Evidence for a fixed capacity limit in attending multiple locations

A classic question concerns whether humans can attend multiple locations or objects at once. Although it is generally agreed that the answer to this question is “yes,” the limits on this ability are subject to extensive debate. According to one view, attentional resources can be flexibly allocated to a variable number of locations, with an inverse relationship between the number of selected locations and the quality of information processing at each location. Alternatively, these resources might be quantized in a “discrete” fashion that enables concurrent access to a small number of locations. Here, we report a series of experiments comparing these alternatives. In each experiment, we cued participants to attend a variable number of spatial locations and asked them to report the orientation of a single, briefly presented target. In all experiments, participants’ orientation report errors were well-described by a model that assumes a fixed upper limit in the number of locations that can be attended. Conversely, report errors were poorly described by a flexible-resource model that assumes no fixed limit on the number of locations that can be attended. Critically, we showed that these discrete limits were predicted by cue-evoked neural activity elicited before the onset of the target array, suggesting that performance was limited by selection processes that began prior to subsequent encoding and memory storage. Together, these findings constitute novel evidence supporting the hypothesis that human observers can attend only a small number of discrete locations at an instant.     

Spanning our differences: moral psychology,physician beliefs,and the practice of medicine

Moral pluralism is the norm in contemporary society. Even the best philosophical arguments rarely persuade moral opponents who differ at a foundational level. This has been vividly illustrated in contemporary debates in bioethics surrounding contentious issues such as abortion and euthanasia. It is readily apparent that bioethics discourse lacks an empirical explanation for the broad differences about various topics in bioethics and health policy. In recent years, social and cognitive psychology has generated novel approaches for defining basic differences in moral intuitions generally. We propose that if empirical research using social intuitionist theory explains why people disagree with one another over moral issues, then the results of such research might help people debate their moral differences in a more constructive and civil manner. We illustrate the utility of social intuitionism with data from a national physician survey.     

Within-hemifield posture changes affect tactile–visual exogenous spatial cueing without spatial precision,especially in the dark

We investigated the effects of seen and unseen within-hemifield posture changes on crossmodal visual–tactile links in covert spatial attention. In all experiments, a spatially nonpredictive tactile cue was presented to the left or the right hand, with the two hands placed symmetrically across the midline. Shortly after a tactile cue, a visual target appeared at one of two eccentricities within either of the hemifields. For half of the trial blocks, the hands were aligned with the inner visual target locations, and for the remainder, the hands were aligned with the outer target locations. In Experiments 1 and 2, the inner and outer eccentricities were 17.5º and 52.5º, respectively. In Experiment 1, the arms were completely covered, and visual up–down judgments were better when on the same side as the preceding tactile cue. Cueing effects were not significantly affected by hand or target alignment. In Experiment 2, the arms were in view, and now some target responses were affected by cue alignment: Cueing for outer targets was only significant when the hands were aligned with them. In Experiment 3, we tested whether any unseen posture changes could alter the cueing effects, by widely separating the inner and outer target eccentricities (now 10º and 86º). In this case, hand alignment did affect some of the cueing effects: Cueing for outer targets was now only significant when the hands were in the outer position. Although these results confirm that proprioception can, in some cases, influence tactile–visual links in exogenous spatial attention, they also show that spatial precision is severely limited, especially when posture is unseen.     

The Relationship of Nondirectiveness to Genetic Counseling: Report of a Workshop at the 2003 NSGC Annual Education Conference

Nondirectiveness has been a guiding principle for genetic counseling since the founding of the profession. However, its efficacy and appropriateness in this role have been frequently questioned. A workshop at the 2003 Annual Education Conference of the National Society of Genetic Counselors provided audience participation in a discussion of these issues. Participants presented arguments for and against nondirectiveness as a central ethos. They described complex personal transitions in adapting what they had learned about nondirectiveness during training to the realities of the workplace. There was support for flexible approaches to genetic counseling, with varying adherence to nondirectiveness, based on client and family needs and values, clinical circumstances, and desired counseling outcomes. The discussion supports the use of clinical experience, outcomes research, and the experience of other professions to move beyond nondirectiveness and more accurately identify the theoretical bases that underlie genetic counseling in the variety of circumstances in which it is currently practiced.     

Actuarial models for assessing prison violence risk: revisions and extensions of the Risk Assessment Scale for Prison (RASP)

An investigation and extension of the Risk Assessment Scale for Prison (RASP-Potosi), an actuarially derived scale for the assessment of prison violence, was undertaken through a retrospective review of the disciplinary records of the first 12 months of confinement of a cohort of inmates entering the Florida Department of Corrections in 2002 and remaining throughout 2003 (N=14,088). A near replication of the RASP-Potosi and additional analyses based on other weighted logistic regression models were performed on an inmate subsample for whom all information categories were available (n=13,341). Younger age and shorter sentences were associated with increased violent misconduct. Older age, drug conviction, and higher educational attainment were associated with reduced violent misconduct. Regardless of whether the original RASP-Potosi or its progeny were utilized, or the custody level of the inmate sample, the models were modestly successful in predicting prison violence, with the area under the curve (AUC) ranging from .645 to .707.     

The neurobiology of substance and behavioral addictions

Behavioral addictions, such as pathological gambling, kleptomania, pyromania, compulsive buying, and compulsive sexual behavior, represent significant public health concerns and are associated with high rates of psychiatric comorbidity and mortality. Although research into the biology of these behaviors is still in the early stages, recent advances in the understanding of motivation, reward, and addiction have provided insight into the possible pathophysiology of these disorders. Biochemical, functional neuroimaging, genetic studies, and treatment research have suggested a strong neurobiological link between behavioral addictions and substance use disorders. Given the substantial co-occurrence of these groups of disorders, improved understanding of their relationship has important implications not only for further understanding the neurobiology of both categories of disorders but also for improving prevention and treatment strategies.