Second to fourth digit ratio and numerical competence in children

The ratio between the 2nd and 4th fingers (2D:4D)-a potential proxy for prenatal testosterone (T) exposure-shows a sex difference, with males usually having lower mean values; the latter potentially indicates higher prenatal T exposure. We studied relations between 2D:4D and competencies in the domains of counting, number knowledge, and visual-number representation in 73 children aged 6-11 years. Significant negative correlations between numerical performance in all of these areas and right and left hand 2D:4D ratios were found for boys but not girls. To the extent that 2D:4D ratios reflects prenatal exposure to T, the implications are (i) high prenatal T may be associated with better performance on some basic numerical measures for boys, and (ii) prenatal exposure to T may affect boys and girls differently with respect to some numerical competencies.     

Brain activation during semantic processing in autism spectrum disorders via functional magnetic resonance imaging

Language and communication deficits are core features of autism spectrum disorders (ASD), even in high-functioning adults with ASD. This study investigated brain activation patterns using functional magnetic resonance imaging in right-handed adult males with ASD and a control group, matched on age, handedness, and verbal IQ. Semantic processing in the controls produced robust activation in Broca's area (left inferior frontal gyrus) and in superior medial frontal gyrus and right cerebellum. The ASD group had substantially reduced Broca's activation, but increased left temporal (Wernicke's) activation. Furthermore, the ASD group showed diminished activation differences between concrete and abstract words, consistent with behavioral studies. The current study suggests Broca's area is a region of abnormal neurodevelopment in ASD, which may be linked with semantic and related language deficits frequently observed in ASD.     

Health-Risking Social Behaviors: Moving Forward

The National Institute of Mental Health (NIMH) and the National Institute on Drug Abuse (NIDA) have a long history of supporting investigator-initiated research and research training to enhance the scientific understanding of and effective interventions for a range of problems associated with youth violence. New technologies are emerging and basic research has promise for increasing our understanding of how biological factors operate in conjunction with other factors to contribute to violent behavior, psychopathology, and drug abuse. This article describes emerging areas and directions for research in this important area of public health.The views expressed are those of the authors and do not necessarily represent those of the National Institute of Mental Health, the National Institute on Drug Abuse, the National Institutes of Health, the Department of Health and Human Services, or the U.S. Government.     

How two causes are different from one: The use of (un)conditional information in Simpson's paradox

In a causally complex world, two (or more) factors may simultaneously be potential causes of an effect. To evaluate the causal efficacy of a factor, the alternative factors must be controlled for (or conditionalized on). Subjects judged the causal strength of two potential causes of an effect that covaried with each other, thereby setting up a Simpson's paradox--a situation in which causal judgments should vary widely depending on whether or not they are conditionalized on the alternative potential cause. In Experiments 1 (table format) and 2 (trial-by-trial format), the subjects did conditionalize their judgments for one causal factor on a known alternative cause. The subjects also demonstrated that they knew what information was needed to properly make causal judgments when two potential causes are available. In Experiment 3 (trial-by-trial), those subjects who were not told about the causal mechanism by which the alternative cause operated were less likely to conditionalize on it. However, the more a subject recognized the covariation between the alternative cause and the effect, the more the subject conditionalized on it. Such behavior may arise from the interaction between bottom-up and top-down processing.     

Implicit /explicit memory versus analytic/nonanalytic processing: Rethinking the mere exposure effect

In studies of the mere exposure effect, rapid presentation of items can increase liking without accurate recognition. The effect on liking has been explained as a misattribution of fluency caused by prior presentation. However, fluency is also a source of feelings of familiarity. It is, therefore, surprising that prior experience can enhance liking without also causing familiarity-based recognition. We suggest that when study opportunities are minimal and test items are perceptually similar, people adopt an analytic approach, attempting to recognize distinctive features. That strategy fails because rapid presentation prevents effective encoding of such features; it also prevents people from experiencing fluency and a consequent feeling of familiarity. We suggest that the liking-without-recognition effect results from using an effective (nonanalytic) strategy in judging pleasantness, but an ineffective (analytic) strategy in recognition. Explanations of the mere exposure effect based on a distinction between implicit and explicit memory are unnecessary.     

