The theory of behaviorism, first established by the work of the famous Russian physiologist Ivan Pavlov (1849–1936) and greatly expanded in the 1920s by the American psychologist John B. Watson (1878–1958), became the first of many theories from the ranks of psychologists to compete with the all-encompassing nature of the theory of psychoanalysis promoted by the Austrian neuropsychiatrist Sigmund Freud (1856–1939). Following the lead of Hall, later psychologists moved beyond just education counseling and aptitude testing to create clinical psychology, in which the theories of psychology served as tools in mental health care. This innovation was bitterly contested within the profession, and it is no accident that members of the medical profession, under such leaders as Freud, rather than psychologists, were the first to extensively develop twentieth-century mental health care. Psychology, unsure of itself as a science, slowly made the transition into healing.

The psychologist B. F. Skinner (1904–1990) carried the banner of behaviorism that had been left by Watson. As a strict behaviorist, Skinner believed that nurture dictated all action and that nature played no role. He rejected free will or any notion of unconscious motivation. Mainstream psychologists did not accept his theory, but the extreme nature of his stance and the articulate manner in which he presented his ideas continue to make him a useful standard to measure later psychological theories against.

The American psychologist Carl R. Rogers (1902–1987) advocated client-centered therapy beginning in the 1940s, a form of therapy in which therapists urged clients to find their own paths to health. The therapist was a facilitator and was not to impose her or his own values on the client. This positive ideal of the individual as being able to self-heal became a characteristic of humanistic psychology, as did the ideal of self-realization. Rogers used the term client, rather than patient, to emphasize the nonmedical and noncoercive nature of his treatment. The American psychologist Abraham H. Maslow (1908–1970) also promoted humanistic psychology with his theory of self-actualization, developed in the 1950s and early 1960s. Maslow’s theory postulated a pyramid of needs, with basic physiological requirements at the bottom, love and esteem in the center, and self-actualization as the capstone. Unless restrained by social norms or neuroses, people naturally strive to self-actualize once the other needs are fulfilled, though few ever achieve that pinnacle. Other humanistic psychological flavors of psychotherapy became prominent in the 1960s and 1970s, such as logotherapy, Gestalt therapy, existential analysis, self-directed encounter groups, and addiction recovery clinics.

Only after World War II did clinical psychology rise to become a significant scientific and social force, complementing and competing with the medically based discipline of psychiatry, especially in the United States. Universities opened counseling centers that offered educational counseling and psychotherapy. Mainline Protestant religions began to incorporate training in clinical psychology into their pastoral education programs, turning ministers and pastors into professionally trained psychotherapists. Religious leaders have always had a therapeutic role in society, though this embracing of modern psychology was ironic, in that surveys showed that of all the scientific and scholarly disciplines, psychologists and psychiatrists harbored the most negative attitudes toward organized religion, with the exception of philosophers. With the middle class growing more prosperous, psychotherapists inspired by Rogers, Freud, and other theorists began to offer psychotherapy to more than just institutionalized patients and the wealthy. Especially in the United States, psychotherapy became popular, and society at large became psychologized, using psychological terms and viewing relationships through pop psychology. Movies, books, magazine articles, seminars, and popular discourse spread the message.

Almost unnoticed amid the expansion of the field was a 1952 article by the English psychologist Hans J. Eysenck (1916–1997), who reported that after reviewing twenty-four studies he found no empirical evidence that neurotic patients who received psychotherapy recovered any more frequently than those not treated by a psychotherapist. Studies found that the form of psychological treatment often did not make a difference, and even indicated that at times, psychotherapy made patients, or clients, worse than if they had not been treated at all by a psychological professional. Appalled by the lack of scientific rigor in the selection of therapeutic modalities, the psychologists Sol Garfield (1918–) and Allen E. Bergin (1934–) edited a leading textbook, the Handbook of Psychotherapy and Behavior Change: An Empirical Analysis (1971), which went through multiple editions, in an effort to alert their colleagues to this problem.

So how are clients who seek psychotherapy healed? Multiple researchers have indicated that healing occurs when the psychotherapist creates an environment of trust and expertise, forming a therapeutic alliance. The psychotherapist’s personal characteristics of understanding, empathy, and concern are the major factors in healing. The psychiatrist Jerome Frank (1909–) has pointed out that this alliance does not even have to be a face-to-face relationship. Ironically enough, a self-help book can also provide many of these same elements to a lesser degree and thus serve as a healing mechanism for the reader. This form of healing, whether based on verbal conversation or through a book, only works if the client accepts the causal explanations of the psychotherapist; the talking cure requires the patient’s cooperation.

