Sensory Extinction: A procedure for eliminating self-stimulatory behavior in developmentally disabled children

This study was designed to investigate the role of sensory reinforcement in the motivation of self-stimulation. If self-stimulatory behavior is maintained by its sensory consequences, such as the proprioceptive, auditory, or visual stimulation it produces, then such behavior should extinguish when those sensory consequences are not permitted. The present study introduces a new procedure, Sensory Extinction, in which certain sensory consequences are masked or removed, to examine whether self-stimulation is operant behavior maintained by sensory reinforcement. The effectiveness of Sensory Extinction was assessed by a reversal design for each of three autistic children, and the results showed the following. First, self-stimulation reliably extinguished when a certain sensory consequence was removed, then increased when that consequence was permitted. This was replicable within and across children. Second, different Sensory Extinction procedures were required for different self-stimulatory behaviors, since the sensory reinforcers supporting them were idiosyncratic across children. Finally, regarding clinical gains, the data suggest that Sensory Extinction may be a relatively convenient and rapid alternative for the treatment of self-stimulation. The present findings extend the efficacy of extinction as a behavior-modification technique to instances in which the reinforcer is purely sensory. The implications of these results for the treatment of other forms of deviant behavior are discussed.     

Self-consciousness,self-report of aggressiveness,and aggression

Private self-consciousness consists of attending to one's thoughts, feelings, and motives. Public self-consciousness consists of attending to oneself as a social object. The effect of dispositional self-consciousness on the accuracy of self-reports was studied in research on aggression. High- and low-private self-conscious subjects rated their own aggressiveness. Several weeks later their aggressive behavior was objectively measured. The correlation between self-report of aggressiveness and aggressive behavior was significantly higher for high-than for low-private self-conscious subjects. The correlation between self-report and behavior was unaffected by public self-consciousness. The implications of these findings for self-consciousness theory and personality dispositions are discussed.     

An inexpensive digital millisecond timer and event counter

A simple circuit for a digital millisecond timer and event counter is described. The total cost of the unit including all components, a power supply, and an enclosure is less than $30. Daily use in simple reaction time experiments has demonstrated the reliability of the design.     

A technique for converting from intravenous drug self-administration to liquid reinforcement

A rapid inexpensive technique for changing from intravenous drug self-administration (DSA) to liquid reinforcement is described. Utilizing a standard peristaltic-type infusion pump typically used in DSA experiments and a specially designed drinking cup, the changeover from intravenous DSA to liquid reinforcement can be accomplished in a few minutes at a cost of less than $10.     

Developmental trends in distractibility: Is absolute or proportional decrement the appropriate measure of interference?

Since baseline performance varies with age, diminished interference effects found with increasing age do not provide evidence for a developmental trend in distractibility unless their relationship to baseline performance is known. In the present study, baseline difficulty was varied in two speeded classification experiments to investigate whether interference effects due to irrelevant information could best be characterized by absolute or proportional decrement models. In Experiment 1, first graders, third graders, and adults sorted cards on the basis of square size, both in the presence and absence of extraneous stimulus information. In Experiment 2, first graders and adults sorted cards on the basis of the density of a regular array of dots and two kinds of irrelevant information were used. Robust interference effects were found which declined with age. Manipulating discriminability of the relevant stimulus dimension resulted in large changes in sorting time, but interference effects did not vary with baseline difficulty. These results were interpreted as strongly supporting both an absolute decrement model and a developmental trend in distractibility.     

A set-theoretic random utility model of choice behavior

A random utility model of choice was developed by combining the basic ideas of the well-known theories of Thurstone and Restle. The new model has exactly the same number of free parameters as Tversky's Elimination-by-Aspects model. Furthermore, both models were found to fit, with equal accuracy, the data reported by Rumelhart and Greeno, and Tversky. It was concluded that although the two theories are not identical, they may be difficult to discriminate empirically.