Preload and isometric force variability

Two experiments are reported, which examined the relative contributions of preload (resting force level), change of force, and the time taken to achieve the force in determining isometric force variability. The findings showed that change of force is the strongest determiner of peak force variability but that preload and time to peak force have smaller though systematic effects. A formula that predicts peak force variability is proposed, with preload as an additive effect to the ratio between the change of force level and the square root of time to peak force. These findings confirm that these three impulse variables are significant in predicting force variability and that the impact of rate of force on peak force variability is nonlinear.     

Automation bias: decision making and performance in high-tech cockpits

Automated aids and decision support tools are rapidly becoming indispensable tools in high-technology cockpits and are assuming increasing control of"cognitive" flight tasks, such as calculating fuel-efficient routes, navigating, or detecting and diagnosing system malfunctions and abnormalities. This study was designed to investigate automation bias, a recently documented factor in the use of automated aids and decision support systems. The term refers to omission and commission errors resulting from the use of automated cues as a heuristic replacement for vigilant information seeking and processing. Glass-cockpit pilots flew flight scenarios involving automation events or opportunities for automation-related omission and commission errors. Although experimentally manipulated accountability demands did not significantly impact performance, post hoc analyses revealed that those pilots who reported an internalized perception of "accountability" for their performance and strategies of interaction with the automation were significantly more likely to double-check automated functioning against other cues and less likely to commit errors than those who did not share this perception. Pilots were also lilkely to erroneously "remember" the presence of expected cues when describing their decision-making processes.     

A renaissance in residential behavior analysis? A historical perspective and a better way to help people with challenging behavior

After a slow start, the popularity of applied behavior analysis for people with severe behavior problems peaked in the 1970s and was then battered down by the effects of methodological behaviorism, the aversives controversy, overregulation, and the inherent limitations of congregate living. Despite the ethical, technical, and conceptual advancements in behavior analysis, many people with challenging behavior live in futile environments in which the behavior analyst can only tinker. A radically behavioristic approach has become available that has the power to change these conditions, to restore the reciprocity necessary for new learning, and to bring residential behavior analysts more in contact with the contingencies of helping and teaching. The approach is consistent with alternatives that behaviorists have suggested for years to improve the image and effectiveness of applied behavior analysis, although it will take the behaviorist far from the usual patterns of practice. Finally, the approach promotes its own survival by promoting access to interlocking organizational contingencies, but its antithetical nature presents many conceptual and practical challenges to agency adoption.     

International publication trends in the experimental analysis of behavior

The present paper assessed international publication trends in the experimental analysis of behavior by recording the geographical origin of the first authors of articles in the Journal of the Experimental Analysis of Behavior (JEAB), the Journal of Applied Behavior Analysis (JABA), and The Behavior Analyst (TBA). Five international categories were identified: Australasia, Europe, Latin America, the Middle East, and North America. A cooperative category was also employed to assess the number of publications with authors from different international categories. First, the percentage and number of international articles published in JEAB, JABA, and TBA are presented. Second, a more detailed analysis of the publication rates within the international categories is presented. The number and rate at which new authors from the categories appeared and the percentage of articles published by different authors are also presented. Some limitations of the review and suggestions for increasing international participation in behavior analysis are outlined.     

Sexuality education and young people's sexual behavior: a review of studies

Sexuality education for children and young adults is one of the most heavily debated issues facing policy-makers, national AIDS program planners, and educators, provoking arguments over how explicit education materials should be, how much of it there should be, how often it should be given, and at what age instruction should commence. In this context, the World Health Organization's Global Program on AIDS' Office of Intervention Development and Support commissioned a comprehensive literature review to assess the effects of HIV/AIDS and sexuality education upon young people's sexual behavior. 52 reports culled from a search of 12 literature databases were reviewed. The main purpose of the review is to inform policy-makers, program planners, and educators about the impact of HIV and/or sexuality education upon the sexual behavior of youth as described in the published literature. Of 47 studies which evaluated interventions, 25 reported that HIV/AIDS and sexuality education neither increased nor decreased sexual activity and attendant rates of pregnancy and sexually transmitted diseases (STDs). 17 reported that HIV and/or sexuality education delayed the onset of sexual activity, reduced the number of sex partners, or reduced unplanned pregnancy and STD rates Only 3 studies found increases in sexual behavior associated with sexuality education. Inadequacies in study design, analytic techniques, outcome indicators, and the reporting of statistics are discussed.     

