A daytime nap enhances visual working memory performance and alters event-related delay activity

Working memory (WM) is impaired following sleep loss and may be improved after a nap. The goal of the current study was to better understand sleep-related WM enhancement by: (1) employing a WM task that assesses the ability to hold and report visual representations as well as the fidelity of the reports on a fine scale, (2) investigating neurophysiological properties of sleep and WM capacity as potential predictors or moderators of sleep-related enhancement, and (3) exploring frontal and occipital event-related delay activity to index the neural processing of stimuli in WM. In a within-subjects design, 36 young adults (M_age = 20, 20 men, 16 women) completed a 300-trial, continuous-report task of visual WM following a 90-min nap opportunity and an equivalent period of wakefulness. Mixed-effect models were used to estimate the odds of successful WM reports and the fidelity of those reports. The odds of a successful report were approximately equal between nap and wake conditions for the start of the task, but by the end, the odds of success were 1.26 times greater in the nap condition. Successful WM reports were more accurate after a nap, independent of the time on task. Neither WM capacity nor any of the sleep variables measured were found to significantly moderate the nap effect on WM. Lastly, napping resulted in amplitude changes for frontal and occipital delay activity relative to the wake condition. The findings are discussed in relation to contemporary models of visual WM and the role of sleep in sustained attention.     

Epistemic Objects as Interactive Loci

Contemporary process metaphysics has achieved a number of important results, most significantly in accounting for emergence, a problem on which substance metaphysics has foundered since Plato. It also faces trenchant problems of its own, among them the related problems of boundaries and individuation. Historically, the quest for ontology may thus have been largely responsible for the persistence of substance metaphysics. But as Plato was well aware, an ontology of substantial things raises serious, perhaps insurmountable problems for any account of our epistemic access to such things. Physical things are subject to change, and as such, they are poor objects of knowledge—if knowledge is to be more reliable than mere opinion. There is a reading of Plato’s Theaetetus on which knowledge may be understood as a relation between an epistemic subject and a logos, where logoi are intrinsically dialectical, and where dialectic is a kind of intersubjective activity. Insofar as this epistemology may be attributed to Plato, the project of this paper is Platonic in spirit. It is also, in a sense, Kantian, in that it divorces ontology from the search for things-in-themselves, redirecting our attention from things to objects: epistemic objects. Such objects can be understood, as Maurice Merleau-Ponty proposed, as shared by multiple subjects by virtue of their participation in an intersubjective world, constituted by what Shaun Gallagher calls “participatory sense-making.” On an epistemology constructed in this way, the fact that both epistemic objects and their subject are mutable is no obstacle to knowledge. Far-from-equilibrium systems are forever mutable; at thermodynamic equilibrium, there would be neither subject, nor object. Epistemic objects, on this picture, are metastable loci of interactive potential.     

R��ckf?lligkeit nach nichtangeordneter nachtr?glicher Sicherungsverwahrung

Since 2001 under certain circumstances German courts have the right to order prisoner detention for preventive purposes retrospectively. As courts set limits to new facts after conviction more than 100 prisoners were released, although they were regarded as being very dangerous. The actual delinquency relapse of these persons was investigated in a study of the Ruhr University Bochum. The results are presented in this paper.     

Nuclear Brinkmanship: A Study in Non-Linguistic Communication

This article examines meaning making with nuclear bombs and military manoeuvres. The data is verbatim audio recordings from the White House during the Cuban Missile Crisis. The analysis uses concepts from impression management and dialogism. It is found that actions often speak louder than words and that even non-linguistic communication with nuclear weapons is often oriented to third-parties, in this case, world opinion. A novel process of ‘staging the other’ is identified, that is, when one side tries to create a situation which will force the other side to act in a way which will create a negative impression on world opinion. Staging the other is a subtle form of meaning making for it entails shaping how third parties will view a situation without those third parties being aware of the intentionality of the communication.     

