BEHAVIORAL PERSISTENCE AND VARIABILITY DURING EXTINCTION OF SELF-INJURY MAINTAINED BY ESCAPE

The self-injurious escape behavior of a developmentally disabled adult was treated with extinction. Results of a reversal design showed substantial bursts of responding when extinction was introduced and reintroduced: self-injury remained at a variable and elevated rate for some time before stable, low rates were observed. Data on aggression, a nontarget behavior during both baseline and treatment, showed a pattern similar to that seen for self-injury during the extinction conditions.     

Treatment of escape-maintained aberrant behavior with escape extinction and predictable routines

We evaluated the effects of two daily activity schedules on 2 participants' rates of aberrant behavior and their compliance. Functional analysis identified the operant function of the participants' aberrant behaviors to be escape from tasks. Participants were taught to use stimuli contained in daily schedules, and were tested based on a modified stimulus-equivalence model that consisted of flash cards and activity schedules comprised of words or photographs that corresponded to the participants' daily activities. On pretests, the participants demonstrated simple and conditional discriminations with the photographs but not with the printed stimuli. A time-delay procedure was used to teach the participants to name the flash cards. Following training, the printed activity schedules corresponded to lower rates of problem behavior and higher rates of compliance than the photographic activity schedules. Performance on posttests indicated the establishment of functional classes of stimuli involving the flash cards and activity schedules even though this type of correspondence was not directly trained.     

B.F. SKINNER AND THE GRAND INQUISITOR

Abstract. B.F. Skinner allures us with the possibilities of turning the stones of materialistic rewards into the bread of human values. He tempts us by assuring success in achieving our goals through behavioral science, if only we give up our autonomy. He offers the power of complete control over our behaviors, on condition that we relinquish responsibility for our lives to a technological elite. Is B. F. Skinner a flesh-and-blood Grand Inquisitor? This essay tries to persuade the reader that Skinner's offers are worth considering.     

Preventing antisocial behavior in the schools

Multiple correlates and determinants of antisocial behavior within the home, community, and school are reviewed. Due to the school's pivotal role in our society, an emphasis is placed on how our schools contribute to antisocial behavior, and what educators can do to prevent anti-social behavior and related attendance problems. A variety of contextual factors and setting events within our schools appear to be major contributors to antisocial behavior, and some of the same factors identified within the schools also have been identified within the home. These setting events, rather than quick restrictive fixes, must be given more attention if we are to provide safe school environments-environments that durably prevent antisocial behavior and related attendance problems.     

Prevalence of the extinction burst and its attenuation during treatment

Although extinction has been an effective treatment for a variety of behavior disorders, its use may be associated with several adverse side effects, the most common being an initial increase in the frequency of the target response, called an "extinction burst." We attempted to determine the prevalence of the extinction burst in applied research and its possible attenuation with other operant procedures. An analysis of 113 sets of extinction data indicated that bursting may not be as common as previously assumed (it occurred in 24% of the cases) and may be less likely when extinction is implemented with alternative procedures rather than as the sole intervention (bursting was evident in 12% of the former cases and 36% of the latter).     

INCREASING COMPLEX SOCIAL BEHAVIORS IN CHILDREN WITH AUTISM: EFFECTS OF PEER-IMPLEMENTED PIVOTAL RESPONSE TRAINING

Two children with autism were taught to engage in a variety of complex social behaviors using peer-implemented pivotal response training (PRT), a set of procedures designed to increase motivation and promote generalization. Typical peers were taught to implement PRT strategies by modeling, role playing, and didactic instruction. After training, peers implemented the procedures in the absence of direct supervision in a classroom environment. After the intervention, both children with autism maintained prolonged interactions with the peer, initiated play and conversations, and increased engagement in language and joint attention behaviors. In addition, teachers reported positive changes in social behavior, with the largest increases in peer-preferred social behavior. Further, these effects showed generality and maintenance. Implications of these findings are discussed.     

REDUCING ESCAPE BEHAVIOR AND INCREASING TASK COMPLETION WITH FUNCTIONAL COMMUNICATION TRAINING,EXTINCTION AND RESPONSE CHAINING

The effects of functional communication training, extinction, and response chaining on 3 subjects' escape-maintained aberrant behavior were evaluated using a multielement design. Functional communication training consisted of teaching subjects a verbal response that was functionally equivalent to their aberrant behavior. Subjects initially were allowed to escape from a task contingent on the trained verbal response. In subsequent treatment phases, escape was contingent on the trained verbal response plus the completion of the specified number of steps in the task (response chaining). The number of steps was increased until a subject completed the task to obtain a break. Results showed that the treatment reduced rates of aberrant behavior and that the chaining procedure was effective in decreasing the availability of escape.     

Effects of a variable-ratio conditioning history on sensitivity to fixed-interval contingencies in rats.

We investigated the possibility that human-like fixed-interval performances would appear in rats given a variable-ratio history (Wanchisen, Tatham, & Mooney, 1989). Nine rats were trained under single or compound variable-ratio schedules and then under a fixed-interval 30-s schedule. The histories produced high fixed-interval rates that declined slowly over 90 sessions; differences as a function of the particular history were absent. Nine control animals given only fixed-interval training responded at lower levels initially, but rates increased with training. Despite differences in absolute rates, rates within the intervals and postreinforcement pauses indicated equivalent development of the accelerated response patterns suggestive of sensitivity to fixed-interval contingencies. The finding that the histories elevated rates without retarding development of differentiated patterns suggests that the effective response unit was a burst of several lever presses and that the fixed-interval contingencies acted on these units in the same way as for single responses. Regardless of history, the rats did not manifest the persistent, undifferentiated responding reported for humans under comparable schedules. We concluded that the shortcomings of animal models of human fixed-interval performances cannot be easily remedied by including a variable-ratio conditioning history within the model.     

Food-deprivation effects on punished schedule-induced drinking in rats.

Food-deprived rats (at 80% of their free-feeding weights) were exposed to a fixed-time 60-s schedule of food-pellet presentation and developed schedule-induced drinking. Lick-dependent signaled delays (10 s) to food presentation led to decreased drinking, which recovered when the signaled delays were discontinued. A major effect of this punishment contingency was to increase the proportion of interpellet intervals without any licks. The drinking of yoked control rats, which received food at the same times as those exposed to the signaled delay contingency (masters), was not consistently reduced. When food-deprivation level was changed to 90%, all master and yoked control rats showed decreases in punished or unpunished schedule-induced drinking. When the body weights were reduced to 70%, most master rats increased punished behavior to levels similar to those of unpunished drinking. This effect was not observed for yoked controls. Therefore, body-weight loss increased the resistance of schedule-induced drinking to reductions by punishment. Food-deprivation effects on punished schedule-induced drinking are similar to their effects on food-maintained lever pressing. This dependency of punishment on food-deprivation level supports the view that schedule-induced drinking can be modified by the same variables that affect operant behavior in general.