugs are being studied for their effectiveness. Certain traits (a history of depression, shyness, impulsivity) appear to heighten a person's risk of experiencing PTSD after a traumatic event. In those who do experience it, there is growing evidence that actual physical changes occur in the brain. The hippocampus, a structure that lies deep in the brain and that is associated with memory, has been found to be smaller in PTSD victims. It has been hypothesized that excesses of cortisol, a steroid hormone released during periods of extreme stress, may damage nerve fibers in the area or actually kill the nerve cells. However, the role of cortisol is not completely understood; studies of concentration camp survivors found abnormally low levels of cortisol rather than abnormally high levels.

Post-traumatic stress disorder was referred to as “shell shock” after World War I and as “battle fatigue” after World War II and was traditionally thought of as a condition of war veterans. Studies of Vietnam veterans and Nazi concentration camp survivors have added greatly to the knowledge of PTSD. The National Vietnam Veterans Readjustment Study (1988) estimated that 31% of the males and 27% of the females who served in the Vietnam War had symptoms of PTSD. Estimates of civilian populations put the rate of PTSD at 10% (women) and 5% (men) in the 15 to 54 age group. Childhood sexual abuse, sexual abuse, and assault are common causes of PTSD in both military and nonmilitary women. In 1989 the U.S. Congress created the National Center for Post-Traumatic Stress Disorder for the study and treatment of PTSD.

Hysteria

(hister´ee) , in psychology, a disorder commonly known today as conversion disorder, in which a psychological conflict is converted into a bodily disturbance. It is distinguished from hypochondria by the fact that its sufferers do not generally confuse their condition with real, physical disease. Conversion disorder is usually found in patients with immature, histrionic personalities who are under great stress. Women are affected twice as frequently as men. Symptoms, which are largely symbolic and which relieve the patient's anxiety, include limb paralysis, blindness, or convulsive seizures. The specific physical disorder usually does not correspond to the anatomy; e.g., an entire limb may be paralyzed rather than a specific group of muscles. The person may also appear to be unconcerned about the illness, a condition French psychiatrist Pierre Janet called la belle indifference (1929). At the end of the 19th cent., great advances were made in the understanding and cure of hysteria by the recognition of its psychogenic nature and by the use of hypnotism to influence the hysteric patient, who is known to have a high degree of suggestibility. The Austrian physician Josef Breuer , the French psychologists J. M. Charcot and Pierre Janet, and Austrian psychiatrist Sigmund Freud were pioneers in the investigation of hysteria through hypnosis. Freud concluded that hysterical symptoms were symbolic representations of a repressed unconscious event, accompanied by strong emotions that could not be adequately expressed or discharged at the time. Instead, the strong effect associated with the event was diverted into the wrong somatic channels (conversion), and the physical symptom resulted. Psychoanalysis has had reasonable success in helping patients suffering from conversion disorder.

Hypochondria

(hipekon´dree) , in psychology, a disorder characterized by an exaggeration of imagined or negligible physical ailment. The hypochondriac fears that such minor symptoms indicate a serious disease, and tends to be self-centered and socially withdrawn. Continually seeking professional help to reinforce his fears, the hypochondriac never feels he is receiving adequate care. Contemporary theorists have arrived at similar conclusions, suggesting that the physical ailments of hypochondriacs were a form of escape from psychological stress. The disorder is technically known as hypochondriasis, and is classified as a somatoform disorder, or one in which a psychological problem manifests itself in a physical ailment.

Psychoanalysis

name given by Sigmund Freud to a system of interpretation and therapeutic treatment of psychological disorders. Psychoanalysis began after Freud studied (1885-86) with the French neurologist J. M. Charcot in Paris and became convinced that hysteria was caused not by organic symptoms in the nervous system but by emotional disturbance. Later, in collaboration with Viennese physician Josef Breuer , Freud wrote two papers on hysteria (1893, 1895) that were the precursors of his vast body of psychoanalytic theory. Freud used his psychoanalytic method primarily to treat clients suffering from a variety of mild mental disorders classified until recently as neuroses (see neurosis ). Freud was joined by an increasing number of students and physicians, among whom were C. G. Jung and Alfred Adler . Both made significant contributions, but by 1913 ceased to be identified with the main body of psychoanalysts because of theoretical disagreements with Freud's strong emphasis on sexual motivation. Other analysts, including Melanie Klein and Jacques Lacan , also have contributed greatly to the field. Psychoanalysis and its theoretical underpinnings have had an enormous influence on modern psychology and psychiatry and in fields as diverse as literary theory, anthropology, and film criticism.

