Conditioning against the Grain

This paper discusses counterexamples to the thesis that the probabilities of conditionals are conditional probabilities. It is argued that the discrepancy is systematic and predictable, and that conditional probabilities are crucially involved in the apparently deviant interpretations. Furthermore, the examples suggest that such conditionals have a less prominent reading on which their probability is in fact the conditional probability, and that the two readings are related by a simple step of abductive inference. Central to the proposal is a distinction between causal and purely stochastic dependence between variables.     

Kontroverse zu Beschwerdenvalidierungsverfahren bei der Begutachtung psychischer St?rungen

The value of symptom validity tests in a forensic context is currently the subject of a controversial debate in Germany. The discussion primarily focuses on neuropsychological symptom validity tests, however, tests specific for mental disorders are neglected. Unfortunately, no assessment tools for symptom validation of mental disorders of German origin are available and adaptations of available English state of the art instruments have not yet been tested. Further research of assessment development and qualitative analysis of the decision-making process in medicolegal evaluation is needed in German speaking countries.     

Does symptomatic schizophrenia exist?

The question if there are "symptomatic schizophrenias" has been discussed since the 20s. Schizophrenic psychoses caused be definable and well known brain diseases are presented. All schizophrenic symptoms and syndromes, the first rank symptoms (K. Schneider) too, occur in somatically founded psychoses. The group of paroxysmal transition syndromes in the sense of aura prolongata (continua) and the episodic schizophrenic psychoses in psychomotor epilepsy may be a model for the schizophrenia research. Vital threatening, so-called pernicious catatonic schizophrenias are found on the basis of infectious brain diseases, sometimes only diagnosed in autopsy. Beside acute and reversible symptomatic schizophrenic psychoses there are, even if rarely, recurrent and chronic courses of symptomatic schizophrenias. That certain conditions for the developing of symptomatic schizophrenias are rarely realised, could be an explanation for their rarity. Some findings indicate that the limbic system is significant for symptomatic (and idiopathic) schizophrenic psychoses and the pre- and postpsychotic basic stages determined by dynamic and cognitive basic symptoms, which are phenomenologically very similar to aura symptoms released by stereoelectroencephalographic depth recordings (Wieser). The characteristic features of marked fluctuation, discontinuity and insteadiness of the cognitive thought, perception, psychomotor and cenesthetic phenomena do not speak against an organic brain disorder provided that the traditional process hypothesis is abandoned in favor of a neurobiochemic disorder, fluctuating on its part depending on endogenous as well as psychic-reactive factors.     

Neurophysiology and neuroanatomy of reflexive and voluntary saccades in non-human primates

A multitude of cognitive functions can easily be tested by a number of relatively simple saccadic eye movement tasks. This approach has been employed extensively with patient populations to investigate the functional deficits associated with psychiatric disorders. Neurophysiological studies in non-human primates performing the same tasks have begun to provide us with insights into the neural mechanisms underlying many cognitive functions. Here, we review studies that have investigated single neuron activity in the superior colliculus (see glossary), frontal eye field, supplementary eye field, dorsolateral prefrontal cortex, anterior cingulate (see glossary) cortex and lateral intraparietal area associated with the performance of visually guided saccades, anti-saccades and memory-guided saccades in awake behaving monkeys.     

Visual categorization of natural stimuli by domestic dogs

One of the fundamental issues in the study of animal cognition concerns categorization. Although domestic dogs (Canis familiaris) are on the brink to become one of the model animals in animal psychology, their categorization abilities are unknown. This is probably largely due to the absence of an adequate method for testing dogs’ ability to discriminate between large sets of pictures in the absence of human cueing. Here we present a computer-automated touch-screen testing procedure, which enabled us to test visual discrimination in dogs while social cueing was ruled out. Using a simultaneous discrimination procedure, we first trained dogs (N = 4) to differentiate between a set of dog pictures (N = 40) and an equally large set of landscape pictures. All subjects learned to discriminate between the two sets and showed successful transfer to novel pictures. Interestingly, presentation of pictures providing contradictive information (novel dog pictures mounted on familiar landscape pictures) did not disrupt performance, which suggests that the dogs made use of a category-based response rule with classification being coupled to category-relevant features (of the dog) rather than to item-specific features (of the background). We conclude that dogs are able to classify photographs of natural stimuli by means of a perceptual response rule using a newly established touch-screen procedure. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Attention capture by faces

We report three experiments that investigate whether faces are capable of capturing attention when in competition with other non-face objects. In Experiment 1a participants took longer to decide that an array of objects contained a butterfly target when a face appeared as one of the distracting items than when the face did not appear in the array. This irrelevant face effect was eliminated when the items in the arrays were inverted in Experiment 1b ruling out an explanation based on some low-level image-based properties of the faces. Experiment 2 replicated and extended the results of Experiment 1a. Irrelevant faces once again interfered with search for butterflies but, when the roles of faces and butterflies were reversed, irrelevant butterflies no longer interfered with search for faces. This suggests that the irrelevant face effect is unlikely to have been caused by the relative novelty of the faces or arises because butterflies and faces were the only animate items in the arrays. We conclude that these experiments offer evidence of a stimulus-driven capture of attention by faces.     

Forward inference in risky choice: Mapping gaze and decision processes

The study of cognitive processes is built on a close mapping between three components: overt gaze behavior, overt choice, and covert processes. To validate this overt–covert mapping in the domain of decision‐making, we collected eye‐movement data during decisions between risky gamble problems. Applying a forward inference paradigm, participants were instructed to use specific decision strategies to solve those gamble problems (maximizing expected values or applying different choice heuristics) during which gaze behavior was recorded. We revealed differences between overt behavior, as indicated by eye movements, and covert decision processes, instructed by the experimenter. However, our results show that the overt–covert mapping is for some eye‐movement measures not as close as expected by current decision theory, and hence question reverse inference as being prone to fallacies due to a violation of its prerequisite, that is, a close overt–covert mapping. We propose a framework to rehabilitate reverse inference.     

Applications Of Elementary Submodels In General Topology

Elementary submodels of some initial segment of the set-theoretic universe are useful in order to prove certain theorems in general topology as well as in algebra. As an illustration we give proofs of two theorems due to Arkhangelskii concerning cardinal invariants of compact spaces.