Without a doubt, psychopharmacological drugs can have a significant impact regardless of the cognitive cooperation of the patient. Doses of lithium carbonate have been successfully used to treat bipolar disorder, also called manic-depressive psychosis, in which the sufferer alternates between periods of manic euphoria and depression. The antidepressant Prozac, the first of the selective serotonin reuptake inhibitors (SSRIs), introduced in 1986, works by interfering with the reabsorption of the neurotransmitter serotonin in the brain. Prozac is also used to treat obsessive-compulsive disorder and bulimia nervosa, and is even used by some mentally healthy people as a psychological cosmetic to enhance their productivity. At the end of the century, very few psychological disorders were readily treated by drug therapy, despite a few outstanding successes. The social and cultural context of the disturbed person still determined most of a given problem’s parameters.

The spirit of the 1960s looked to liberate and empower the victims of society wherever they were found. The awful conditions in mental hospitals drew the sympathy and indignation of social activists, and the activists also questioned the prerogative of psychiatrists to institutionalize people against their will. In the late 1960s, a vigorous antipsychiatry movement began, launching a well-meaning deinstitutionalization process. The asylums quickly emptied their patients onto the streets to be cared for by community-based treatment programs. Most of these programs have failed and homelessness has increased.

By the 1970s, the older rigid schools of psychoanalysis and behaviorism had begun to fade. Humanistic psychology and eclecticism have increasingly become the norm, though no unified psychological paradigm has emerged. Eclectic psychotherapists reject rigid adherence to any particular school of psychology or treatment modality. They choose from among a menu of options based on the needs of each individual client. The emphasis on self-realization and breaking social and psychological barriers within feminism also played a role in breaking the hold of the older schools. The notable book Toward a New Psychology of Women (1976), by the feminist psychiatrist Jean Baker Miller, helped promote the idea that psychologists had neglected to develop an accurate understanding of women.

Genuine advances in psychology are hard to achieve because human subjects are difficult to study and because repeatability is hard. There have been notable achievements. The experimental psychologist Harry F. Harlow (1905–1981) used studies of maternal deprivation with rhesus monkeys to show that love is a primary drive for primates and humans. He changed the way that modern psychologists look at the need for affection between adults and the need for affectionate mother-child relations, though his methods would not pass an ethics review board today. The Swiss-born psychiatrist Elisabeth Kübler-Ross (1926–2004) found that terminally ill people and people in mourning pass through a series of five stages: denial and isolation, anger, bargaining, depression, and then acceptance. She also promoted the hospice movement and contributed to thanatology, the study of death.

The zoologist-turned-sexologist Alfred Kinsey (1894–1956) published two books, Sexual Behavior in the Human Male (1948) and Sexual Behavior in the Human Female (1953), that astonished Americans with their revelations that what was considered sexually deviant behavior, such as masturbation and homosexuality, was much more widespread than commonly assumed. Later critics found that Kinsey’s scientific techniques inevitably led to biased results, overstating the incidence of different sexual practices in an effort to promote his social agenda. The detailed physiological and psychological work of the physician William H. Masters (1915–2001) and the psychologist Virginia Johnson (1925–) established a firm medical basis for sexology and the emergence of clinical sex therapy.

The study of primates by Jane Goodall (1934–), Dian Fossey (1932–1985), and others made important contributions to how we view human behavior. A form of behaviorism has been revived with the study of sociobiology and evolutionary psychology by the zoologists Edward O. Wilson (1929–) and Richard Dawkins (1941–). The role of dreams and their role in consciousness have always intrigued cognitively oriented psychologists. The discovery in 1953 that dreams correspond to rapid eye movement (REM) and that most other mammals also experience REM has raised many questions with no satisfactory answers.

Intelligence tests, often giving a single numeric intelligence quotient (IQ) score, were first created in the early part of the twentieth century. They fell into disfavor after the 1960s, when social activists objected to racist or social assumptions made in the tests, and when the realization began to grow that intelligence was a multifaceted concept, not easily reduced to a single number. In the 1990s, the idea of emotional intelligence (EQ) became common, though it was not quantified as a number; rather it was seen as a characteristic that indicated who would be more likely to be successful in life, regardless of their IQ score. A high EQ indicates the ability of an individual to control and channel emotions to serve long-term goals.

The 1980s saw the rise of the recovered-memory movement, based on the theory that the memory of traumatic events like sexual abuse is repressed. Some victims came forward with stories of abuse that they remembered years after the abuse, either as a result of psychotherapy or prompted by a flashback. These repressed memories were often vague or ambiguous, and the number of specific details usually increased with time. The issue of repressed memories was always controversial, but in the 1990s neurologists and psychologists who specialized in how memory actually works argued that there was not a mechanism for the kind of repression that the recovered-memory movement postulated. At times, sometimes using hypnosis, zealous psychotherapists had led their patients to believe that abuse had occurred when it really had not.

See also Bioethics; Cognitive Science; Dawkins, Richard; Feminism; Fossey, Dian; Goodall, Jane; Harlow, Harry F.; Kinsey, Alfred C.; Kübler-Ross, Elisabeth; Masters, William H., and Virginia Johnson; Medicine; National Institutes of Health; Religion; Rogers, Carl R.; Skinner, B. F.; Sociobiology and Evolutionary Psychology; Wilson, Edward O.