Unconscious

in psychology, that aspect of mental life that is separate from immediate consciousness and is not subject to recall at will. Sigmund Freud regarded the unconscious as a submerged but vast portion of the mind. In his view, the unconscious was composed of the id, which accounts for instinctual drives, acts as the motivating force in human behavior, and contains desires and wishes that the individual hides or represses from conscious recognition; and part of the superego, the system that acts to restrain and control id impulses. Conscious cognitive processes, such as thinking, are performed by the ego and part of the superego (see psychoanalysis ). Conflict between conscious and unconscious impulses are said to give rise to anxiety , then to defense mechanisms , which counteract this anxiety. To tap the unconscious, Freud used a variety of techniques, including hypnosis, free association, and dream interpretation. C. G. Jung expanded on the Freudian concept, adding the idea of an inherited unconscious, known as the collective unconscious. The idea of the unconscious has been rejected by some psychological schools, although it is still used by many psychoanalysts. The term unconscious is also used to describe latent, or unretrieved, memories, or to describe stimuli too weak to enter an individual's conscious awareness.

Consciousness

in psychology, a term commonly used to indicate a state of awareness of self and environment. In Freudian psychology, conscious behavior largely includes cognitive processes of the ego, such as thinking, perception, and planning, as well as some aspects of the superego, such as moral conscience. Some psychologists deny the distinction between conscious and unconscious behavior; others use the term consciousness to indicate all the activities of an individual that constitute the personality. In recent years, neuropsychologists have begun to investigate the links between consciousness and memory, as well as altered states of consciousness such as the dream state. See also defense mechanism ; psychoanalysis .

Association

in psychology, a connection between different sensations, feelings, or ideas by virtue of their previous occurrence together in experience. The concept of association entered contemporary psychology through the empiricist philosophers John Locke, George Berkeley, David Hume, and David Hartley , and the British associationist school of James Mill , John Stuart Mill , and others (see associationism ). Translated into the stimulus-response terms of behaviorism , association has been thought of as the basis of learning and conditioning. Paired experience and the principle of reinforcement are often invoked to explain associative learning. However, Gestalt psychologists, who believe that association between items is dependent on their relations to each other, interpret association as an aftereffect of perceptual organization. Psychoanalysis uses a technique known as free association, in which the client expresses thoughts exactly as they occur, even though they may seem irrelevant. This procedure is designed to reveal areas of conflict and to bring into consciousness traumatic events that have been repressed, the theory being that earlier thoughts and associations can be derived from current thoughts with similar patterns of association.

Associationism

theory that all consciousness is the result of the combination, in accordance with the law of association , of certain simple and ultimate elements derived from sense experiences. It was developed by David Hartley and advanced by James Mill .

Behaviorism

school of psychology which seeks to explain animal and human behavior entirely in terms of observable and measurable responses to environmental stimuli. Behaviorism was introduced (1913) by the American psychologist John B. Watson , who insisted that behavior is a physiological reaction to environmental stimuli. He rejected the exploration of mental processes as unscientific. The conditioned-reflex experiments of the Russian physiologist Ivan Pavlov and the American psychologist Edward Thorndike were central to the development of behaviorism. The American behaviorist B. F. Skinner contended that all but a few emotions were conditioned by habit, and could be learned or unlearned. The therapeutic system of behavior modification has emerged from behaviorist theory. Therapy intends to shape behavior through a variety of processes known as conditioning. Popular techniques include systematic desensitization, generally used on clients suffering from anxiety or fear of an object or situation, and aversive conditioning, employed in cases where a client wishes to be broken of an unhealthy habit (such as smoking or drug abuse). Other behavior therapies include systems of rewards or punishments, and modeling, in which the client views situations in which healthy behaviors are shown to lead to rewards.

