A memory-based model of Hick's law

We propose and evaluate a memory-based model of Hick’s law, the approximately linear increase in choice reaction time with the logarithm of set size (the number of stimulus–response alternatives). According to the model, Hick’s law reflects a combination of associative interference during retrieval from declarative memory and occasional savings for stimulus–response repetitions due to non-retrieval. Fits to existing data sets show that the model accounts for the basic set-size effect, changes in the set-size effect with practice, and stimulus–response-repetition effects that challenge the information-theoretic view of Hick’s law. We derive the model’s prediction of an interaction between set size, stimulus fan (the number of responses associated with a particular stimulus), and stimulus–response transition, which is subsequently tested and confirmed in two experiments. Collectively, the results support the core structure of the model and its explanation of Hick’s law in terms of basic memory effects.     

Evidenzbasierte Psychotherapie der Depression

Depressive disorders are among the most frequent reasons for utilizing the health care system. Despite the availability of efficacious treatments and further advances throughout the last years, there is still a need for improving diagnostic and therapeutic procedures. A promising approach is the implementation of evidence- and consensus-based guidelines. The German “Nationale VersorgungsLeitlinie Unipolare Depression” are evidence- and consensus-based clinical practise guidelines for patients with unipolar depression. All relevant stakeholders have been involved in its development and have passed the final version at the end of 2009 to foster compliance throughout. The available evidence allows the derivation of differentiated treatment recommendations, also with regard to concomitant antidepressant medication or as alternative treatment options. In acute therapy watchful waiting over 14 days is recommended for mild depression and psychotherapy after persistence of symptoms. In cases of moderate depression, psychotherapy and pharmacotherapy are equally recommended, in cases of severe depression a combination of both is recommended.     

Berufliche Leistungsfähigkeit

In different fields of law the assessment of capability of performance is important and often poses a particular challenge for medical or psychological experts. The present article introduces a model for the assessment of capability of performance developed on the background of a multicenter and interdisciplinary research project. This approach of assessment assumes that the performance capability of a person with psychiatric or psychosomatic disorders does not arise from symptomatology alone; instead, it is also a consequence of interactions between coping processes of the individual and environmental factors. The presented model of the assessment of performance capability is mainly oriented to the “International Classification of Functioning” (ICF; WHO) whose central diagnostic categories are, in addition to the disorder and the somatic and psychiatric functions, the levels of activity and participation. The different assessing levels are operationalized in the assessment model. In this article the various diagnostic levels and their interactions and the criteria which have been formulated are described. The process of decision-making is explored as well. This assessment model aims to make a more reliable, valid and transparent process of expert decision-making in order to increase the objectivity and justice of the assessment procedure.     

Essentialist theory of ‘hybrids’: From animal kinds to ethnic categories and race

This article presents a theory of the perception of hybrids, resulting from cross‐breeding natural animals that pertain to different species and of children parented by couples with a mixed ethnic or racial background. The theory states that natural living beings, including humans, are perceived as possessing a deeply ingrained characteristic that is called ‘essence’ or ‘blood’ or ‘genes’ in everyday discourse and that uniquely determines their category membership. If, by whatever means, the genes or essences of two animals of different species are combined in a hybrid, the two incompatible essences collapse, leaving the hybrid in a state of non‐identity and non‐belonging. People despise this state and reject the hybrid (Study 1). This devaluation effect holds with cross‐kind hybrids and with hybrids that arise from genetically combining animals from incompatible habitats across three cultures: Austria, India and Japan (Study 2). In the social world, groups and ethnic or racial categories frequently are essentialized in an analogue way. When people with an essentialist mindset judge ethnically or racially mixed offspring, they perceive a collapse of ethnic or racial essence and, consequently, denigrate these children, as compared to children from ‘pure’ in‐group or out‐group parents (Study 3). The findings are discussed in terms of the widespread ‘yuck factor’ against genetically modified animals, in terms of the cultural concepts of monstrosity and of racism and prejudice.     