Personality disorders associated with substance use among American and Greek adolescents

A study was conducted to investigate the association between personality disorder (PD) symptomatology and substance use among adolescents in community settings in the United States and Greece. The Structured Clinical Interview for DSM-IV Personality Disorders and the Adolescent Health Behavior Survey were completed by 37 male and 84 female adolescents, ages 15 to 18, who were recruited from an adolescent medical clinic and schools in and near New York City (n = 71) and Heraklion, Greece (n = 50). Results indicated that: (1) adolescents with PDs reported more frequent alcohol consumption during the past year than did those without PDs; (2) adolescents with borderline PD reported more cigarette smoking and heavy alcohol consumption than did those without borderline PD; (3) adolescents with antisocial PD symptomatology reported greater alcohol, cigarette, and illicit drug use than did those without antisocial PD symptomatology; and (4) although more American (30%) than Greek (4%) adolescents reported illicit substance use, differences were not observed in the prevalence of alcohol use, cigarette use, or personality disorders as a function of nationality.     

Assessing secure base behavior in adulthood: development of a measure,links to adult attachment representations,and relations to couples' communication and reports of relationships

A focus on the secure base phenomenon creates a framework for exploring the function of the attachment system in adulthood. Engaged couples (N = 157) were videotaped in a problem-solving interaction and assessed using the Secure Base Scoring System (SBSS), a system based on Ainsworth's analyses of infant-parent secure base use and support. Study 1 showed behavior was significantly related to representations assessed with the Adult Attachment Interview (M. Main & R. Goldwyn, 1994). In Study 2, the interactions were independently scored with the Rapid Marital Interaction Coding System (RMICS; R. E. Heyman & D. Vivian, 1993), a communication-based system. The SBSS predicted relationship variables beyond the RMICS, especially for women. Results indicate that the secure base phenomenon provides a cogent perspective on adult attachment behavior.     

Exploring racism

Whilst the concept of 'race' has no basis in genetics or biology, the dynamics of racism pervade all aspects of modern life--including the consulting room. In this paper the relationship between a white therapist and a black patient is explored through an unbidden thought and a verbal slip that occurred in the course of the therapy. The amplification and examination of these unwanted 'slips' are used to shed light on the subtleties of the effects of difference in colour on the relationship. It is argued here that the interaction reflects and illuminates the asymmetrical relationship between 'black' and 'white' in modern-western society. This is then considered using the concepts of the cultural unconscious and social unconscious as ways of understanding the tenacity of racism in ourselves.     

Are false memories more difficult to forget than accurate memories? The effect of retention interval on recall and recognition

What is the effect of retention interval on accurate and false recollection in the Deese, Roediger, and McDermott (DRM) procedure? Previous research has suggested that false recall is more persistent than accurate recall, but the recognition results have been inconsistent. In two parametric studies, we tested recall and recognition for the same DRM lists, over retention intervals that ranged from no delay to a 2-month delay. We found that accurate and false memory were diminished by increases in retention interval, false memory persistence was present for recall and recognition, greater persistence for false memory than for accurate memory was more readily observed for recall than recognition, and the highthreshold (Pr), signal detection (d’), and nonparametric (A’) recognition measures differed in their sensitivity for detecting change. The effect of retention interval on accurate and false memory is consistent with expectations from fuzzy trace theory. In the DRM procedure, truth is not more memorable than fiction.     

Statistical inference for a linear function of medians: confidence intervals,hypothesis testing,and sample size requirements

When the distribution of the response variable is skewed, the population median may be a more meaningful measure of centrality than the population mean, and when the population distribution of the response variable has heavy tails, the sample median may be a more efficient estimator of centrality than the sample mean. The authors propose a confidence interval for a general linear function of population medians. Linear functions have many important special cases including pairwise comparisons, main effects, interaction effects, simple main effects, curvature, and slope. The confidence interval can be used to test 2-sided directional hypotheses and finite interval hypotheses. Sample size formulas are given for both interval estimation and hypothesis testing problems.