Behavior Therapy

or behavior modification, in psychology, treatment of human behavioral disorders through the reinforcement of acceptable behavior and suppression of undesirable behavior. The technique had its roots in the work of Ivan Pavlov , a Russian physiologist who observed that animals could be taught to respond to stimuli that might otherwise have no effect on them. B. F. Skinner developed the technique in the United States, using positive or negative reinforcers to encourage desirable behavior and punishments to discourage undesirable behavior. Behavior therapists believe that, in many cases, behaviors can be learned or unlearned through basic conditioning techniques; unlike traditional psychoanalysis, the method has little regard for the unconscious processes underlying personality disorders. Behavior therapy uses such techniques as aversive conditioning, where unwanted habits are paired with unpleasant stimuli, and systematic desensitization, where a stimulus that causes anxiety is paired with a pleasant one.

Gestalt

(geshtält´) [Ger.,form], school of psychology that interprets phenomena as organized wholes rather than as aggregates of distinct parts, maintaining that the whole is greater than the sum of its parts. The term Gestalt was coined by the philosopher Christian von Ehrenfels in 1890, to denote experiences that require more than the basic sensory capacities to comprehend. In 1912, the movement was given impetus in psychology by German theorists Max Wertheimer , Wolfgang Köhler , and Kurt Koffka as a protest against the prevailing atomistic, analytical psychological thought. It was also a departure from the general intellectual climate, which emphasized a scientific approach characterized by a detachment from basic human concerns. According to the school, understanding of psychological phenomena such as perceptual illusions could not be derived by merely isolating the elementary parts for analysis, because human perception may organize sensory stimuli in any number of ways, making the whole different from the sum of the parts. Gestalt psychologists suggest that the events in the brain bear a structural correspondence to psychological events; indeed, it has been shown that steady electric currents in the brain correspond to structured perceptual events. The Gestalt school has made substantial contributions to the study of learning, recall, and the nature of associations, as well as important contributions to personality and social psychology. Gestalt therapy, developed after World War II by Frederick Perls, believes that a person's inability to successfully integrate the parts of his personality into a healthy whole may lie at the root of psychological disturbance. In therapy, the analyst encourages clients to release their emotions, and to recognize these emotions for what they are. Gestalt psychology has been thought of as analogous to field physics.

Dream

mental activity associated with the rapid-eye-movement (REM) period of sleep. It is commonly made up of a number of visual images, scenes or thoughts expressed in terms of seeing rather than in those of the other senses or in words. Electroencephalograph studies, measuring the electrical activity of the brain during REM sleep, have shown that young adults dream for 1 12 to 2 hours of every 8-hour period of sleep. Infants spend an average of 50% of their sleep in the REM phase (they are believed to dream more often than adults) a figure which decreases steadily with age. During dreams, blood pressure and heart rate increase, and breathing is quickened, but the body is otherwise immobile. Studies have shown that sleepers deprived of dream-sleep are likely to become irritable and lose coordination skills. Unusually frightening dreams are called nightmares, and daydreams are constructed fantasies that occur while the individual is awake. Studies have demonstrated the existence of lucid dreaming, where the individual is aware that he is dreaming and has a degree of control over his dream. Sigmund Freud , in his pioneering work The Interpretation of Dreams (1900, tr. 1913), was one of the first to emphasize dreams as keys to the unconscious. He distinguished the manifest content of dreams the dream as it is recalled by the individual from the latent content or the meaning of the dream, which Freud saw in terms of wish fulfillment. C. G. Jung held that dreams function to reveal the unconscious mind, anticipate future events, and give expression to neglected areas of the dreamer's personality. Another theory, which PET scan studies appear to support, suggests that dreams are a result of electrical energy that stimulates memories located in various regions of the brain.