Learning of magnetic compass directions in pigeons

A proof of magnetic compass learning by pigeons under laboratory conditions has been attempted for decades, but all experiments have failed so far. The aim of the present study was to test whether pigeons can learn magnetic compass directions in an operant chamber if magnetic cues are presented as true spatial cues. Experimental sessions were carried out in the local geomagnetic field and in magnetic fields with matched total intensity and inclination, but different directions generated with Helmholtz-coils. Birds demonstrated successful learning with a performance level comparable to that in learning studies with magnetic anomalies. In addition, we compared the data from magnetic learning in the laboratory with performance from homing experiments in the field. The birds that were more successful in the learning experiment had vanishing bearings farther away from the home direction than the group mean at unfamiliar, but not at familiar sites. This might suggest that better learners explore unknown locations in a different way. Our findings represent the first evidence for operant magnetic compass learning in pigeons and also provide a link between behavioural data from the field and the laboratory.     

Das Leugnen der Tat bei der Entscheidung über die Aussetzung der Reststrafe

The article is about the question whether or not a convicted person can be released on probation even though they are denying their offence. According to German Criminal Law, release on probation must be considered (by a special chamber of the court, “Chamber of Execution”; same question for any kind of Parole Board in other countries) in every case as soon as two thirds of the sentence are served, regardless the convicted person does or does not confess their offence. Using a case example, the article will show as to how the convict’s denial becomes a meaningful fact in the decision-making process. Besides referring to certain conclusions about criminal prognosis following from denying – which of course is a main issue with the decision about release, often valued by the help of expert testimony –, the focus will be set on the judicial framework around this question: Does the law give provisions on how to deal with denial, and how does the principle “nemo tenetur” (nobody has to charge themselves, harm their defence, nor give evidence against themselves) impact the considerations?     

Has someone moved my plate? The immediate and persistent effects of object location changes on gaze allocation during natural scene viewing

In this study, we investigated the immediate and persisting effects of object location changes on gaze control during scene viewing. Participants repeatedly inspected a randomized set of naturalistic scenes for later questioning. On the seventh presentation, an object was shown at a new location, whereas the change was reversed for all subsequent presentations of the scene. We tested whether deviations from stored scene representations would modify eye movements to the changed regions and whether these effects would persist. We found that changed objects were looked at longer and more often, regardless of change reportability. These effects were most pronounced immediately after the change occurred and quickly leveled off once a scene remained unchanged. However, participants continued to perform short validation checks to changed scene regions, which implies a persistent modulation of eye movement control beyond the occurrence of object location changes.     

The information content of panoramic images II: view-based navigation in nonrectangular experimental arenas

Two recent studies testing navigation of rats in swimming pools have posed problems for any account of the use of purely geometric properties of space in navigation (M. Graham, M. A. Good, A. McGregor, & J. M. Pearce, 2006; J. M. Pearce, M. A. Good, P. M. Jones, & A. McGregor, 2004). The authors simulated 1 experiment from each study in a virtual reality environment to test whether experimental results could be explained by view-based navigation. The authors recorded a reference image at the target location and then determined global panoramic image differences between this image and images taken at regularly spaced locations throughout the arena. A formal model, in which an agent attempts to minimize image differences between the reference image and current views, generated trajectories that could be compared with the search performance of rats. For both experiments, this model mimics many aspects of rat behavior. View-based navigation provides a sufficient and parsimonious explanation for a range of navigational behaviors of rats under these experimental conditions.     

Was ist seit BGHSt 45, 164 geschehen? Ein Überblick über die neuere Rechtsprechung des Bundesgerichtshofs zur Beurteilung der Glaubhaftigkeit von Zeugenaussagen

Zusammenfassung  Der 1. Strafsenat des Bundesgerichtshofs hat in seinem Urteil vom 30. Juli 1999 (BGHSt 45, 164) die wissenschaftlichen Anforderungen beschrieben, die an eine aussagepsychologische Begutachtung (Glaubhaftigkeitsgutachten) zu stellen sind, und die Richter verpflichtet, zukünftig darauf zu achten, dass diese Mindeststandards bei der Erstattung von Gutachten eingehalten werden. Ausgehend von dieser Entscheidung stellt der Beitrag die seitherige Entwicklung der Rechtsprechung zur Glaubhaftigkeitsbeurteilung von Zeugenaussagen dar. Er geht dabei über die an das Gutachten zu stellenden Anforderungen hinaus und befasst sich auch damit, wann ein solches Gutachten erforderlich, von wem es zu erstatten und in welcher Weise es vom Richter in den Entscheidungsgründen darzustellen ist. Zudem schildert er, welchen Einfluss die Anerkennung der hypothesengeleiteten, kriterienorientierten Aussageanalyse auf die Beweiswürdigung durch den Tatrichter und deren überprüfung durch das Revisionsgericht hat.