On the rate of stimulus occlusion during intermittent retinal stimulation

The CFF was determined with three sectored disks, each of which corresponded to one of the three rings in a Helmholtz disk. The fusion frequency is identical for all three rings of a Helmholtz disk but with the three sectored disks it was found that the rate of stimulus occlusion is a major factor in determining the CFF. It was tentatively concluded that the effect was not a consequence of different stimulus wave-forms. The phenomenon appears to have been reported late in the last century.     

Nonshared environmental influences and personality differences in adult twins

The twin design was used to examine the importance of different experiences of siblings within the family and to identify relations between twins' personality differences and their differential experiences. A sample of 161 monozygotic and 74 dizygotic twin individuals between the ages of 18 and 75 years retrospectively reported on their different experiences when growing up. The Sibling Inventory of Differential Experience (SIDE) was used for the first time with a sample of twin siblings. In addition, the twins provided self-report measures of affect and personality. In contrast to results from a sibling adoption design, this study of twins showed greater evidence for genetic variance in the SIDE scales. Nevertheless, the SIDE showed significant associations with differences in personality and affect for monozygotic twins, which reflect pure environment-behavior relations.     

Predicate-argument structure as a link between linguistic and nonlinguistic representations

We present a study wherein a severe Broca's aphasic patient was trained to learn symbols representing both pure transitive and dative predicates--predicates differing in argument structure--in a visually based artificial language (c-ViC). We found a decrease in performance when two symbols, rather than one, were used to depict these "verbs." However, this decrease in performance was more pronounced for symbols representing pure transitive verbs--those that allow only one argument structure--than for symbols representing dative verbs--those that allow two different argument structures. Also, dative "verbs" yielded better performance when they were inserted in more complex, three-argument "sentences" than when they were inserted in two-argument "sentences." The opposite pattern was found for pure transitives. These results are discussed in terms of our claim that argument structure serves as a point of connection between linguistic information and non-linguistic visual information and in terms of the possibility that argument structure entries are shaped by the form in which visual information is parsed.     

In Vivo Hippocampal Acetylcholine Release During Exposure to Acute Stress

Hippocampal extracellular acetylcholine (ACh) and choline levels were evaluated using in vivo microdialysis in male Fischer 344 rats before, during, and following an 80-min exposure to two different stress conditions. Measurements were taken in rats restrained and immersed in a water bath containing either 37 degreesC (normothermic-restraint) or 20 degreesC (cold-restraint) water. Results were compared to normothermic-freely-moving rats. Cold-restrained rats displayed decreased ACh levels during cold exposure relative to both normothermic-restrained and normothermic-freely-moving rats. By the end of the cold exposure period and following removal from cold, ACh levels had returned to near-baseline values. Normothermic-restrained rats had levels similar to those of normothermic-freely-moving rats, except for a marked increase in ACh following removal from restraint. Cold-restrained rats displayed a gradual elevation in choline levels during cold stress, followed by a gradual decline after stress termination, whereas both normothermic-restrained and normothermic-freely-moving rats displayed gradual decreases during the microdialysis session. These findings demonstrate that central cholinergic neurotransmission can be altered by the application of, and removal from, acute stressors. In addition, the results suggest a possible relationship between the magnitudes of both the stressor and its cholinergic consequences.     

Determinants of Condom Use Among High-Risk Heterosexual Adults: A Test of the Theory of Reasoned Action1

The research presents tests of traditional and augmented versions of Fishbein and Ajzen's Theory of Reasoned Action (TRA), applied to condom use among adult clients of a sexually transmitted disease clinic. In a longitudinal survey, predictor variables suggested by Ajzen and Fishbein (1980), plus gender and condom use self-efficacy, were measured at Time 1. Condom use at Time 2, 3 months later, was regressed onto these variables. The traditional TRA worked well to predict condom use intentions and behavior. Support was also found for inclusion of gender and self-efficacy in the prediction of intention to use condoms, but not behavior. Implications for interventions to increase condom use among those at high risk for AIDS and other STDs are discussed.     

Parenting stress in parents of children with attention-deficit hyperactivity disorder and parents of children with learning disabilities

Parenting a child with ADHD can challenge parenting resources and coping. Increasingly, researchers are examining the relationship between the behavior of the child with ADHD and family functioning. While studies have shown inceased parenting stress in parents of children with ADHD, these studies have compared children with ADHD to non-disabled children. This study compares reports of parenting stress among mothers of children with ADHD, mothers of children with learning disabilities and mothers of non-referred children. Results showed that parenting stress was highest for mothers of children with ADHD. Increased parenting stress was associated with child characteristics and, in particular, with externalizing behavior problems.     

An investigation of the sampling distributions of item discrimination indices

The sampling properties of four item discrimination indices (biserialr, Cook's indexB, theU–L 27 per cent index, and DeltaP) were investigated in order to ascertain their sampling properties when small samples drawn from actual test data rather than constructed data were employed. The empirical results indicated that the mean index values approximated the population values and that values of the standard deviations computed from large sample formulas were good approximations to the standard deviations of the observed distributions based on samples of size 120 or less. Goodness of fit tests comparing the observed distributions with the corresponding distribution of the product-moment correlation coefficient based upon a bivariate normal population indicated that this correlational model was inappropriate for the data. The lack of adequate mathematical models for the sampling distributions of item discrimination indices suggests that one should avoid indices whose only real reason for existence was the simplification of computational procedures.This research reported herein was performed pursuant to a contract (OE-2-10-071) with the United States Office of Education, Department of Health, Education and Welfare.     

Practice-based competencies for accreditation of and training in graduate programs in genetic counseling

In January 1996, the American Board of Genetic Counseling (ABGC) adopted 27 practice-based competencies as a standard for assessing the training of graduate students in genetic counseling. These competencies were identified and refined through a collective, narrative process that took place from January through November 1994, and included directors of graduate programs in genetic counseling, ABGC board members and expert consultants. These competencies now form the basis of the document Requirements for Graduate Programs in Genetic Counseling Seeking Accreditation by the American Board of Genetic Counseling (American Board of Genetic Counseling, 1996). The competencies are organized into four domains and are presented and discussed in this article.The Consortium includes Directors of established graduate programs in genetic counseling and members of the ABGC Board of Directors who participated in the Consensus Development Conference held in January, 1994: Diane Baker (University of Michigan/ABGC); Bonnie Baty (ABGC); Joan Burns (University of Wisconsin); Debra Collins (ABGC); Virginia Corson (ABGC); Beth Fine (Northwestern University/ABGC); Elizabeth Gettig (University of Pittsburgh); Verle Headings (Howard University); Jacqueline Hecht (University of Texas); Carl Huether (University of Cincinnati); Bonnie LeRoy (University of Minnesota); Joan Marks (Sarah Lawrence College); Anne Matthews (University of Colorado); Roberta Palmour (McGill University); Lorna Phelps (Medical College of Virginia); Kimberly Quaid (Indiana University); Joan Scott (ABGC); Ann Smith (ABGC); Helen Travers (ABGC); Judith Tsipis (Brandeis University); Ann Walker (University of California-Irvine/ABGC); Jon Weil (University of California-Berkeley); S. Robert Young (University of South Carolina); Randi Zinberg (Mount Sinai School of Medicine, New York).