Differential roles of the frontal and parietal cortices in the control of saccades

Although externally as well as internally-guided eye movements allow us to flexibly explore the visual environment, their differential neural mechanisms remain elusive. A better understanding of these neural mechanisms will help us to understand the control of action and to elucidate the nature of cognitive deficits in certain psychiatric populations (e.g. schizophrenia) that show increased latencies in volitional but not visually-guided saccades. Both the superior precentral sulcus (sPCS) and the intraparietal sulcus (IPS) are implicated in the control of eye movements. However, it remains unknown what differential contributions the two areas make to the programming of visually-guided and internally-guided saccades. In this study we tested the hypotheses that sPCS and IPS distinctly encode internally-guided saccades and visually-guided saccades. We scanned subjects with fMRI while they generated visually-guided and internally-guided delayed saccades. We used multi-voxel pattern analysis to test whether patterns of cue related, preparatory and saccade related activation could be used to predict the direction of the planned eye movement. Results indicate that patterns in the human sPCS predicted internally-guided saccades but not visually-guided saccades in all trial periods and patterns in the IPS predicted internally-guided saccades and visually-guided saccades equally well. The results support the hypothesis that the human sPCS and IPS make distinct contributions to the control of volitional eye movements.     

Preliminary Psychometric Evidence for Distinct Affective and Cognitive Mechanisms Mediating Contamination Aversion

Contamination aversion is implicated in a range of psychological disorders, such as obsessive-compulsive disorder and health anxiety. Despite broad implications, the core mechanisms mediating contamination aversion are mixed and have not clearly been elucidated. The present studies are psychometric investigations of the components of contamination aversion and tests of the different mechanisms that mediate the severity of these components. In Study 1, items from existing measures of contamination aversion were compiled into one measure and administered to a large sample of nonclinical participants (N?=?1,286). Exploratory factor analyses demonstrated a two-factor structure, with one factor comprised of items related to intrinsically (direct) contaminated objects and the other factor comprised of items related to extrinsically (indirect) contaminated objects. In Study 2, items were added and confirmatory factor analyses supported a two-factor model in another large nonclinical sample (N?=?612). In Study 3 (N?=?471), structural modeling demonstrated distinct relations between the two factors and affective and cognitive constructs. Affective constructs related more to aversions toward more directly contaminated objects and situations while cognitive constructs related more to aversions toward more indirectly contaminated objects and situations. The present studies help clarify and articulate the unique roles of cognition and affect in specific contamination aversions, and, as such, have important implications for conceptual modeling of contamination-related psychopathology.     

A comparison of two report formats for alcohol and caffeine use

Abstract

The present study compared two different methods of assessing alcohol and caffeine use in a community sample of adults over a one-year period. Daily reporting of beer/wine intake was more stable over time and showed higher correspondence with Quantity-frequency measures than daily reporting of hard liquor use. Coffee and tea use showed high temporal stability and good alternate form reliability, though a tendency to underreport typical use of coffee use was observed. The psychometric properties of substance use measures appear to vary with type of beverage consumed and report format.     

The Field of Science and Religion as Natural Philosophy

“Natural philosophy” is an important term from the history of science because it was used to describe the study of nature during medieval and early modern Europe. This article gives an overview of the history of natural philosophy, since the use and eventual disuse of the term helps one to understand the emergence of modern science. Following a suggestion by the historian of science Peter Dear, I argue that the term deserves to be rehabilitated because it draws attention to the complexities of scientific theorizing. The article concludes with an argument that the field of science and religion should be seen as an updated version of natural philosophy.     

The Emerging Church as Corporatization’s Line of Flight

ABSTRACT

In the United States and elsewhere, many religious organizations have adopted structures, mechanisms, and ideologies that can be understood through the concept of corporatization. More than a process, corporatization creates a schema through which social relationships are structured and particular values and beliefs are emphasized (particularly, the valorization of the consumer). The authors of the present article draw on Gilles Deleuze and Felix Guattari’s conceptualization of ‘lines of flight’ to illustrate how the Emerging Church, a new religious movement, has leveraged the discontinuities within corporatization. The participants of this movement do so in order to resist institutionalizing systems that rigidify and indoctrinate participants. The authors use ethnographic field methods to demonstrate how Emerging Church participants rely on the tropes of ‘messiness’ and ‘conversation’ to embrace a radical contingency, to foster dialogue, and to avoid adopting rigid, rationalized systems of meaning.     

Dependence on Visual Feedback During Motor Skill Learning in Alzheimer's Disease

Three experiments examined the role of visual feedback on the performance of a fine motor task, namely the rotary pursuit, in patients with Alzheimer's disease (AD) and healthy older adults. After extensive practice tracking a fully visible target, participants in Experiments 1 and 2 were tested under restricted vision (RV) conditions. In both experiments, the two groups showed a drop in performance when vision was restricted, with AD patients showing a significantly larger decline. Tracking improved significantly in normal controls, but not AD patients across the RV trials after the initial drop. When difficulty of the rotary pursuit task was manipulated in Experiment 3 without restricting vision, AD patients and normal controls showed identical patterns of performance. Consequently, it could be concluded that AD patients in the first two experiments were relying more heavily on visual information for accurate performance of the tracking task than their healthy peers.     

The relationship between Big-5 personality traits and cognitive ability in older adults – a review

It is well established that fundamental aspects of cognition such as memory and speed of processing tend to decline with age; however, there is substantial between-individual variability in levels of cognitive performance in older adulthood and in rates of change in cognitive abilities over time. Recent years have seen an increasing number of studies concerned with examining personality characteristics as possible predictors of some of this variability in cognitive aging. The purpose of this article is to review the literature, and identify patterns of findings regarding the relationships between personality (focusing on the Big-5) and cognitive ability across nonclinical populations of older adults. Possible mechanisms underlying associations of personality characteristics with cognition are reviewed, and assessed in the context of the current literature. Some relatively consistent relationships are identified, including positive associations between openness and cognitive ability, and associations of conscientiousness with slower rates of cognitive decline. However, the relationships between several personality traits and cognitive abilities in older adults remain unclear. We suggest some approaches to research design and analysis that may help increase our understanding of how personality differences may contribute to cognitive aging.     

A-Theory for B-Theorists

I attempt to characterize the A-theory of time in such a way as to avoid certain standard objections to it, like those derived from McTaggart's paradox. These objections often arise from conflation of the A-theory with other doctrines which are not entailed by it, but which happen to be held by individual A-theorists. In my view, the A-theory is most defensible when combined with a certain analysis of tense (which I call 'the counterfactual theory of tense'), and with realism about the past and future.     

Assessment Instruments Used by Addictions Counselors

The Association for Assessment in Counseling's Committee on Assessment and Training in Addictions Counseling conducted a survey of Master Addictions Counselors (MACs) certified by the National Board for Certified Counselors. The intent of the survey was to identify which standardized assessment instruments were most frequently used by MACs and perceived to be most important in their substance abuse practices. This article describes survey results and provides training and practice recommendations.