Exploring how symptoms of attention-deficit/hyperactivity disorder are related to reading and mathematics performance: general genes, general environments

Children with attention-deficit/hyperactivity disorder (ADHD) tend to perform more poorly on tests of reading and mathematical performance than their typical peers. Quantitative genetic analyses allow for a better understanding of the etiology of ADHD and reading and mathematics outcomes, by examining their common and unique genetic and environmental influences. Analyses were conducted on a sample 271 pairs of 10-year-old monozygotic and dizygotic twins drawn from the Western Reserve Reading and Mathematics Project. In general, the results suggested that the associations among ADHD symptoms, reading outcomes, and math outcomes were influenced by both general genetic and general shared-environment factors. The analyses also suggested significant independent genetic effects for ADHD symptoms. The results imply that differing etiological factors underlie the relationships among ADHD and reading and mathematics performance. It appears that both genetic and common family or school environments link ADHD with academic performance.     

Are two heads better than one? Experimental investigations of the social facilitation of memory

The hypothesis that two people collaborating in recall would remember more than a single person was examined in a series of four experiments. All the experiments used variations on the same ‘sequential’ design where, in social conditions, people recalled alone initially and then recalled jointly in pairs: as a control for reminiscence, some people recalled alone on two separate occasions. On the second recall in all of the experiments two people always recalled more than one, but this was simply due to the independent statistical summation of two people's memories: no evidence whatsoever was found for the pairs of people generating new information that was not available to either member of the pair. This surprising result was not attributable to artefacts linked to the complexity or familiarity of stimulus material, nor was it linked to variations in people's cognitive perspectives. No evidence of social facilitation of memories was therefore found: two people recalling together certainly pool their separate memories so as to outperform individuals but the social interaction does not appear to generate previously unavailable memories.     

Animal learning of independent and correlated events

Evidence suggests that experience of a truly random presentation of a conditioned and unconditioned stimulus (CS and US) retards subsequent acquisition of a classically conditioned response when the CS and US are paired. In these studies, no events reliably predict the US during the first part of training. The present experiment demonstrated impairment of subsequent appetitive conditioning in rats following a random CS-US presentation, both when another predictive cue is present and when it is absent during this experience. Results are discussed with reference to “general attention” theory, and learned helplessness. However, the data support an interpretation in terms of learning a specific relationship between a particular CS and US.     

Concave utility,transaction costs,and risk in measuring discounting of delayed rewards

Research has consistently found that the decline in the present values of delayed rewards as delay increases is better fit by hyperbolic than by exponential delay-discounting functions. However, concave utility, transaction costs, and risk each could produce hyperbolic-looking data, even when the underlying discounting function is exponential. In Experiments 1 (N = 45) and 2 (N = 103), participants placed bids indicating their present values of real future monetary rewards in computer-based 2nd-price auctions. Both experiments suggest that utility is not sufficiently concave to account for the superior fit of hyperbolic functions. Experiment 2 provided no evidence that the effects of transaction costs and risk are large enough to account for the superior fit of hyperbolic functions.     

Nonshared environmental processes in social‐emotional development: an observational study of identical twin differences in the preschool period

Differences in mothers’ parenting behaviors toward their identical twin preschoolers were examined to identify nonshared environmental processes in social‐emotional development. The study included 62 pairs of 3½‐year‐old same‐sex identical twins. Indicators of each child’s social‐emotional development (temperament, prosocial behavior, behavior problems and noncompliance) and parenting environment (warmth and negativity, positive and negative control, responsiveness) were assessed using observers’, interviewers’, and parents’ ratings. Mothers treated their identical twins differently, and this differential treatment covaried in expected ways with identical twin differences in social‐emotional adjustment. The twin who received more supportive and less punitive forms of parenting was also higher in positive mood and prosocial behaviors and lower in negative mood and behavior problems when compared to her or his twin.     

Reviews: Books Photography

RELATIONAL PSYCHOANALYSIS: THE EMERGENCE OF A TRADITION. Edited by Stephen A. Mitchell and Lewis Aron. 514 pp. Hillsdale, NJ: The Analytic Press, 1999. $39.95. D.H. LAWRENCE AND THE PARADOXES OF PSYCHIC LIFE. By Barbara Ann Schapiro. 155 pp. Albany: State University of New York Press, 1999. $17.95. TECHNOLOGY AS MAGIC: THE TRIUMPH OF THE IRRATIONAL. By Richard Stivers. 240 pp. New York: Continuum Press. 1999. $24. REFLECTIONS ON A RAVAGED CENTURY. By Robert Conquest. 317 pp. New York: W. W. Norton & Company, 2000, $27.95. THE MYSTERIES WITHIN A SURGEON REFLECTS ON MEDICAL MYTHS. By Sherwin B. Nuland. 274 pp. New York: Simon & Schuster, 2000, $24.00. DISEASE, PAIN, AND SUICIDAL BEHAVIOR. By Elisabeth Stenager and Egon Stenager. 127 pp. New York: The Haworth Medical Press, 1998. $17.95. TRAUMA ASSESSMENTS: A CLINICIAN'S GUIDE. By E. B. Carlson. 307 pp. New York: The Guilford Press, 1997. $30. ON INFANCY AND TODDLERHOOD: AN ELEMENTARY TEXTBOOK. By David A. Freedman, M.D. 247 pp. Madison: International Universities Press, Inc., 1999. $27.95. TUESDAYS WITH MORRIE. By Mitch Albom. 192 pp. New York: Doubleday, 1997. $21. THE SORROWS OF THE QUAKER JESUS; JAMES NAYLER AND THE PURITAN CRACKDOWN ON THE FREE SPIRIT. By Leo Damrosch. 322 pp. Cambridge, MA: Harvard University Press, 1996, $39.95. THE PASTORAL CARE OF DEPRESSION: A GUIDEBOOK. By Binford W. Gilbert. 127 pp. New York: The Haworth Pastoral Press, 1998. $19.95. LEARNING DISABILITIES AND PSYCHIC CONFLICT: A PSYCHOANALYTIC CASEBOOK. By Arden Aibel Rothstein, Ph.D., and Jules Glenn, M.D. 504 pp. Madison: International Universities Press, Inc., 1999. $78. HAUNTED CHILDREN: RETHINKING MEDICATION OF COMMON PSYCHOLOGICAL DISORDERS. By Arthur F. Roemmelt, MD. 196 pp. New York: State University of New York Press, 1998. $17.95. NAVIGATING THE DEEP RIVER: SPIRITUALITY IN AFRICAN-AMERICAN FAMILIES. By Archie Smith, Jr. 181 pp. Cleveland, Ohio: United Church Press, 1997. $15.95. AL-JUNUN: MENTAL ILLNESS IN THE ISLAMIC WORLD. Edited by Ihsan Al-Issa. 382 pp. Madison: International Universities Press, 2000. $48. Witnessing the Lack of Sanctuary