Promoting response variability and stimulus generalization in martial arts training

The effects of reinforcement and extinction on response variability and stimulus generalization in the punching and kicking techniques of 2 martial arts students were evaluated across drill and sparring conditions. During both conditions, the students were asked to demonstrate different techniques in response to an instructor's punching attack. During baseline, the students received no feedback on their responses in either condition. During the intervention phase, the students received differential reinforcement in the form of instructor feedback for each different punching or kicking technique they performed during a session of the drill condition, but no reinforcement was provided for techniques in the sparring condition. Results showed that both students increased the number of different techniques they performed when reinforcement and extinction procedures were conducted during the drill condition, and that this increase in response variability generalized to the sparring condition.     

Visual neglect in the first weeks after a stroke in the right hemisphere

The aim of the study was to characterize symptoms of visual neglect among patients who recently survived a stroke in the right hemisphere (RH), and to contribute to the understanding of change in symptoms during the first months after a RH stroke. Thirteen patients with a RH stroke and twenty controls were assessed by using standard neglect tests. Five patients were followed up by repetitive test sessions during the next four months. To assess more subtle symptoms, reaction-time (RT) measures derived from an experimental cue-target paradigm were included in the final test session. A high frequency of neglect symptoms was documented at the first test session. The changes in performance during the first weeks were characterized by a high inter-individual as well as a high intra-individual variability. Although the remission rate on standard tests was high in the follow-up study, the RT measures indicated sustained symptoms of visual extinction in all patients. The long-term implication of the changes of neglect symptoms during the first weeks after a stroke and signs of sustained symptoms of visual extinction calls for further longitudinal studies including a larger group of patients.     

The effects of antecedent interventions and extinction on toddlers' compliance during transitions

We compared the effects of two antecedent strategies commonly used in early childhood settings to increase compliance during activity transitions: a warning condition, in which children were informed of the transition 2 min before it began, and a condition in which children were allowed access to a toy during the transition. Both antecedent interventions were ineffective when implemented alone; however, when these strategies were combined with extinction, improvements in compliance were observed for all children.     

The use of an escape contingency and a token economy to increase food acceptance

Escape (termination of a meal) and token-based differential reinforcement of alternative behavior were used as reinforcement to increase acceptance of food. Using a changing criterion design, the number of bites accepted and consumed was gradually increased to 15 bites per meal. These data suggest that, in some cases, escape may be a potent reinforcer for food acceptance.     

On the relative contributions of positive reinforcement and escape extinction in the treatment of food refusal

We compared the effects of positive reinforcement alone, escape extinction alone, and positive reinforcement with escape extinction in the treatment of the food and fluid refusal of 4 children who had been diagnosed with a pediatric feeding disorder. Consumption did not increase when positive reinforcement was implemented alone. By contrast, consumption increased for all participants when escape extinction was implemented, independent of the presence or absence of positive reinforcement. However, the addition of positive reinforcement to escape extinction was associated with beneficial effects (e.g., greater decreases in negative vocalizations and inappropriate behavior) for some participants.     

Parental assessment and treatment of food selectivity in natural settings

This study evaluated the effects of a parent-conducted functional analysis and treatment consisting of differential reinforcement of an alternative behavior, escape extinction, and demand fading on food selectivity in a young child with autism. Increases in food acceptance at home and in a restaurant were obtained.     

Recency, repeatability, and reinforcer retrenchment: an experimental analysis of resurgence

Four experiments were conducted with pigeons to assess the experimental conditions necessary for the occurrence of resurgence. The general procedure consisted of the following conditions: Condition 1--reinforcement of key pecking; Condition 2--reinforcement of treadle pressing and concurrent extinction of key pecking; and Condition 3--the resurgence condition wherein resurgence was defined as the recovery of key pecking. In Experiments 1 and 2, the resurgence condition was conventional extinction. The effect of recency on resurgence magnitude was examined in Experiment 1 by manipulating the number of sessions of Condition 2, above. Resurgence was not a function of recency with the parameters used. Repeating the three conditions revealed resurgence to be a repeatable effect in Experiment 2. In Experiment 3, a variable-time schedule was in effect for the resurgence condition. Resurgence was not produced by response-independent food delivery. In Experiment 4, the resurgence condition was a variable-interval schedule for treadle pressing that arranged a lower reinforcement rate than in Condition 2 (92% reduction in reinforcers per minute). Resurgence was lower in magnitude relative to conventional extinction, although resurgence was obtained with 2 out of 3 pigeons. The results are discussed in terms of the variables controlling resurgence and the relations between behavioral history, resurgence, and other forms of response recovery.     

DISTINGUISHING BETWEEN EXTINCTION AND PUNISHMENT EFFECTS OF RESPONSE BLOCKING: A REPLICATION

Lerman and Iwata (1996) described a method for distinguishing between sensory extinction and punishment effects of response blocking on self-injurious behavior maintained independent of social contingencies. Results of their study suggested that blocking decreased the self-injurious hand mouthing of their participant via punishment. The current replication of these procedures with the self-injurious eye poking of a woman with developmental disabilities produced patterns of responding indicating that, for this participant, blocking functioned as an extinction procedure.     

ON THE EFFECTS OF NONCONTINGENT DELIVERY OF DIFFERING MAGNITUDES OF REINFORCEMENT

We conducted a parametric analysis of response suppression associated with different magnitudes of noncontingent reinforcement (NCR). Participants were 5 adults with severe or profound mental retardation who engaged in a manual response that was reinforced on variable-ratio schedules during baseline. Participants were then exposed to NCR via multielement and reversal designs. The fixed-time schedules were kept constant while the magnitude of the reinforcing stimulus was varied across three levels (low, medium, and high). Results showed that high-magnitude NCR schedules produced large and consistent reductions in response rates, medium-magnitude schedules produced less consistent and smaller reductions, and low-magnitude schedules produced little or no effect on responding. These results suggest that (a) NCR affects responding by altering an establishing operation (i.e., attenuating a deprivation state) rather than through extinction, and (b) magnitude of reinforcement is an important variable in determining the effectiveness of NCR.     

THE USE OF NONCONTINGENT ESCAPE TO REDUCE DISRUPTIVE BEHAVIORS IN CHILDREN WITH SPEECH DELAYS

Noncontingent escape (NCE) was used to reduce disruptive behavior in 3 children during regularly scheduled speech therapy sessions. Results showed rapid decreases in disruptive behavior and accompanying increases in compliance across children. Findings suggest that speech therapists with little expertise in behavior analysis can effectively implement NCE.