Psychotherapy

treatment of mental and emotional disorders using psychological methods. Psychotherapy, thus, does not include physiological interventions, such as drug therapy or electroconvulsive therapy , although it may be used in combination with such methods. This type of treatment has been used in one form or another through the ages in many societies, but it was not until the late 19th cent. that it received scientific impetus, primarily under the leadership of Sigmund Freud . Although Freud's theoretical formulations have come sharply into question, his treatment method involving individualized client-psychologist sessions has been used in modified forms for years (see psychoanalysis ). Behavior therapy aims to help the patient eliminate undesirable habits or irrational fears through conditioning. Techniques include systematic desensitization, particularly for the treatment of clients with irrational anxieties or fears, and aversive conditioning, which uses negative stimuli to end bad habits. Humanistic therapy tends to be more optimistic, basing its treatment on the theory that individuals have a natural inclination to strive toward self-fulfillment. Therapists such as Carl Rogers and Abraham Maslow used a highly interactive client-therapist relationship, compelling clients to realize exactly what they are saying or how they are behaving, in order to foster a sense of self-awareness. Cognitive therapies try to show the client that certain, usually negative, thoughts are irrational, with the goal of restructuring such thoughts into positive, constructive ideas. Such methods include Albert Ellis's rational-emotive therapy, where the therapist argues with the client about his negative ideas; and Aaron Beck's cognitive restructuring therapy, in which the therapist works with the client to set attainable goals. Other forms of therapy stress helping patients to examine their own ideas about themselves.

Psychotherapy may be brief, lasting just a few sessions, or it may extend over many years. More than one client may be involved, as in marriage or family counseling, or a number of individuals, as in group psychotherapy .

Group Psychotherapy

a means of changing behavior and emotional patterns, based on the premise that much of human behavior and feeling involves the individual's adaptation and response to other people. It is a process carried out in formally organized groups of three or more individuals who seek change, whether their problem is alcoholism, overeating, or poor social skills. The composition of a group may be heterogenous or homogeneous with reference to the age of the members or the type of problem. The therapist may be directive or nondirective, allowing the group to set their own agenda for discussion. The group becomes a “sample” of the outside world, reproducing conditions of interpersonal relationships; its members jointly participate in observing personal motivation and styles of interaction. They also participate in attempting new behaviors and dealing with the consequences of such behaviors, with the intended result that they will eventually be able to employ these behavior patterns outside the group. In observing the totality of the events that take place in group therapy, the process by which elements of personality are developed in each member is also studied.

Group Psychotherapy
Section: Origins of Group Therapy

The technique of formally organized group therapy is said to have been devised by J. H. Pratt in 1905. Pratt was holding general-care instruction classes for recently discharged tuberculosis patients when he noticed the impact of this experience on their emotional states. In 1925 psychoanalyst Trigant Burrow became dissatisfied with individual psychoanalysis, and began experimenting with group techniques. Burrow hoped to decrease the authoritarian position of the therapist, and to more thoroughly examine interpersonal interactions. The application of group therapy methods to prison inmates and discharged mental hospital patients was pioneered by Paul Schilder and Louis Wender in the 1930s. At that time group therapy was found to be particularly useful in the treatment of children and adolescents. The development of group therapy was given impetus during World War II, as a result of the large number of soldiers requiring treatment.

Group Psychotherapy
Section: Types of Group Therapy

There are various types of group therapy; approaches include behavior therapy, psychoanalytic therapy, sensitivity training, or Gestalt psychology (see psychotherapy ). The composition of groups varies as well, with family therapy and marriage counseling common forms in recent years. Peer group therapy usually consists of a group of individuals who have similar problems, and can be mediated by a psychoanalyst or by the members themselves. Many people seeking help prefer this sort of group therapy over individual therapy, largely because of the comfort derived from knowing that others share their problems. The approach is nondirective, and in some cases, the individual can continue attending sessions whenever they are needed. Alcoholics Anonymous (AA) is a well-known peer support group, run entirely by members. AA has been influential in the formation of similar groups, particularly support groups centered on addictions.

