Methylphenidate Does Not Modify the Impact of Response Frequency or Stimulus Sequence on Performance and Event-Related Potentials of Children with Attention Deficit Hyperactivity Disorder

Twenty-six children with attention deficit/hyperactivity disorder (ADHD) participated in a double-blind trial consisting of 2 consecutive weeks each of placebo and methylphenidate (M = 26.92 mg/day = 0.78 mg/kg/day). As expected, stimulant therapy resulted in moderate weight loss, increased somatic complaints, and teacher and parent reports of reduced inattentiveness, aggression, and oppositionality. In both phases of the trial, patients were tested in a choice reaction time task assessing two aspects of the task that presumably affect response selection: response frequency (ratio of targets/nontargets = 25/75 vs. 50/50) and stimulus sequence (alternations vs. repetitions). Both manipulations yielded expected results on performance and event-related potentials (ERPs). Stimulant treatment increased accuracy and speed among younger children and curtailed variability of reaction time for the sample as a whole. However, methylphenidate did not affect ERPs. In combination, the results imply that the enhancement of performance by methylphenidate does not involve the demands of response selection examined in this study.     

Mate choice turns cognitive

Evolutionary psychology has revolutionized research on human mate choice and sexual attraction in recent years, combining a rigorous Darwinian framework based on sexual selection theory with a loosely cognitivist orientation to task analysis and mechanism modelling. This hard Darwinian, soft computational approach has been most successful at revealing the adaptive logic behind physical beauty, demonstrating that many sexual cues computed from face and body shape are not arbitrary, but function as reliable indicators of phenotypic and genetic quality. The same approach could be extended from physical to psychological cues if evolutionary psychology built stronger ties with personality psychology, psychometrics and behavioral genetics. A major challenge for mate choice research is to develop more explicit computational models at three levels, specifying: (1) the perceptual adaptations that register sexual cues given sensory input, (2) the judgment adaptations that integrate multiple cues into assessments of overall attractiveness, and (3) the search strategies that people follow in trying to form mutually attracted pairs. We describe both recent efforts and possible extensions in these directions. The resulting confluence between evolutionary principles, cognitive models and game-theoretic insights can put mate choice research at the vanguard of an emerging `evolutionary cognitive science' more concerned with domain-specific mental adaptations than with domain-general intelligence.     

Wittgenstein: time for a new philosophical practice

Continental Philosophy Review - This essay gathers Wittgenstein's comments and considerations concerning the philosophical investigation of time. Time here serves as an exemplary instance of...     

Dual diagnosis: Clinical issues in substance abuse treatment

Dual diagnosis within the context of alcohol and substance abuse has become the focus of considerable interest, particularly when related to anxiety and depression. Depressive symptomatology is frequently associated with substance abuse and chemical dependency and numerous studies report a high concordance with these diagnostic entities and major affective disorder (Galanter,Casteneda, & Ferman, 1988). Depressive symptoms are also related to post treatment of alcohol and substance abuse with reported occurrences of 75 percent occurring with patients who have experienced relapse (Biedermann, Newcome, & Sprich, 1991).     

Childhood trauma in victims of the Armenian earthquake

Childhood victims of the Armenian earthquake have shown numerous diagnostic indicators of traumatization and stress. Examined are clinical data which address advances in understanding diagnostic indicators and resulting psychopathology in childhood victims of natural disasters. Presented is a review of current theory about the processing of traumatization in children, as well as case vignettes, and recommendations for further research.     

PROGRAMMING FOR SURVIVAL: A MEETING SYSTEM THAT SURVIVES 8 YEARS LATER

Effective and useful interventions often deteriorate when researchers withdraw their direct supervision. We tested the survival of an intervention designed to produce effective weekly meetings in a student housing cooperative without direct researcher supervision. Chairperson performance, proposals completed per hour, and ratings of chairperson performance all increased when resident staff used a training manual, prompting checklist, and performance reviews. Eight years of follow-up revealed continuing high levels of meeting effectiveness. This study demonstrates a methodology for the direct observation and experimental analysis of intervention survival.     

Psychoeducation and managed care: Clinical issues for the 1990s

Managed care has challenged mental health professionals to develop more efficient ways of addressing patient care needs. Psychoeducational programs, for patients and their families, have emerged as a medium by which relevant education and mutual support can be provided to participants. A review of the literature, a comprehensive model of psychoeducation, and the advantages of such models within the managed care program are offered. Also addressed are issues and import, treatment and research considerations.     

TRUTH,PERMANENCE, AND THE REGULATION OF BELIEF: LOEB'S CARTESIAN ARGUMENT1

In this paper I outline an argument which Louis Loeb attributes to Descartes, which attempts to ground the epistemic priority of reason over sense-perception in the brute psychological irresistibility of the former. I claim that the position thus ascribed to Descartes collapses into a crude form of idealism, and attempt to pinpoint precisely the flaw in the argument which gives rise to this collapse. I finish by suggesting that the same flaw might be apparent in Philip Pettit's recent development of the notion of response-dependent concepts.