Resource demands of object tracking and differential allocation of the resource

The attentional processes for tracking moving objects may be largely hemisphere-specific. Indeed, in our first two experiments the maximum object speed (speed limit) for tracking targets in one visual hemifield (left or right) was not significantly affected by a requirement to track additional targets in the other hemifield. When the additional targets instead occupied the same hemifield as the original targets, the speed limit was reduced. At slow target speeds, however, adding a second target to the same hemifield had little effect. At high target speeds, the cost of adding a same-hemifield second target was approximately as large as would occur if observers could only track one of the targets. This shows that performance with a fast-moving target is very sensitive to the amount of resource allocated. In a third experiment, we investigated whether the resources for tracking can be distributed unequally between two targets. The speed limit for a given target was higher if the second target was slow rather than fast, suggesting that more resource was allocated to the faster of the two targets. This finding was statistically significant only for targets presented in the same hemifield, consistent with the theory of independent resources in the two hemifields. Some limited evidence was also found for resource sharing across hemifields, suggesting that attentional tracking resources may not be entirely hemifield-specific. Together, these experiments indicate that the largely hemisphere-specific tracking resource can be differentially allocated to faster targets.     

How serious are expressions of protected values?

People think that some things that they value should be protected from trade-offs with other things. For example, people think that no economic gain is great enough to justify clear-cutting old-growth forest. The authors probed the stability of these protected values (PVs) in several ways. Subjects were asked to think of counterexamples, and this had some effect on PVs. Subjects were then asked how they would resolve conflicts between 2 PVs. Resolutions did not differ from those between other values, but subjects tended to feel that conflicts between PVs did not occur in reality. Despite people's claims that PVs are unchanged by variation in quantity, expression of PVs was reduced when the magnitude or probability of the violation of a PV was smaller. In summary, PVs appear to be labile and amenable to challenge. Despite earlier concerns, apparent PVs may not always preclude the use of valuation measures in cost-effectiveness analysis or negotiated agreement on controversial issues.     

The development of implicit attitudes. Evidence of race evaluations from ages 6 and 10 and adulthood

To understand the origin and development of implicit attitudes, we measured race attitudes in White American 6-year-olds, 10-year-olds, and adults by first developing a child-oriented version of the Implicit Association Test (Child IAT). Remarkably, implicit pro-White/anti-Black bias was evident even in the youngest group, with self-reported attitudes revealing bias in the same direction. In 10-year-olds and adults, the same magnitude of implicit race bias was observed, although self-reported race attitudes became substantially less biased in older children and vanished entirely in adults, who self-reported equally favorable attitudes toward Whites and Blacks. These data are the first to show an asymmetry in the development of implicit and explicit race attitudes, with explicit attitudes becoming more egalitarian and implicit attitudes remaining stable and favoring the in-group across development. We offer a tentative suggestion that mean levels of implicit and explicit attitudes diverge around age 10.     

The relation of neediness and Axis II pathology

Neediness, as a maladaptive form of interpersonal dependency, has been implicated in a range of psychopathology, most commonly mood and personality disorders. In light of the literature's sparse and inconsistent findings, Bornstein, Hilsenroth, Padawer, and Fowler (2000) have called for a systematic evaluation of dependency's role across the spectrum of Axis II disorders. The current study of individuals without current or past Axis I diagnoses found that Neediness was significantly related to dimensions of dependent, borderline, and histrionic personality disorders. Implications for the assessment of interpersonal dependency and issues in need of further clarification are highlighted.     

Repetition and the brain: neural models of stimulus-specific effects

One of the most robust experience-related cortical dynamics is reduced neural activity when stimuli are repeated. This reduction has been linked to performance improvements due to repetition and also used to probe functional characteristics of neural populations. However, the underlying neural mechanisms are as yet unknown. Here, we consider three models that have been proposed to account for repetition-related reductions in neural activity, and evaluate them in terms of their ability to account for the main properties of this phenomenon as measured with single-cell recordings and neuroimaging techniques. We also discuss future directions for distinguishing between these models, which will be important for understanding the neural consequences of repetition and for interpreting repetition-related effects in neuroimaging data.