Cognitive Psychology

school of psychology that examines internal mental processes such as problem solving, memory, and language. It had its foundations in the Gestalt psychology of Max Wertheimer , Wolfgang Köhler , and Kurt Koffka , and in the work of Jean Piaget , who studied intellectual development in children. Cognitive psychologists are interested in how people understand, diagnose, and solve problems, concerning themselves with the mental processes which mediate between stimulus and response. Cognitive theory contends that solutions to problems take the form of algorithms rules that are not necessarily understood but promise a solution, or heuristics rules that are understood but that do not always guarantee solutions. In other instances, solutions may be found through insight, a sudden awareness of relationships. Cognitive psychologists have tried to reach a greater understanding of human memory (see memory ) and language. In recent years, cognitive psychology has become associated with information processing, which examines artificial intelligence in computers to find out whether they are capable of problem solving in ways similar to humans. Information processing theory studies the parallels between the human brain and the computer, in the ways that both can receive, process, store, and retrieve information.

Memory

in psychology, the storing of learned information, and the ability to recall that which has been stored. It has been hypothesized that three processes occur in remembering: perception and registering of a stimulus; temporary maintenance of the perception, or short-term memory; and lasting storage of the perception, or long-term memory. Two major recognized types of long-term memory are procedural memory, involving the recall of learned skills, and declarative memory, the remembrance of specific stimuli. For long-term memory to occur, there must be a period of information consolidation. The process of forgetting was first studied scientifically by Hermann Ebbinghaus, a German experimental psychologist, who performed memory tests with groups of nonsense syllables (disconnected syllables without associative connection). Ebbinghaus showed that the rate of forgetting is greatest at first, gradually diminishing until a relatively constant level of retained information is reached. Theories to explain forgetting include the concept of disuse, which proposes that forgetting occurs because stored information is not used, and that of interference, which suggests that old information interferes with information learned later and new information interferes with previously learned information.

In some instances, memory loss is an organic, physiological process. Retrograde amnesia , i.e., the failure to remember events preceding a head injury, is evidence of interrupted consolidation of memory. In anterograde amnesia, events occurring after brain damage e.g., in head injury or alcoholism may be forgotten. Memory loss may also result from brain cell deterioration following a series of strokes, cardiovascular disease, or Alzheimer's disease (see dementia ).

Physiologically, learning involves modification of neural pathways. PET scans and related studies have shown certain parts of the brain, such as the frontal lobe of the cerebral cortex and a structure called the hippocampus, to be particularly active in recall. Computer models of brain memory are called neural networks . In a study using genetic manipulation, a mouse with enhanced memory capabilities has been produced.

Manic-Depressive Disorder

or bipolar disorder, severe mental disorder involving manic episodes that are usually accompanied by episodes of depression . The term was introduced by the German psychiatrist Emil Kraepelin in 1896. The manic phase of the disorder is characterized by an abnormally elevated or irritable mood, grandiosity, sleeplessness, extravagance, and a tendency toward irrational judgment. During the depressed phase, the person tends to appear lethargic and withdrawn, shows a lack of concentration, and expresses feelings of worthlessness, self-blame, and guilt. The dual character of manic-depressive disorder has given it the name bipolar disorder, in contrast to the unipolar depression symptomatic of the majority of mood disorders. The symptoms range in intensity and pattern and may not be recognized at first. Individuals suffering from bipolar disorder may have long periods in their lives without episodes of mania or depression, but manic-depressives have the highest suicide rate of any group with a psychological disorder.

