Contingency awareness in a symptom learning paradigm: necessary but not sufficient?

In previous studies, we found that bodily symptoms can be learned in a differential conditioning paradigm, using odors as conditioned stimuli (CSs) and CO2-enriched air as unconditioned stimulus (US). However, this only occurred when the odor CS had a negative valence (a selective conditioning effect), and tended to be more pronounced in persons scoring high for Negative Affectivity (NA). This paper considers the necessity and/or sufficiency of awareness of the CS-US contingency in three studies using this paradigm. The relation between contingency awareness and the selective conditioning effect, and between contingency awareness and NA was also considered. Both self reported symptoms and respiratory physiology served as dependent variables. A learning effect on symptoms was found only for participants aware of the CS-US contingency, but not all participants reporting contingency awareness showed a learning effect. No conditioning effects appeared on the physiological measures. Also contingency awareness did not account for the selective conditioning effect, and did not interact with NA. Overall, the necessity but insufficiency hypotheses can only be withhold for group data and not for individual data.     

Brain Networks in Schizophrenia

Schizophrenia—a severe psychiatric condition characterized by hallucinations, delusions, loss of initiative and cognitive function—is hypothesized to result from abnormal anatomical neural connectivity and a consequent decoupling of the brain’s integrative thought processes. The rise of in vivo neuroimaging techniques has refueled the formulation of dysconnectivity hypotheses, linking schizophrenia to abnormal structural and functional connectivity in the brain at both microscopic and macroscopic levels. Over the past few years, advances in high-field structural and functional neuroimaging techniques have made it increasingly feasible to reconstruct comprehensive maps of the macroscopic neural wiring system of the human brain, know as the connectome. In parallel, advances in network science and graph theory have improved our ability to study the spatial and topological organizational layout of such neural connectivity maps in detail. Combined, the field of neural connectomics has created a novel platform that provides a deeper understanding of the overall organization of brain wiring, its relation to healthy brain function and human cognition, and conversely, how brain disorders such as schizophrenia arise from abnormal brain network wiring and dynamics. In this review we discuss recent findings of connectomic studies in schizophrenia that examine how the disorder relates to disruptions of brain connectivity.     

Cognitive control and the COMT Val158Met polymorphism: genetic modulation of videogame training and transfer to task-switching efficiency

The study investigated whether successful transfer of game-based cognitive improvements to untrained tasks might be modulated by preexisting neuro-developmental factors, such as genetic variability related to the catechol-O-methyltransferase (COMT)—an enzyme responsible for the degradation of dopamine. The COMT Val¹⁵⁸Met genotype may differentially affect cognitive stability and flexibility, and we hypothesized that Val/Val homozygous individuals (who possess low prefrontal dopamine levels) show more pronounced cognitive flexibility than Met/-carriers (who possess high prefrontal dopamine levels). We trained participants, genotyped for the COMT Val¹⁵⁸Met polymorphism on playing “Half-Life 2”, a first-person shooter game which has been shown to improve cognitive flexibility. Pre-training (baseline) and post-training measures of cognitive flexibility were acquired by means of a task-switching paradigm. As expected, Val/Val homozygous individuals showed larger beneficial transfer effects than Met/-carriers. Our findings support the idea that genetic predisposition modulates transfer effects and that playing first-person shooter games promotes cognitive flexibility in individuals with a suitable genetic predisposition.     

The Importance of Written Information Packages in Support of Case-Finding Within Families at Risk for Inherited High Cholesterol

Inherited High Cholesterol is treatable, but highly underdiagnosed. To detect undiagnosed blood relatives at a presymptomatic stage, in the Netherlands written information packages are available to facilitate family communication. To investigate the role of those packages in the detection of carriers, we conducted a qualitative evaluation (plus-minus method combined with semistructured interviews with index patients and relatives). Our data suggest that interviewees approved the family approach for finding carriers, although reluctantly. The packages aided family disclosure by reducing hesitation. However, index patients only informed first-degree relatives and generally communicated the risk only once. This may be due to the cultural context and a limited understanding of genetics. For relatives the packages served as a cue to action and as a legitimation to gain access to a diagnostic cholesterol test. Despite the value of these written materials, they should not be used as the only communication between index patient and relatives.     

