Distributions of the Kullback–Leibler divergence with applications

The Kullback–Leibler divergence (KLD) is a widely used method for measuring the fit of two distributions. In general, the distribution of the KLD is unknown. Under reasonable assumptions, common in psychometrics, the distribution of the KLD is shown to be asymptotically distributed as a scaled (non‐central) chi‐square with one degree of freedom or a scaled (doubly non‐central) F. Applications of the KLD for detecting heterogeneous response data are discussed with particular emphasis on test security.     

Consolidation and translation regulation

mRNA translation, or protein synthesis, is a major component of the transformation of the genetic code into any cellular activity. This complicated, multistep process is divided into three phases: initiation, elongation, and termination. Initiation is the step at which the ribosome is recruited to the mRNA, and is regarded as the major rate-limiting step in translation, while elongation consists of the elongation of the polypeptide chain; both steps are frequent targets for regulation, which is defined as a change in the rate of translation of an mRNA per unit time. In the normal brain, control of translation is a key mechanism for regulation of memory and synaptic plasticity consolidation, i.e., the off-line processing of acquired information. These regulation processes may differ between different brain structures or neuronal populations. Moreover, dysregulation of translation leads to pathological brain function such as memory impairment. Both normal and abnormal function of the translation machinery is believed to lead to translational up-regulation or down-regulation of a subset of mRNAs. However, the identification of these newly synthesized proteins and determination of the rates of protein synthesis or degradation taking place in different neuronal types and compartments at different time points in the brain demand new proteomic methods and system biology approaches. Here, we discuss in detail the relationship between translation regulation and memory or synaptic plasticity consolidation while focusing on a model of cortical-dependent taste learning task and hippocampal-dependent plasticity. In addition, we describe a novel systems biology perspective to better describe consolidation.     

Obsessive-Compulsive Disorder in Late Life

Although obsessive-compulsive disorder (OCD) has received increasing attention, the study and treatment of OCD in late life has been neglected. The obsessions and compulsions seen with older adults do not appear to differ from the symptoms experienced by other age groups, although developmental issues might influence symptom focus (e.g., memory functioning-related obsessions). Hoarding difficulties might be prevalent in late life, although additional studies are needed. Seniors with OCD can present with comorbid psychiatric disorders, multiple general medical problems, and impaired cognitive functioning, complicating evaluation. There have not been controlled clinical trials of cognitive-behavioral therapy (CBT) for late-life OCD, although initial reports suggest older adults respond to CBT that includes age-related treatment modifications. We illustrate the challenges to assessing and treating older adults with OCD with case examples involving memory-related obsessions and clinical hoarding. The successful strategies used for adapting CBT for the treatment of late-life generalized anxiety disorder might serve as a model for advancing the study and treatment of late-life OCD.     

Attentional bias toward threat in contamination fear: overt components and behavioral correlates

Recent research suggests that an attentional bias toward threat may play a causal role in obsessive-compulsive disorder (OCD) with contamination concerns. However, the attentional components involved in this bias, as well as its behavioral correlates, remain unclear. In the present study, eye movements were recorded in individuals high and low in contamination fear (HCF, LCF, respectively) during 30-s exposures to stimulus arrays containing contamination threat, general threat, pleasant, and neutral images. HCF individuals oriented gaze toward contamination threat more often than LCF individuals in initial fixations, and this bias mediated group differences in responding to a behavioral challenge in a public restroom. No group differences were found in the maintenance of gaze on contamination threat, both in terms of initial gaze encounters, as well as gaze duration over time. However, the HCF group made shorter fixations on contamination threat relative to other image types. The implications of these findings for further delineating the nature and function of attentional biases in contamination-based OCD are discussed.     

Individual strategies and release site features determine the extent of deviation in clock-shifted pigeons at familiar sites

When homing from familiar areas, homing pigeons are able to exploit previously acquired topographical information, but the mechanisms behind this ability are still poorly understood. One possibility is that they recall the familiar release site topographical features in association with the home direction (site-specific compass orientation strategy), another that the spatial relationships among landmarks guide their route home (piloting strategy), without relying on the compass mechanism. The two strategies can be put in conflict by releasing clock-shifted birds at familiar locations, in order to highlight which is preferred. We analysed GPS tracks of clock-shifted pigeons, with familiarity controlled at each of three different release sites, and we observed that pigeons can display individual preferences for one of the two orientation strategies and that some characteristic features of the release site have an important role in determining the level of landmark-based homeward orientation.     

Carrying the Burden: Perspectives of African American Pastors on Peer Support for People with Cancer

For African Americans facing advanced cancer, churches are trusted sources of support and ideal settings to improve access to supportive care. The Support Team model enhances community support for practical, emotional, and spiritual caregiving. We report on focus groups with pastors of 23 Black Churches and explore their perspective on the Support Team model for church members with cancer. Pastors describe the needs of church members facing cancer from a holistic perspective and recognize opportunities for synergistic faith–health collaboration. The results of this study indicate potential benefits of the Support Team model in Black Churches to reduce silent suffering among individuals facing cancer.     

The black community's reactions to the 1992 los angeles riot

This article is based on field (street) interviews with a sample of 227 black community members living and/or working in South Central Los Angeles at the time of the 1992 riot. The interview instrument comprises 20 questions designed to (1) ascertain the reactions and feelings of black community members to the riot; and (2) compare a sample of black participants in the riot with nonparticipants. The participant group was found to be more frequently younger males with less education and lower income, and they were more likely to have arrest records prior to the riot than nonparticipants. Though reactions and feelings were mixed and contradictory, both groups reported an overall acceptance of the disorders. Differentials in reactions were in degree rather than in kind. Most objected to the riot in principle but concluded that collective violence “pays off.” The preriot structural facilitators (poverty, relative deprivation, unemployment, police brutality, racial discrimination, and negative police‐community relations) were similar to those found in the riot literature. Whatever the participants’ reasons and justifications for rioting might be, they present themselves as worthy protesters and freedom fighters. Unless their message is heeded and acted upon by ameliorating their adverse social, economic, and political conditions, similar riots are likely to occur.     

Subliminal understanding of negation: Unconscious control by subliminal processing of word pairs

A series of five experiments investigated the extent of subliminal processing of negation. Participants were presented with a subliminal instruction to either pick or not pick an accompanying noun, followed by a choice of two nouns. By employing subjective measures to determine individual thresholds of subliminal priming, the results of these studies indicated that participants were able to identify the correct noun of the pair – even when the correct noun was specified by negation. Furthermore, using a grey-scale contrast method of masking, Experiment 5 confirmed that these priming effects were evidenced in the absence of partial awareness, and without the effect being attributed to the retrieval of stimulus–response links established during conscious rehearsal.     

The Draw-A-Person Test and Process-Reactive Schizophrenia

The Draw-A-Pcrson test was administered to three matched groups of 32 male Ss each: reactive schizophrenics, process schizophrenics, and normal control subjects. Patients were rated for prognosis using the Premorbid Subscale of the Phillips Scale. Drawings were rated by two judges on 80 diagnostic signs culled from the literature. No signs were found to significantly differentiate reactive and process schizophrenics, and only three signs significantly differentiated normals from schizophrenics. It was concluded that a sign approach to the DAP is insensitive to the reaction-process dimension of schizophrenia, and of only limited value in differentiating between normals and schizophrenics in general.