A long-term case study of analysis,response suppression,and treatment maintenance involving life-threatening pica

Behavioral assessment and intervention strategies used to treat chronic, life-threatening pica in an institutionalized, 16-year-old male with profoundly retarded collateral self-injurious and aggressive conduct, are described and evaluated. Thirty-minute observation sessions, conducted under baited contitions, revealed that bait saliency and the absence of caregiver supervision were discriminative for high rates of pica. Oral delivery of response-contingent lemon juice suppressed pica to near zero rates, while a procedural package incorporating delivery of water mist contingent on response-antecedant wandering contributed to further reductions in pica. Considerable suppression was maintained for approximately 18 months, with administration by paraprofessional staff. Data spanning nearly four years indicated that pica suppression was primarily a function of the introduction, maintenance, and withdrawal of aversive contingencies, rather than of concurrent schedules of positive reinforcement. Positive and negative side effects, and ethical questions associated with the use of aversive stimuli in treating life-threatening behavior, are discussed.