The effects of periodic visual occlusion on ball catching

Four experiments were conducted to examine the effects of periodic visual occlusion on one-handed ball catching. Tennis balls were projected one at a time over distances of 8-12 m, and liquid-crystal visual occlusion spectacles provided intermittent vision by opening and closing the lens shutters at different frequencies. As well as frequency, we manipulated duty cycle, or the proportion of time that the lenses were open. Generally, catching performance deteriorated as frequency was reduced. Although longer visual samples (i.e., increased duty cycle) mediated this effect to some extent, the most potent variable was the time between visual samples; performance deteriorated rapidly when this interval was greater than 80 ms (i.e., 10 Hz with 20-ms lens open times). Presumably this occurred because subjects had difficulty integrating visual information separated by longer temporal intervals.     

A transformation of self-discrimination response functions in accordance with the arbitrarily applicable relations of sameness, more than, and less than

In Experiment 1, 2 experimental subjects were given pretraining of nonarbitrary relations that brought their responses under the control of four contextual stimuli; same, opposite, more than, and less than. One control subject was not exposed to this pretraining. The 2 pretrained subjects and the 3rd nonpretrained subject then received training in six arbitrary relations, the following four relations being the most critical: same/A1-B1, same/A1-C1, less than/A1-B2, more than/A1-C2. All 3 subjects were then tested for seven derived relations, the following three relations being the most important: same/B1-C1, more than/B1-C2, less than/B1-B2. The 2 pretrained subjects, but not the nonpretrained subject, showed the derived relations. One of the stimuli (B1) from the relational network and two novel stimuli (X1 and X2) were then used to train three different self-discrimination responses on three complex schedules of reinforcement. That is, all 3 subjects were trained to pick X1 if they had not emitted a response, to pick B1 if they had emitted one response only, and to pick X2 if they had emitted two responses only. The 2 pretrained subjects, but not the nonpretrained subject, showed the predicted transformation of self-discrimination response functions in accordance with the relations of sameness, more than, and less than (i.e., no response, pick B2; one response only, pick C1; and two responses only, pick C2). In Experiment 2, 2 new subjects were employed, and the arbitrary relational training and testing phases were modified to control for a procedural artifact that may have contributed to the results of the first experiment. Experiment 2 replicated the findings of Experiment 1. The pattern of results support the utility of a relational frames approach to understanding derived stimulus relations.     

Effects of test anxiety, ego stress, and attentional skills training on arithmetic reasoning: An experimental evaluation of a brief counseling strategy

Abstract Two hundred forty high school students (120 male and 120 female) in India performed a moderately difficult multiple choice Arithmetic Reasoning task after undergoing short-term (40 minutes) cognitive treatment in the form of Attentional Skills Training. A 2 × 2 × 2 (Test Anxiety x Attentional Skills Training x Stress) design with separate analysis for boys and girls indicated these results: with intervention the high anxiety subjects under ego stress conditions, compared to their high-anxious control, low-anxious ego stress, or low-anxious control counterparts, reported the maximum significant improvement in performance on the Arithmetic Reasoning test. The low-anxiety subjects performed consistently well with or without treatment or stress conditions. The findings shed new light on the attentional theory of test anxiety, and it was reasoned that long-term effects of cognitive treatment be studied by using varied performance tasks (difficulty level controlled) on different gender and age groups across cultures.