Ellipses on the surface of a picture

Shapes on the surface of a perspective picture may be misperceived. Subjects picked a match for an ellipse depicting the circular top of a cylinder. The top was depicted as tilted forward from 5 degrees to 85 degrees, generating a series of ellipses on the picture surface. The matches were biased towards a circle over a wide range of midrange tilts, which suggests that, influenced by features of perspective, they were seen as in-between the shape on the surface and the shape they depicted.     

The application of the first order system transfer function for fitting the 3-arm radial maze learning curve

A mathematical model is described based on the first order system transfer function in the form Y=B3∗exp(−B2∗(X−1))+B4∗(1−exp(−B2∗(X−1))), where X is the learning session number; Y is the quantity of errors, B2 is the learning rate, B3 is resistance to learning and B4 is ability to learn. The model is tested in a light-dark discrimination learning task in a 3-arm radial maze using Wistar and albino rats. The model provided good fits of experimental data under acquisition and reacquisition, and was able to detect strain differences among Wistar and albino rats. The model was compared to Rescorla-Wagner, and was found to be mutually complementary. Comparisons with Tulving’s logarithmic function and Valentine’s hyperbola and the arc cotangent functions are also provided. Our model is valid for fitting averaged group data, if averaging is applied to a subgroup of subjects possessing individual learning curves of an exponential shape.     

Similarities and differences between traumatic and emotional memories: review and directions for future research

The authors review theory and empirical research on the characteristics of memories for traumatic versus emotional events, with the goal of bringing together the cognitive and clinical perspectives on this issue. They consider the most important approaches to the study of traumatic and emotional memory and summarize the results of recent studies that have compared autobiographical recollections of traumatic and nontraumatic emotional experiences (positive and negative), either in nonclinical or clinical samples. Overall, findings from the current empirical literature are inconsistent. Although some researchers have found that traumatic memories are retrieved differently than are emotional memories, others have demonstrated that the phenomenological characteristics of these memory types are highly similar. The authors discuss methodological issues that could help researchers to interpret the inconsistencies found in the empirical findings. Last, they suggest possible directions for future research that may advance researchers' knowledge of memory, trauma, and emotion.     

Vladimir Solov'ëv as `A Mirror of the Russian Counter-Revolution'

In this narrative analysis oftwo Soviet dissertations in philosophy Idiscuss the role of Solov'ëv as one of themajor characters in the Soviet academicnarration of Russian philosophy: I show how theauthors (Turenko and Spirov) cope with thenecessity of criticizing Solov'ëv from theMarxist position and protect him from Westernscholars as the latter attempted to reviseRussian philosophy. I also discuss the way inwhich this requirement both to criticize andprotect is represented in the dissertations inwhich the strong Marxist posture and loyalty tocommunist doctrine corresponded to the authors'belief that Solov'ëv was a greatphilosopher who made mistakes, although hisphilosophy remains a part of Russia's culturalheritage. The main conclusion is that in spiteof their vision of the world as split into thecommunist and bourgeois camps, both authors tryto avoid straightforward Manichean assessmentsand, in 60s and 70s, were keen to find as manypositive elements in Solov'ëv's philosophyas possible.     

Cognitive Neuropsychology of HIV-Associated Neurocognitive Disorders

Advances in the treatment of the human immunodeficiency virus (HIV) have dramatically improved survival rates over the past 10 years, but HIV-associated neurocognitive disorders (HAND) remain highly prevalent and continue to represent a significant public health problem. This review provides an update on the nature, extent, and diagnosis of HAND. Particular emphasis is placed on critically evaluating research within the realm of cognitive neuropsychology that aims to elucidate the component processes of HAND across the domains of executive functions, motor skills, speeded information processing, episodic memory, attention/working memory, language, and visuoperception. In addition to clarifying the cognitive mechanisms of HAND (e.g., impaired cognitive control), the cognitive neuropsychology approach may enhance the ecological validity of neuroAIDS research and inform the development of much needed novel, targeted cognitive and behavioral therapies. The research described was supported by MH73419 and MH62512 from the National Institutes of Health. The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of the Navy, Department of Defense, nor the United States Government.     

Blind man draws using diminution in three dimensions

Can the principle of convergence in three spatial dimensions be reflected in drawings by the congenitally blind? A man who had been totally blind since birth was asked to draw scenes such as a tabletop with three cubes receding to the observer’s left side. He used converging lines to show the tops of the cubes receding in depth. He drew the cubes to the left smaller than the cube in front of the observer. He drew faces of cubes to the left with tilted lines, pointing to below the front face of the cube in front. The result approximates three-point perspective. We note that the directions of objects from a vantage point in touch converge much as they do in vision.     

Foreshortening, convergence and drawings from a blind adult

Esref is a congenitally totally blind man, practiced in drawing. He was asked to draw solid and wire cubes situated in several places around his vantage point. He used foreshortening of receding sides and convergence of obliques, in approximate one-point perspective. We note that haptics provides information about the direction of objects--the basis of perspective.     

Test-retest reliability of component process variables within the Hopkins Verbal Learning Test-Revised

Emerging data support the construct validity of component process variables of learning and memory within the Hopkins Verbal Learning Test-Revised (HVLT-R; Brandt & Benedict, 2001); however, the test-retest reliabilities of such measures are heretofore largely unknown. This study reveals generally modest-to-low 1-year test-retest stability for several key HVLT-R component process variables (e.g., semantic clustering) in 41 healthy, younger adults. These findings are discussed in relation to issues of clinical practice and research design in neuropsychological assessment.     

Are Christian politics possible? A Kierkegaardian perspective

This paper provides a rereading of Søren Kierkegaard's attack upon Christendom in light of his theory of spheres of existence to examine whether Christian politics are possible after Kierkegaard. Talking of Christian politics makes sense only in the esthetic and the religious spheres of existence. However, Kierkegaard argues that politics worthy of the title Christian are impossible. Either such politics are simply Christendom far removed from New Testament Christianity, or Christian politics are faced with the paradox of existing before God and cannot proceed.