Etiology is the study and investigation of the root causes of a psychological disorder so that it might be resolved. Mental illness may have biological or biochemical etiology, as well as psychosocial causative underpinnings. Most behavioral health disorders have multifactorial etiological influences.

Psychological etiology refers to the scientific investigation into the origins of a disorder that cannot be explained purely by biology or biochemistry. Etiology is complicated by the fact that most psychological disorders have more than one cause. Early etiological theories came from different schools, notably Freudian psychoanalysts and the theorists who came after Freud. Sigmund Freud (1856–1939) attributed mental or neurotic disorders to deep-seated or unconscious motivations. The unconscious played the primary role in Freud's theory of what causes neurosis. According to Freud, a person in conflict is unaware of the cause of this conflict because it lies deeply embedded in an inaccessible part of the unconscious mind. Freud speculated that childhood traumas, taboo or unacceptable feelings, or intense drives activate a defense mechanism that buries awareness deep into the unconscious. As a means of survival, a person may push such threatening thoughts and memories as far from the conscious mind as possible.

Childhood, according to Freud, is a time when many repressed motivations and defense mechanisms began to form. Without much control over their own lives, children have no way to resolve complex negative emotions, such as frustration, insecurity, or guilt. These emotions build up inside while the child's personality develops into adulthood. According to Freud, every psychological disorder from sexual dysfunction to anxiety might be explained by uncovering, through psychoanalysis, the repressed feelings a person has harbored since childhood.

The change in theory

Behavioral etiology also emerged after Freud. This theory of human nature is based on the belief that learned behaviors cause mental disorders. Ivan Pavlov (1849–1936) and B. F. Skinner (1904–90) are two famous behavioral psychologists. Behaviorists argue that the mind can be trained to respond to stimuli in various ways. A conditioned response is one that is learned when a stimulus produces a response, and the response is either positively (reward) or negatively (punishment) reinforced. A young girl, for example, is told she is cute for screeching at the sight of a spider. She learns that this screech produces a favorable response from onlookers. Over time, this learned behavior may develop into a truly paralyzing fear of spiders. Behaviorists believe that just as a person can be conditioned to respond to a stimulus in a particular way, that same person can be conditioned to respond differently. In other words, more appropriate behavior can be learned, which is the basis for behavioral therapy.

Contemporary approaches to therapy, including the existential and cognitive approaches, have led psychology away from depicting mental illnesses as emerging from a singular root cause. For example, clinical psychologists generally search for a complexity of issues that stem from emotional, psychosexual, social, cultural, or existential causes. The cognitive approach, developed by Aaron Beck (1921–), attempts to readapt behavioral responses through a rational process that demands honesty and discipline to undo fears and anxieties.

Psychologists, psychiatrists and behavioral health science research scientists have recognized that much of mental illness has complex biopsychosocial etiology. Many research studies have resulted in the refinement of prescription medications that alter a person's biochemistry to prevent or control various illnesses, including bipolar illness, mood disorders and schizophrenia. Neuropathology, or damage to brain tissue, can also serve as a biological cause of psychological disorders. Genetic research has been conducted to determine the causes of certain disorders at the DNA level. Researchers have been working for decades to isolate a gene that contains the program for many types of schizophrenia.

Crucial to the treatment of any disorder is an understanding of its possible causes. Psychologists need to narrow the etiology of a disorder before they identify the most efficient and effective course of treatment.

See also Clinical psychology ; Cognitive behavior therapy; Cognitive therapy ; Psychotherapy .



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