Gadflies and Geniuses in the History of Gas Theory

The history of science has often been presented as a story of the achievements of geniuses: Galileo, Newton, Maxwell, Darwin, Einstein. Recently it has become popular to enrich this story by discussing the social contexts and motivations that may have influenced the work of the genius and its acceptance; or to replace it by accounts of the doings of scientists who have no claim to genius or to discoveries of universal importance but may be typical members of the scientific community at a particular time and place. In this article I consider a different type of story, which further research might reveal to be more common than we now suspect: progress stimulated by gadflies – outspoken critics who challenge the ideas of geniuses, forcing them to revise and improve those ideas, resulting in new knowledge for which the genius gets the credit while the gadfly is forgotten. This revised version was published online in June 2006 with corrections to the Cover Date.     

The learning benefits of teaching: A retrieval practice hypothesis

Teaching educational materials to others enhances the teacher's own learning of those to‐be‐taught materials, although the underlying mechanisms remain largely unknown. Here, we show that the learning‐by‐teaching benefit is possibly a retrieval benefit. Learners (a) solved arithmetic problems (i.e., they neither taught nor retrieved; control group), (b) taught without relying on teaching notes (i.e., they had to retrieve the materials while teaching; teaching group), (c) taught with teaching notes (i.e., they did not retrieve the materials while teaching; teaching without retrieval practice [TnRP] group), or (d) retrieved (i.e., they did not teach but only practised retrieving; retrieval practice group). In a final comprehension test 1 week later, learners in the teaching group, as did those in the retrieval practice group, outperformed learners in the TnRP and control groups. Retrieval practice possibly causes the learning benefits of teaching.     

The Association Between Sluggish Cognitive Tempo and Academic Functioning in Youth with Attention-Deficit/Hyperactivity Disorder (ADHD)

The purpose of the study was to evaluate the relation between Sluggish Cognitive Tempo (SCT) and academic functioning in a sample of 52 adolescents (40 males, 12 females) with Attention-Deficit/Hyperactivity Disorder (ADHD; M _age?=?13.75). This study builds on prior work by utilizing an empirically-based and psychometrically validated measure of SCT, collecting ratings of SCT from both parents and teachers, and examining associations with multiple domains of academic functioning from both the parent and teacher perspective as well as grade point average (GPA). Both SCT and DSM-IV symptoms of inattention were significantly correlated with domains of academic functioning. Multiple regression analyses demonstrated that the parent-rated SCT Slow subscale predicted overall academic functioning, organizational skills impairment, and homework problems above and beyond ADHD symptoms and child and demographic characteristics known to be associated with academics, including intelligence, academic achievement, and family income. The teacher-rated SCT Low Initiation/Persistence subscale also predicted homework problems and was the only SCT variable to predict school grades above and beyond ADHD symptoms and relevant covariates. Both the SCT Slow and Low Initiation/Persistence subscales include items related to youth seeming apathetic, unmotivated, and lacking initiative, behaviors that are strongly related to ADHD symptoms of inattention but not currently captured by the DSM-IV. Implications of these findings towards supporting the external validity of the SCT construct are discussed along with potential implications for intervention.     

Social Anxiety and Peer Relations in Early Adolescence: Behavioral and Cognitive Factors

This study investigated factors associated with social anxiety during early adolescence using multiple informants, including self and peer perspectives, teacher ratings, and direct observations. Negative social performance expectations, maladaptive coping strategies, and social skill deficits were examined as correlates of social anxiety and mediators linking social anxiety with poor peer relations. Participants were 84 middle school students (47 girls, 37 boys) over-sampled for elevated social anxiety. Analyses revealed correlations linking social anxiety with decreased peer acceptance and increased peer victimization. Path analysis indicated that negative social performance expectations and social withdrawal-disengagement accounted for the association between social anxiety and decreased peer acceptance. Social anxiety, self-directed coping strategies, and social withdrawal-disengagement were each directly linked with increased peer victimization for boys. The results replicate findings based on clinical samples, extend understanding of cognitive, social, and behavioral factors associated with social anxiety in middle school, and provide new information regarding gender differences in the correlates of social anxiety.     

An account of human “impulsivity” on self-control tasks

Three experiments examined the effects of economic constraint (time restriction—trials restriction) on adult humans' performance on concurrent chained schedules of reinforcement in which terminal links differed both in reward size and pre-reward delay levels. In the first, terminal links offered a long delay (20, 30, 40, 50 sec) followed by 2 points, or a short delay (10 sec) followed by 1 point. Initial links consisted of the same variable interval schedules for each alternative. Subjects showed a conditional sensitivity to increases in delay. Under a time constraint, there was an increasing preference for the smaller reward as the delay to the larger reward was increased, whereas under a trials constraint subjects were totally insensitive to such changes. In the second experiment, this finding was replicated using long and short periods of video game playing as large and small rewards. In the third experiment terminal link parameters remained constant (2 points after 15 sec, or 1 point immediately), but initial link parameters were manipulated (either VI 1-sec, 8-sec, or 20-sec) so that the higher relative rate of reward shifted from being associated with the small reward to being associated with the large reward. Again subjects chose differently under the two constraints. Subjects under the time constraint exhibited a preference for the small reward at all levels of initial link, but under the trials constraint subjects preferred the large reward. Subjects in the time constraint condition thus exhibited a maladaptive insensitivity to changes in the initial link duration. These findings are interpreted as supporting a miscalculation rather than a discounting interpretation of human performance on “self-control” tasks.     

Book reviews

Lea, S. E. G., Tarpy, R. M., & Webley, P. (1987). The individual in the economy. Cambridge: Cambridge University Press. Pp. 627 + xxiv. ISBN 0-521-26872-9. £39.50 (Hardback). ISBN 0-521-317014. £13.95 (Paperback).

Davey, G. & Cullen, C. (Eds.) (1988). Human operant conditioning and behaviour modifcution. Chichester: John Wiley & Sons. Pp. x + 270. ISBN 0-471-91637-4. £29.50.

Commons, M. L., Mazur, J. E., Nevin, J. A. & Rachlin, H. (Eds.). (1987), Quantitative analyses of behavior. Vol. 5: The efect of delay and of intervening events on reinforcement value. Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Pp. 344. ISBN 0-89859-800-1. £31.00.

Pearce, J. M. (1987). An introduction to animal cognition. Hove and London: Lawrence Erlbaum Associates Ltd. Pp. 328. ISBN 0-86377-0568 (hardback) 219.95; ISBN 0-86377457-6 (paperback) £9.95.

Archer, J. (1988). The behavioural biology of aggression. Cambridge: Cambridge University Press. Pp. x + 257. ISBN 0-521-34790-4. £9.95 (paperback).

Greenberg, G. and Tobach, E. (Eds.) (1987). Cognition, language, and consciousness: Integrative tevels. The T. C. Schneirla Conference Series. Volume 2. Hillsdale, NJ: Lawrence Erlbaum Associates, Inc. Pp. ix + 301. ISBN 0-89859-7224. £27.50.

Mook, D.G. (1987). Motivation: The organisation of action. New York: Norton. Pp. xxii + 586. ISBN 0-393-95474-9. £12.95 (hardback).

Frank, H. (Ed.) (1987). Man and wolf: Advances, issues and problems in captive wow research. Dordrecht: Dr. W. Junk. Pp. xviii + 439. ISBN 90-6193-614-4. £103.25 (hardback).