Neuropathology of Rett syndrome

Rett Syndrome is unlike any other pediatric neurologic disease, and its clinical-pathologic correlation can not be defined with standard histology techniques. Based on hypotheses suggested by careful clinical observations, the nervous system of the Rett child has been explored utilizing morphometry, golgi preparations, computerized tomography, magnetic resonance imaging, chemistry, immunocytochemistry, autoradiography, and molecular biologic techniques. From these many perspectives we conclude that Rett syndrome is not a typical degenerative disorder, storage disorder, nor the result of gross malformation, infectious or neoplastic processes. There remain regions of the brain that have not been studied in detail but the available data suggest that the neuropathology of Rett syndrome can be summarized as follows: the Rett brain is small for the age and the height of the patient; it does not become progressively smaller over three to four decades; it has small dendritic trees in pyramidal neurons of layers III and V in selected lobes (frontal, motor, and temporal); it has small neurons with an increased neuronal packing density; it has an immature expression of microtubular protein-2 and cyclooxygenase; it exhibits a changing pattern of neurotransmitter receptors with an apparent reduction in many neurotransmitters, possibly contributing to some symptomatology. A mutation in Mecp2 causes this unique disorder of brain development. Neuronal mosaicism for normal and mutated Mecp2 produces a consistent phenotype in the classic female patient and a small brain with some preserved islands of function, but with an inability to support hand use and speech. This paper summarizes our current observations about neuropathology of Rett syndrome. MRDD Research Reviews 2002;8:72-76.     

Reduction Invariance and Prelec's Weighting Functions

Within the framework of separable utility theory, a condition, called reduction invariance, is shown to be equivalent to the 2-parameter family of weighting functions that Prelec (1998) derived from the condition called compound invariance. Reduction invariance, which is a variant on the reduction of compound gambles, is appreciably simpler and more easily testable than compound invariance, and a simpler proof is provided. Both conditions are generalized leading to more general weighting functions that include, as special cases, the families of functions that Prelec called exponential-power and hyperbolic logarithm and that he derived from two other invariance principles. However, of these various families, only Prelec's compound-invariance family includes, as a special case, the power function, which arises from the simplest probabilistic assumption of reduction of compound gambles. Copyright 2001 Academic Press.     

Parents who report using illicit drugs: findings and implications from the DRUGNET study

In recent years, a national discussion has emerged concerning what parents should tell their children about their own past drug use. DRUGNET is an ongoing, on-line survey of successful, healthy, adults who occasionally use illicit drugs. This paper reviews data from a subset of this survey, namely, those respondents who were parents with self-reported use of at least one illicit drug. The sample (n = 325) was predominantly white men who reported having above average education and household incomes. Their mental health as measured by the General Well-being Schedule was similar to the national norm. Respondents reported using drugs to manage parental stress and expressed concerns over how to communicate with their children and legal risks related to their own drug use. The limitations and the implications of these data are discussed.     

From the interpersonal to the international: understanding commitment to the "war on terror"

Applying constructs from the investment model used traditionally to understand interpersonal commitment, the present investigation seeks to elucidate social cognitive antecedents of commitment to the war on terror waged by the United States. In Study 1, satisfaction with, investments in, and alternatives to the war on terror predict levels of commitment to the war beyond several important control variables. In Study 2, levels of satisfaction with, investments in, and alternatives to the war are experimentally manipulated. The highest levels of commitment to the war are observed among participants exposed to a high satisfaction, high investment, and low alternatives scenario, and the lowest levels are among those exposed to a low satisfaction, low investment, and high alternatives scenario. These results support broadening the targets of commitment normally considered within the context of the investment model and suggest applying relational models to understanding broader societal concerns.     

Taxometric analysis of the antisocial features scale of the personality assessment inventory in federal prison inmates

The Antisocial Features (ANT) scale of the Personality Assessment Inventory (PAI) was subjected to taxometric analysis in a group of 2,135 federal prison inmates. Scores on the three ANT subscales-Antisocial Behaviors (ANT-A), Egocentricity (ANT-E), and Stimulus Seeking (ANT-S)-served as indicators in this study and were evaluated using the following taxometric procedures: mean above minus below a cut (MAMBAC), maximum eigenvalue (MAXEIG), and latent mode factor analysis (L-Mode). Objective and subjective evaluation of the results revealed consistent support for a dimensional interpretation of latent structure across the di ferent taxometric procedures as well as across gender, race, and security level. As a dimensional construct, antisocial personality disorder arranges respondents along one or more quantitative dimensions (degree of antisociality), rather than assigning them to qualitatively distinct categories (antisocial or not antisocial).     

School readiness and later achievement

Using 6 longitudinal data sets, the authors estimate links between three key elements of school readiness--school-entry academic, attention, and socioemotional skills--and later school reading and math achievement. In an effort to isolate the effects of these school-entry skills, the authors ensured that most of their regression models control for cognitive, attention, and socioemotional skills measured prior to school entry, as well as a host of family background measures. Across all 6 studies, the strongest predictors of later achievement are school-entry math, reading, and attention skills. A meta-analysis of the results shows that early math skills have the greatest predictive power, followed by reading and then attention skills. By contrast, measures of socioemotional behaviors, including internalizing and externalizing problems and social skills, were generally insignificant predictors of later academic performance, even among children with relatively high levels of problem behavior. Patterns of association were similar for boys and girls and for children from high and low socioeconomic backgrounds.     

Detection of malingering of psychiatric disorder with the personality assessment inventory: an investigation of criminal defendants

To assess the diagnostic accuracy of the Personality Assessment Inventory (PAI; Morey, 1991) Validity scales for the detection of malingered psychiatric disorders, we divided a sample of criminal defendants referred for forensic evaluation by the federal courts into malingering and not malingering groups based on their performance on the Structured Interview of Reported Symptoms (Rogers, Gillis, & Bagby, 1990). Logistic regression analyses (LGAs) revealed that there were no differences between the malingering and not malingering groups with respect to age, race, years of education, history of drug abuse, or number of previous felony convictions. LGA with malingering versus not malingering as the criterion revealed that the PAI Negative Impression Management (NIM) scale but not the Rogers Discriminant Function (RDF; Rogers, Sewell, Morey & Ustad, 1996) nor the Malingering index (MAL; Morey, 1996) significantly differentiated the malingering from the not malingering group. Receiver operating characteristics analyses demonstrated acceptable sensitivity and specificity for the NIM scale but not the RDF scale or the MAL index. We discuss the results in terms of the suggested cutoff scores for the PAI Validity scales in detecting criminal defendants who are attempting to feign psychiatric disorder.     

Culture in the context of intercultural negotiation.

This study explores culture's effect on behaviors and outcomes in intercultural negotiation and examines how those effects are moderated by role. Eighty U.S. and international students took part in a previously developed negotiation task (Pruitt, 1981) and completed Hui and Triandis's (1986) individualism‐collectivism (INDCOL) scale. Negotiation interactions were coded for information sharing, offers, and distributive tactics. Findings show that a negotiation dyad's collectivism is positively associated with higher joint profit. The effects of culture on both communication behaviors and joint outcomes, however, differ by role of the negotiator. In particular, seller collectivism has larger and more consistent effects on communication behavior and joint profit than buyer collectivism. Results support a ‘culture in context’ perspective of negotiation that takes into account negotiator qualities, contextual and structural features of the negotiation, and mediating processes in addition to cultural values.