Depression

in psychiatry, a symptom of mood disorder characterized by intense feelings of loss, sadness, hopelessness, failure, and rejection. The two major types of mood disorder are unipolar disorder, also called major depression, and bipolar disorder, whose sufferers are termed manic-depressive (see manic-depressive disorder ). Close to 20% of Americans are likely to suffer major depression at some time, and women tend to be more susceptible to the disorder than men. Major depression is likely to interfere significantly with everyday activity, with symptoms including insomnia, irritability, weight loss, and a lack of interest in outside events. The disorder may last several months or longer and may recur but it is generally reversible in the short run. Bipolar disorder is much rarer, affecting only about 1% of the U.S. population; women and men tend to be equally susceptible. Its sufferers alternate between states of depression similar to that which is experienced in unipolar disorder and mania, which is characterized by intense euphoria and frenetic activity. Bipolar disorders are often interspersed with periods of relatively normal behavior, which may last for long periods of time between episodes of depression or mania. Manic-depressives have an extremely high rate of suicide, and episodes of the disorder tend to recur. Other types of depression are recognized, with characteristics similar to the major mood disorders, but not as severe: they are adjustment disorder with depression, dysthymic disorder, and cyclothymic disorder. Medical evidence suggests that depressive states may be connected to deficiencies in the neurotransmitters norepinephrine and serotonin , and there has been success with electroconvulsive therapy (ECT) for major depression, and drug therapy particularly lithium for manic-depression. In recent years, theorists have argued that many depressed individuals depend upon others for their self-esteem, and that the loss of one of these emotional supports often precipitates a depressive reaction. A number of psychologists contend instead that depression is a result of learned helplessness, which occurs when a person determines through experience that his actions are useless in making positive changes. Other theorists have shown that genetic factors play a major role in depression.

Manic-Depressive Disorder
Section: Incidence

Estimates suggest that about 2 million Americans suffer from bipolar disorders. Symptoms usually appear in adolescence or early adulthood and continue throughout life. The disorder occurs in males and females equally and is found more frequently in close relatives of people already known to have it.. It has had notable incidence among creative individuals, affecting such artists as Hector Berlioz, Gustav Mahler, Ernest Hemingway, and Virginia Woolf.

Manic-Depressive Disorder
Section: Treatment

Therapy includes lithium (to control mania and stabilize mood swings), anticonvulsant drugs such as valproate and carbamazepine, and antidepressants . Electroconvulsive therapy has been useful in cases where other treatments have had little success. Psychotherapy can provide support to the patient and the family.

Learning

in psychology, the process by which a relatively lasting change in potential behavior occurs as a result of practice or experience. Learning is distinguished from behavioral changes arising from such processes as maturation and illness, but does apply to motor skills, such as driving a car, to intellectual skills, such as reading, and to attitudes and values, such as prejudice. There is evidence that neurotic symptoms and patterns of mental illness are also learned behavior. Learning occurs throughout life in animals, and learned behavior accounts for a large proportion of all behavior in the higher animals, especially in humans.

Learning Section: Models of Learning

The scientific investigation of the learning process was begun at the end of the 19th cent. by Ivan Pavlov in Russia and Edward Thorndike in the United States. Three models are currently widely used to explain changes in learned behavior; two emphasize the establishment of relations between stimuli and responses, and the third emphasizes the establishment of cognitive structures. Albert Bandura maintained (1977) that learning occurs through observation of others, or models; it has been suggested that this type of learning occurs when children are exposed to violence in the media.

Classical Conditioning

The first model, classical conditioning, was initially identified by Pavlov in the salivation reflex of dogs. Salivation is an innate reflex, or unconditioned response, to the presentation of food, an unconditioned stimulus. Pavlov showed that dogs could be conditioned to salivate merely to the sound of a buzzer (a conditioned stimulus), after it was sounded a number of times in conjunction with the presentation of food. Learning is said to occur because salivation has been conditioned to a new stimulus that did not elicit it initially. The pairing of food with the buzzer acts to reinforce the buzzer as the prominent stimulus.

Operant Conditioning

A second type of learning, known as operant conditioning, was developed around the same time as Pavlov's theory by Thorndike, and later expanded upon by B. F. Skinner . Here, learning takes place as the individual acts upon the environment. Whereas classical conditioning involves innate reflexes, operant conditioning requires voluntary behavior. Thorndike showed that an intermittent reward is essential to reinforce learning, while discontinuing the use of reinforcement tends to extinguish the learned behavior. The famous Skinner box demonstrated operant conditioning by placing a rat in a box in which the pressing of a small bar produces food. Skinner showed that the rat eventually learns to press the bar regularly to obtain food. Besides reinforcement, punishment produces avoidance behavior, which appears to weaken learning but not curtail it. In both types of conditioning, stimulus generalization occurs; i.e., the conditioned response may be elicited by stimuli similar to the original conditioned stimulus but not used in the original training. Stimulus generalization has enormous practical importance, because it allows for the application of learned behaviors across different contexts. Behavior modification is a type of treatment resulting from these stimulus/response models of learning. It operates under the assumption that if behavior can be learned, it can also be unlearned (see behavior therapy ).

