The concavity effect is a compound of local and global effects

Using a change detection paradigm, Barenholtz, Cohen, Feldman, and Singh (2003) found that changes in concave regions of a contour are more easily detected than changes in convex regions. In a series of three experiments, we investigated this concavity effect using the same paradigm. We observed the effect in wire-like stimuli as well as in silhouettes (Experiment 1) and in complex, smoothed images as opposed to angular polygons (Experiment 2). We also observed a systematic effect of the magnitude of the change (Experiment 1). Furthermore, we find that the effect cannot be attributed to either local or global processing effects, but rather to a combination of both "mere" concaveness and an effect due to changes in the perceived part structure of the stimulus object (Experiment 3). For our data analysis, we used a nonparametric bootstrap method, which greatly increases sensitivity (compared to more traditional analyses like ANOVA).     

Hypothetical Retrospection

Moral theory has mostly focused on idealized situations in which the morally relevant properties of human actions can be known beforehand. Here, a framework is proposed that is intended to sharpen moral intuitions and improve moral argumentation in problems involving risk and uncertainty. Guidelines are proposed for a systematic search of suitable future viewpoints for hypothetical retrospection. In hypothetical retrospection, a decision is evaluated under the assumption that one of the branches of possible future developments has materialized. This evaluation is based on the deliberator’s present values, and each decision is judged in relation to the information available when it was taken. The basic decision rule is to choose an alternative that comes out as morally acceptable (permissible) from all hypothetical retrospections.

Die Psychotherapieausbildung aus Sicht der Lehrkräfte

Background

A survey was carried out to ask the trainers and supervisors about their appraisal of the quality of the psychotherapy training and about ways to improve it 10 years after the inception of the “German psychotherapy law”.

Methods

Training institutes provided e-mail addresses and other contact information from over 5,000 trainers. The questioning was carried out mainly by on-line questionnaires and 2,196 data sets were used for analysis.

Results

Trainers showed overall satisfaction with the components of psychotherapy training and the skills of the training candidates. More knowledge transfer in the fields of therapy techniques and case studies and more cooperation with other professional groups were suggested. Trainers acknowledged redundancies between professional training and university studies and observed a heterogeneity of trainees, however, these were mostly considered helpful. Only half of the trainers were subject to evaluation of their work.

Conclusions

The quality of psychotherapy training could be improved by stronger emphasis on practical knowledge. Structural changes should be made to take the problem of redundancies and heterogeneities into account. Regular and continuous evaluation of the training should become an integral part of professional training and the results should have consequences.     

Replacement—A Sheffer Stroke for Belief Change

By replacement is meant an operation that replaces one sentence by another in a belief set. Replacement can be used as a kind of Sheffer stroke for belief change, since contraction, revision, and expansion can all be defined in terms of it. Replacement can also be defined either in terms of contraction or in terms of revision. Close connections are shown to hold between axioms for replacement and axioms for contraction and revision. Partial meet replacement is axiomatically characterized. It is shown that this operation can have outcomes that are not obtainable through either partial meet contraction or partial meet revision.     

Farewell to Objectivity: A Critique of Brandom

I argue that Brandom's account of inconsistency in terms of the pragmatic notion of incompatibility, as originally set out in his Making It Explicit (1994) and defended in Articulating Reasons (2000), has the absurd consequence that all true claims are warranted. This is in obvious conflict with our ordinary conception of truth as objective, which is what Brandom intends to capture. My proof proceeds from two principles, extracted from Making It Explicit , that govern the notions of commitment and entitlement in terms of which the notion of incompatibility is being defined. If either of these principles is rejected, it will no longer be clear what the content of Brandom's thesis is.     

Knowing The World By Knowing One's Mind

This paper addresses the question whetherintrospection plus externalism about mental contentwarrant an a priori refutation of external-worldskepticism and ontological solipsism. The suggestionis that if thought content is partly determined byaffairs in the environment and if we can havenon-empirical knowledge of our current thoughtcontents, we can, just by reflection, know about theworld around us – we can know that our environment ispopulated with content-determining entities. Afterexamining this type of transcendental argument anddiscussing various objections found in the literature,I argue that the notion of privileged self-knowledgeunderlying this argument presupposes that we canlearn, via introspection, that our so-called thoughtsare propositional attitudes rather than contentlessstates. If, however, externalism is correct andthought content consists in the systematic dependencyof internal states on relational properties, we cannotknow non-empirically whether or not we havepropositional attitudes. Self-knowledge (apropositional attitude) is consistent with us lackingthe ability to rule out, via introspection, thepossibility that we don't have any propositionalattitudes. Self-knowledge provides us with knowledgeof what is in our minds, but not that we haveminds. Hence, the combination of externalism with thedoctrine of privileged self-knowledge does not allowfor an a priori refutation of skepticism and istherefore unproblematic.     

Phosphodiesterase type 5 (PDE5) inhibition improves object recognition memory: indications for central and peripheral mechanisms

A promising target for memory improvement is phosphodiesterase type 5 (PDE5), which selectively hydrolyzes cyclic guanosine monophosphate (cGMP). In rodents, PDE5 inhibitors (PDE5-Is) have been shown to improve memory performance in many behavioral paradigms. However, it is questioned whether the positive effects in animal studies result from PDE5 inhibition in the central nervous system or the periphery. Therefore, we studied the effects of PDE5 inhibition on memory and determined whether compound penetration of the blood-brain barrier (BBB) is required for this activity. Two selective PDE5-Is, vardenafil and UK-343,664, were tested in the object recognition task (ORT) in both a MK-801- and scopolamine-induced memory deficit model, and a time-delay model without pharmacological intervention. Compounds were dosed 30 min before the learning trial of the task. To determine if the PDE5-Is crossed the BBB, their concentrations were determined in plasma and brain tissue collected 30 min after oral administration. Vardenafil improved object recognition memory in all three variants of the ORT. UK-343,664 was ineffective at either preventing MK-801-induced memory disruption or time-dependent memory decay. However, UK-343,664 attenuated the memory impairment of scopolamine. Vardenafil crossed the BBB whereas UK-343,664 did not. Further, co-administration of UK-343,664 and scopolamine did not alter the brain partitioning of either molecule. This suggests that the positive effect of UK-343,664 on scopolamine-induced memory decay might arise from peripheral PDE5 inhibition. The results herein suggest that there may be multiple mechanisms that mediate the efficacy of PDE5 inhibition to improve memory performance in tasks such as the ORT and that these involve PDE5 located both within and outside of the brain. To further elucidate the underlying mechanisms, the cellular and subcellular localization of PDE5 needs to be determined.