Self-Injurious Behavior: Behavior in which persons hurt or harm themselves without the motive of suicide or of sexual deviation.Self Mutilation: The act of injuring one's own body to the extent of cutting off or permanently destroying a limb or other essential part of a body.Pemoline: A central nervous system stimulant used in fatigue and depressive states and to treat hyperkinetic disorders in children.Intellectual Disability: Subnormal intellectual functioning which originates during the developmental period. This has multiple potential etiologies, including genetic defects and perinatal insults. Intelligence quotient (IQ) scores are commonly used to determine whether an individual has an intellectual disability. IQ scores between 70 and 79 are in the borderline range. Scores below 67 are in the disabled range. (from Joynt, Clinical Neurology, 1992, Ch55, p28)Education of Intellectually Disabled: The teaching or training of those individuals with subnormal intellectual functioning.Aversive Therapy: A treatment that suppresses undesirable behavior by simultaneously exposing the subject to unpleasant consequences.Behavior Therapy: The application of modern theories of learning and conditioning in the treatment of behavior disorders.Stereotyped Behavior: Relatively invariant mode of behavior elicited or determined by a particular situation; may be verbal, postural, or expressive.Reinforcement (Psychology): The strengthening of a conditioned response.Lesch-Nyhan Syndrome: An inherited disorder transmitted as a sex-linked trait and caused by a deficiency of an enzyme of purine metabolism; HYPOXANTHINE PHOSPHORIBOSYLTRANSFERASE. Affected individuals are normal in the first year of life and then develop psychomotor retardation, extrapyramidal movement disorders, progressive spasticity, and seizures. Self-destructive behaviors such as biting of fingers and lips are seen frequently. Intellectual impairment may also occur but is typically not severe. Elevation of uric acid in the serum leads to the development of renal calculi and gouty arthritis. (Menkes, Textbook of Child Neurology, 5th ed, pp127)Extinction, Psychological: The procedure of presenting the conditioned stimulus without REINFORCEMENT to an organism previously conditioned. It refers also to the diminution of a conditioned response resulting from this procedure.Reinforcement, Social: The strengthening of a response with a social reward such as a nod of approval, a parent's love or attention.Escape Reaction: Innate response elicited by sensory stimuli associated with a threatening situation, or actual confrontation with an enemy.Token Economy: A practice whereby tokens representing money, toys, candy, etc., are given as secondary reinforcers contingent upon certain desired behaviors or performances.Punishment: The application of an unpleasant stimulus or penalty for the purpose of eliminating or correcting undesirable behavior.Restraint, Physical: Use of a device for the purpose of controlling movement of all or part of the body. Splinting and casting are FRACTURE FIXATION.Reinforcement Schedule: A schedule prescribing when the subject is to be reinforced or rewarded in terms of temporal interval in psychological experiments. The schedule may be continuous or intermittent.Suicide, Attempted: The unsuccessful attempt to kill oneself.Aggression: Behavior which may be manifested by destructive and attacking action which is verbal or physical, by covert attitudes of hostility or by obstructionism.Autistic Disorder: A disorder beginning in childhood. It is marked by the presence of markedly abnormal or impaired development in social interaction and communication and a markedly restricted repertoire of activity and interest. Manifestations of the disorder vary greatly depending on the developmental level and chronological age of the individual. (DSM-V)Social Environment: The aggregate of social and cultural institutions, forms, patterns, and processes that influence the life of an individual or community.Attention: Focusing on certain aspects of current experience to the exclusion of others. It is the act of heeding or taking notice or concentrating.Universities: Educational institutions providing facilities for teaching and research and authorized to grant academic degrees.Motivation: Those factors which cause an organism to behave or act in either a goal-seeking or satisfying manner. They may be influenced by physiological drives or by external stimuli.Trichotillomania: Compulsion to pull out one's hair.Behavior, Animal: The observable response an animal makes to any situation.Prevalence: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.