Cognitive Learning

A third approach to learning is known as cognitive learning. Wolfgang Köhler showed that a protracted process of trial-and-error may be replaced by a sudden understanding that grasps the interrelationships of a problem. This process, called insight, is more akin to piecing together a puzzle than responding to a stimulus. Edward Tolman (1930) found that unrewarded rats learned the layout of a maze, yet this was not apparent until they were later rewarded with food. Tolman called this latent learning, and it has been suggested that the rats developed cognitive maps of the maze that they were able to apply immediately when a reward was offered.

Multiple Personality

a very rare psychological disorder in which a person has two or more distinct personalities, each with its own thoughts, feelings, and patterns of behavior. The personalities often are direct opposites and dominate at different times, with abrupt transitions triggered by distressful events or memories. Each may be entirely unaware of the other but aware of unexplained gaps in remembered time. In psychiatry the condition is known as dissociative identity disorder. The term “split personality,” denoting schizophrenia , refers to an unrelated disorder in which the split (separation) is between thought and feeling. Multiple personality was first recognized and described by the French physician Pierre Janet in the late 19th cent. Public awareness of the disorder increased in contemporary times after a case was the subject of The Three Faces of Eve (1957). In the 1980s and early 90s, such factors as recognition of child abuse, public interest in memories recovered from childhood (whether of actual or imagined events), allegations of so-called satanic ritual abuse, and the willingness of many psychotherapists to assume a more directive role in their patients' treatment, led to what came to be regarded as a rash of over diagnoses of multiple personality.

The cause of multiple personality is not clearly understood, but the condition seems almost invariably to be associated with severe physical abuse and neglect in childhood. It is believed that amnesia , the key to formation of the separate personalities, occurs as a psychological barrier to seal off unbearably painful experiences from consciousness. The disorder often occurs in childhood but may not be recognized until much later. Social and psychological impairment ranges from mild to severe. The primary treatment is psychotherapy to help the individual integrate the separate personalities.

Schizophrenia

(skitsefre´nee) , group of severe mental disorders characterized by reality distortions resulting in unusual thought patterns and behaviors. Because there is often little or no logical relationship between the thoughts and feelings of a person with schizophrenia, the disorder has often been called “split personality.” However, the condition should not be confused with multiple personality , a disorder in which the individual has two or more distinct personalities that dominate at different times. In 1896, the German psychiatrist Emil Kraepelin grouped what were previously considered unrelated mental diseases under the term dementia praecox. It was not until 1908, however, that an influential essay by Swiss psychiatrist Eugen Bleuler corrected Kraepelin's theory that the disease was an organic brain deterioration and thus incurable. Bleuler introduced the term schizophrenia to replace dementia praecox, emphasizing the dissociative phenomena in the mind and avoiding the implications of early onset and progressive brain deterioration.

Schizophrenic disorders generally begin in the late teenage years or early adulthood and tend to occur in withdrawn, seclusive individuals. The lifetime prevalence worldwide has been estimated to be just under 1%, and the disorder affects 1.5 to 2 million people in the United States alone. Symptoms include disturbances of thought, both in form and content (see delusion ), and disturbances of perception, most commonly appearing as visual or aural hallucinations .

There are five major types of schizophrenia listed by the American Psychiatric Association in its Diagnostic and Statistical Manual of Mental Disorders. The most severe are disorganized (hebephrenic) schizophrenia, characterized by hallucinations, delusions, inappropriate laughing and crying, incoherent speech, and infantile behavior; and catatonic schizophrenia, characterized by physical rigidity or hyperactivity. Paranoid schizophrenics can often function relatively normally, although they may be disturbed by persecutory delusions and hallucinations, and they tend to exhibit argumentative behavior. The presence of a combination of symptoms from other types is classified as undifferentiated schizophrenia. Residual schizophrenia is constituted by minor symptoms, which occur as an active episode diminishes.

