REDUCTIONS IN SELF-INJURY PRODUCED BY TRANSCUTANEOUS ELECTRICAL NERVE STIMULATION

Transcutaneous electrical nerve stimulation is used to reduce pain but also may be useful for self-injurious behavior (SIB). In the current investigation, a microcurrent electromedical device, classified as a transcutaneous electrical nerve stimulator (TENS), was applied with a man with Down syndrome who displayed SIB that persisted in the absence of social contingencies. Although clinically significant results were not maintained, a clear difference in the rates of SIB during active and inactive TENS was observed.     

ON THE RELATION OF MANDS AND THE FUNCTION OF DESTRUCTIVE BEHAVIOR

When standard analogue functional analysis procedures produce inconclusive results in children with conversational speech, the child's mands may help to identify the function of destructive behavior. In the current investigation, functional analyses conducted with 2 children who exhibited self-injury, aggression, and property destruction were undifferentiated across conditions. Based on informal observations and school and parental report, an analysis was conducted using mands to help determine the function of the destructive behavior. Using a multielement design, the therapist's compliance with the child's mands occurred either on a fixed-ratio (FR) 1 schedule or contingent on destructive behavior. Destructive behavior occurred at high and consistent levels when reinforcement of mands was contingent on destructive behavior and at near-zero levels when reinforcement of mands occurred on the FR 1 schedule. Based on these results, a second analysis was conducted in which compliance to mands occurred only when the child appropriately requested it (i.e., functional communication training plus extinction) and, for 1 child, compliance with mands was terminated contingent upon destructive behavior (i.e., functional communication training plus response cost). For both children, the rates of destructive behavior decreased markedly. The results suggest that assessing the child's mands may be useful in decreasing destructive behavior when a functional analysis is inconclusive.     

USING A CHOICE ASSESSMENT TO PREDICT REINFORCER EFFECTIVENESS

A choice assessment has been found to be a more accurate method of identifying preferences than is single-item presentation. However, it is not clear whether the effectiveness of reinforcement varies positively with the degree of preference (i.e., whether the relative preference based on the results of a choice assessment predicts relative reinforcer effectiveness). In the current study, we attempted to address this question by categorizing stimuli as high, middle, and low preference based on the results of a choice assessment, and then comparing the reinforcing effectiveness of these stimuli using a concurrent operants paradigm. High-preference stimuli consistently functioned as reinforcers for all 4 clients. Middle-preference stimuli functioned as reinforcers for 2 clients, but only when compared with low-preference stimuli. Low-preference stimuli did not function as reinforcers when compared to high- and middle-preference stimuli. These results suggest that a choice assessment can be used to predict the relative reinforcing value of various stimuli, which, in turn, may help to improve programs for clients with severe to profound disabilities.     

Visibility distances with halogen and conventional headlights

Abstract.— Using visibility distance as a criterion, halogen and conventional continental European high and low-beam headlights were compared in a series of field experiments. On high-beam without opposing light the halogen headlights offered about 25% longer visibility distances than the conventional headlights. With both opposing cars using low-beam there was a slight advantage (<5 m) in favour of halogen headlights. The optimal dipping distance was a function of high-beam system (intensity) rather than low-beam system. Small differences in aiming, atmosphere etc. caused larger differences in visibility distance than did the headlight system.     

The intercalated reinforcement technique: Learning without differential total reinforcement between groups

An intercalated reinforcement technique is described. The method equates number of trials, response topography, sensory exposure, and frequency of reinforcement between reversal Ss overtrained on a discrimination and then trained on reversals and nonreversal Ss similarly overtrained but continued on the same discrimination. In extending previous successful work in the rat, monkeys were trained on spatial discrimination and reversal tasks in the WGTA at 50%, 75%, and 100% reinforcement in order to test the efficacy of learning by this procedure, and to compare the method with learning obtained by a more classical procedure. Learning rates were the same by both procedures. This technique, therefore, appears useful for investigating neurochemical (or other) correlates of learning unconfounded by performance or sensory effects.     

Sunscreen Safety: The Precautionary Principle, The Australian Therapeutic Goods Administration and Nanoparticles in Sunscreens

The ‘Precautionary Principle’ provides a somewhat ill-defined guide, often of uncertain normative status, for those exercising administrative decision-making power in circumstances where that may create potential risks to human health or the environment. This paper seeks to explore to what extent the precautionary principle should have been and was in fact utilised by the Australian Therapeutic Goods Administration (TGA) in its decision to approve the marketing of sunscreens containing titanium dioxide (TiO₂) and zinc oxide (ZnO) in nanoparticulate form. In particular, this article assesses to what extent better application of that principle might have altered the TGA’s decision that TiO₂ and ZnO ENPs in sunscreens do not require new safety testing, because they are considered to be functionally equivalent to their bulk counterparts.