Color filling-in under steady fixation: behavioral demonstration in monkeys and humans

Color filling-in is a phenomenon in which the color of an object appears to be filled-in by the color of the surrounding field. We have studied the question of whether monkeys perceive color filling-in with near-foveal stimuli under steady fixation. Two monkeys were trained to fixate steadily and to attend to a disk, surrounded by an annulus of the complementary color, in parafoveal vision. Using displays in which the color of the disk was gradually changed to that of the annulus, we trained the animals to signal when they perceived a uniform color field. During the experiment, we introduced a small percentage of trials in which the disk color remained constant, and looked for 'filling-in' responses in these trials. Three human subjects were also tested for comparison. All subjects produced 'filling-in' responses with frequencies that were significantly higher for static disks with blurred borders than for moving disks or disks with sharp borders. This indicates that the monkeys' responses reflected perceptual filling-in, rather than random behavior. The time course of filling-in was similar in monkeys and humans. For the blurred static disks, responses occurred first after 3-4 s of fixation, reaching a probability of 0.2-0.8 by the end of 6 s, depending on the subject.     

Vienna Indeterminism: Mach,Boltzmann, Exner

The present paper studies a specific way of addressing the question whether the laws involving the basic constituents of nature are statistical. While most German physicists, above all Planck, treated the issues of determinism and causality within a Kantian framework, the tradition which I call Vienna Indeterminism began from Mach’s reinterpretation of causality as functional dependence. This severed the bond between causality and realism because one could no longer avail oneself of a priori categories as a criterion for empirical reality. Hence, an independent reality criterion had to be sought, a problem which all three physicists to be studied solved in different ways that were mainly conditioned by their different concepts of probability. In order to prevent a dissipation of intuited facts, Mach had to resort to a principle of unique determination as his reality criterion, especially when discussing the Principle of Least Action. Giving theories more independence, Boltzmann understood atomism as property reduction to precisely defined theoretical entities and their interactions. While this served as a relative reality criterion, he also advocated a constructivist one because atomism was already implied by our finitary reasoning power. Finally, Exner contemplated the idea that all apparently deterministic laws are only a macroscopic limit of an irreducible indeterminism, because by adopting the frequency interpretation, observable collectives could be considered as the real basic entities. This revised version was published online in June 2006 with corrections to the Cover Date.     

Every Finitely Reducible Logic has the Finite Model Property with Respect to the Class of ♦-Formulae

In this paper a unified framework for dealing with a broad family of propositional multimodal logics is developed. The key tools for presentation of the logics are the notions of closure relation operation and monotonous relation operation. The two classes of logics: FiRe-logics (finitely reducible logics) and LaFiRe-logics (FiRe-logics with local agreement of accessibility relations) are introduced within the proposed framework. Further classes of logics can be handled indirectly by means of suitable translations. It is shown that the logics from these classes have the finite model property with respect to the class of -formulae, i.e. each -formula has a -model iff it has a finite -model. Roughly speaking, a -formula is logically equivalent to a formula in negative normal form without occurrences of modal operators with necessity force. In the proof we introduce a substantial modification of Claudio Cerrato's filtration technique that has been originally designed for graded modal logics. The main core of the proof consists in building adequate restrictions of models while preserving the semantics of the operators used to build terms indexing the modal operators.     

Interkulturelle Trainings für die psychosoziale Versorgung

The psychosocial care of patients with a migration background is often related to higher access barriers. Also for professionals in mental health care service the treatment of patients with a migration background often represents a challenge. One way to overcome such barriers is to train care givers in order to enhance cross-cultural competence. In addition to knowledge transfer such training focuses on the process of self-reflection and examination of ones own, as well as the unknown cultural orientation system. Sufficient effectiveness of cross-cultural training has been proven on an international level. However, evaluation studies are lacking in the German speaking region. Additionally, guidelines or quality criteria for providers of training for psychosocial care professionals are lacking. Validated psychometric instruments which assess cross-cultural competence in individuals hardly exist. The present article gives an overview of concepts of cross-cultural competence and the effectiveness of such training. Also an outlook is given on the future prospects of development in the field.     

The effect of applicant–employee fit and temporal construal on employer attraction and pursuit intentions

Although applicant–employee fit has emerged as an important topic in recruitment research, little is known about how job seekers’ perceived similarity with the employees working for an organization affects employer attraction. In this research, we introduce temporal construal as a crucial moderating variable and study how the temporal decision context affects the weighting of applicant–employee fit. In particular, we argue that applicant–employee fit is construed in abstract, high‐level terms, and exerts a stronger influence when prospective applicants hold a distant time perspective. In contrast, instrumental attributes such as pay level represent low‐level construals and gain greater relevance when prospective applicants hold a near time perspective. Two experiments involving a student sample and a sample of unemployed job seekers supported these predictions.     

The synergy of working memory and inhibitory control: behavioral, pharmacological and neural functional evidences

Concomitant deficits in working memory and behavioral inhibition in several psychiatric disorders like attention-deficit/hyperactivity disorder, addiction or mania, suggest that common brain mechanisms may underlie their etiologies. Based on the theoretical assumption that a continuum exists between health and mental disorders, we explored the relationship between working memory and inhibition in healthy individuals, through spontaneous inter individual differences in behavior, and tested the hypothesis of a functional link through the fronto-striatal dopaminergic system. Rats were classified into three groups, showing good, intermediate and poor working memory and were compared for their inhibitory abilities. These two functions were simultaneously modulated by a dose-effect of d-amphetamine and in situ hybridization was used to quantify dopaminergic receptor (RD1) mRNAs in prefrontal cortex and striatal areas. A functional relationship between working memory and inhibition abilities was revealed. Both functions were similarly modulated by d-amphetamine according to an inverted-U shaped relationship and depending on initial individual performances. D-amphetamine selectively improved working memory and inhibition of poor and intermediate performers at low doses whereas it impaired both processes in good performers at a higher dose. D1 receptors were less expressed in prelimbic, infralimbic and anterior cingulate cortices of good compared to intermediate and poor performers, whereas no difference was observed between groups in striatal areas. The synergy of working memory and inhibitory abilities, observed in both healthy and psychiatric populations, may originate from endogenous variability in dopaminergic prefrontal cortex activity. Such findings confirm the validity of a dimensional approach, based on the concept of continuity between health and mental disorders for identifying endophenotypes of mental disorders.     

Associative memory or algorithmic search: a comparative study on learning strategies of bats and shrews

Two common strategies for successful foraging are learning to associate specific sensory cues with patches of prey ("associative learning") and using set decision-making rules to systematically scan for prey ("algorithmic search"). We investigated whether an animal's life history affects which of these two foraging strategies it is likely to use. Natterer's bats (Myotis nattereri) have slow life-history traits and we predicted they would be more likely to use associative learning. Common shrews (Sorex araneus) have fast life-history traits and we predicted that they would rely more heavily on routine-based search. Apart from their marked differences in life-history traits, these two mammals are similar in body size, brain weight, habitat, and diet. We assessed foraging strategy, associative learning ability, and retention time with a four-arm maze; one arm contained a food reward and was marked with four sensory stimuli. Bats and shrews differed significantly in their foraging strategies. Most bats learned to associate the sensory stimuli with the reward and remembered this association over time. Most shrews searched the maze using consistent decision-making rules, but did not learn or remember the association. We discuss these results in terms of life-history traits and other key differences between these species. Our results suggest a link between an animal's life-history strategy and its use of associative learning.