The cause of schizophrenia is unknown. Genetic factors appear to be involved in producing susceptibility to the condition, with studies among identical twins showing a 50% concordance rate, a figure that has been confirmed by the results of adoption studies. Biochemical research suggests that high levels of the neurotransmitter dopamine, or excessive numbers of receptors for dopamine, may be at the root of schizophrenia. Medical imaging studies have revealed various physical and physiological anomalies in some patients. Other research has focused on mistiming of neural responses to stimuli in the brain. Many researchers maintain that a combination of influences, including such environmental factors as viral illness or malnutrition in the patient's mother during pregnancy, may lead to schizophrenia,

Antipsychotic drugs (see psychopharmacology ), sometimes in conjunction with psychotherapy, have greatly improved the treatment of schizophrenia. Hospitalization is sometimes needed initially to provide basic personal needs (safety, food, and hygiene) while acute symptoms are treated. Most patients return to the community with varying degrees of independence and with good prospects for long-term remission of symptoms.

Delusion

false belief based upon a misinterpretation of reality. It is not, like a hallucination, a false sensory perception, or like an illusion, a distorted perception. Delusions vary in intensity, and are not uncommon among substance abusers, particularly those who use amphetamines, cocaine, and hallucinogens. They also occur frequently among individuals who have been diagnosed with Alzheimer's disease , Huntington's disease , or schizophrenia , and during the manic stage of bipolar disorder (see depression ). Some common delusions include persecutory delusions, in which the individual falsely believes that others are plotting against him; delusions of thought broadcasting, where the individual believes his thoughts can be transmitted to others; delusions of thought insertion, in which the individual believes that thoughts are being implanted in his mind; and delusions of grandeur, in which the individual imagines himself an unappreciated person of great importance.

Libido

(libe´do, -bi´-) [Lat.,lust], psychoanalytic term used by Sigmund Freud to identify instinctive energy with the sex instinct. For Freud, libido is the generalized sexual energy of which conscious activity is the expression. C. G. Jung used the term synonymously with instinctive energy in general. Many psychiatrists now feel that Freud overemphasized the concept of libido as the determinant of personality development and did not adequately emphasize the results of socializing forces. The term drive is often used instead of libido but without the sexual implications of the latter. See psychoanalysis .

Extroversion and Introversion

terms introduced into psychology by Carl Jung to identify opposite psychological types. Jung saw the activity of the extrovert directed toward the external world and that of the introvert inward upon himself or herself. This general activity or drive of the individual was called the libido by Jung, who removed from the term the sexual character ascribed to it by Sigmund Freud . The extrovert is characteristically the active person who is most content when surrounded by people; carried to the neurotic extreme such behavior appears to constitute an irrational flight into society, where the extrovert's feelings are acted out. The introvert, on the other hand, is normally a contemplative individual who enjoys solitude and the inner life of ideas and the imagination. The extreme introvert's fantasies give him or her libidinal satisfactions and tend to become more meaningful to him than objective reality. Severe introversion is characteristic of autism and some forms of schizophrenia . Jung did not suggest strict classification of individuals as extroverted or introverted, since each person has tendencies in both directions, although one direction generally predominates. Influenced by Jung, Hans Eysenck conducted research on large samples of individuals, creating more objective classifications for extroversion and introversion.

Autism

(ô´tizem) , a developmental disability resulting from a neurological disorder that affects the normal functioning of the brain. It is characterized by the abnormal development of communication skills, social skills, and reasoning. Males are affected four times as often as females. Children may appear normal until around the age of 30 months. Symptoms, which vary widely in severity, include impairment in social interaction, fixation on inanimate objects, inability to communicate normally, and resistance to changes in daily routine. Characteristic traits include lack of eye contact, repetition of words or phrases, unmotivated tantrums, inability to express needs verbally, and insensitivity to pain. Behaviors may change over time. Autistic children often have other disorders of brain function; about two thirds are mentally retarded; over one quarter develop seizures. The cause of autism remains unclear, but a psychological one has been ruled out. Neurological studies seem to indicate a primary brain dysfunction, and a genetic component is suggested by a pattern of autism in some families.