Automatic negative evaluation of suffocation sensations in individuals with suffocation fear

The current study tested whether "suffocation sensations" (respiratory loads) are automatically evaluated in a negative way by people fearing these sensations. It was found that, after having been primed with a slight respiratory load, participants with high suffocation fear (n=15) reacted more quickly to suffocation words and more slowly to positive words than participants with low suffocation fear (n=21). However, the effect was present only in participants who had noticed the primes. The findings are relevant to the cognitive model of panic disorder because automatic negative appraisal of sensations may play a role in initiating a panic attack.     

The computational implementation of the landscape model: Modeling inferential processes and memory representations of text comprehension

The complexity of text comprehension demands a computational approach to describe the cognitive processes involved. In this article, we present the computational implementation of the landscape model of reading. This model captures both on-line comprehension processes during reading and the off-line memory representation after reading is completed, incorporating both memory-based and coherence-based mechanisms of comprehension. The overall architecture and specific parameters of the program are described, and a running example is provided. Several studies comparing computational and behavioral data indicate that the implemented model is able to account for cycle-by-cycle comprehension processes and memory for a variety of text types and reading situations.     

Brief report: Teaching persons with moderate mental retardation to use printed instructions and time cues in a work context

Printed instructions and programable watches were used for helping two adults with moderate mental retardation perform variable tasks and follow a time schedule for task execution. The subjects, who could not read, were to match the words appearing in instruction notes to identical words superimposed on illustrative pictures (and collected in a vocabulary form). The pictures identified through this matching explained the meaning of the words being matched (i.e., indicated to the subjects which responses/tasks to perform). Self-recording was also used. The results showed that both subjects learned to use the printed instructions and the watches successfully. The subjects' performance remained positive over time. Procedural aspects and practical implications of the study are discussed.     

Locus of control and adjustment to cancer

The English form of the Cancer Locus of Control Scale was administered to an heterogeneous sample of 68 cancer patients. A principal components analysis confirmed the three subscales described in the original Dutch form, however, with five items excluded. Correlations with other measures indicated that high internal control over the course of the illness was associated with a tendency to adopt an attitude toward cancer of 'fighting spirit' whereas high internal control over the cause of the illness was associated with an 'anxious preoccupation' about cancer. No specific relationship was found between scale scores and either depression and anxiety or the tendency to be emotionally controlled. It was concluded that the scale provides a valid measure of perceptions of control of cancer patients and is a useful method of assessing these important psychological responses.     

“Out of disegno invention is born” — Drawing a convincing figure in Renaissance Italian Art

An important artistic topic of Italian Renaissance painting was the rendering of the human figure. As leading actors in a painted narrative, figures had to convince beholders of the reality of the matter depicted with appropriated attitudes and gestures. This article is about two ways of drawing or rather constructing the human figure artists developed to achieve this goal. The first was only an adaptation to an old method: because of the rather simple and coarse elements used, constructions often resulted in faulty pictures and were for that matter often criticized. As this article will show, the second method involved a new and very successful drawing skill, which not just required a different kind of knowledge of visual forms but of procedures of moving the hand, too.This article is a summary of the central thesis of my dissertationSporen van vaardigheid. De ontwerpmethode voor de figuurhouding in de Italiaanse tekenkunst van de renaissance, Abcoude 1991, which was published only in Dutch. I would like to thank A.Gasten for her help in translating the text of this article.     

Toward a rodent model of the Iowa gambling task

The Iowa gambling task in humans is, in principle, suited for the study of the long-term efficiency of behavior in a biologically relevant context. Key features of this task are uncertainty of outcomes and a conflict between the immediate and the long-term payoff options. Animal models allow us to study the underlying neurobiology of decision-making processes and the long-term efficiency of behavior in more detail and at a greater depth than is possible in humans. Therefore, we set out to develop a model of this task in rodents, using the task’s key features. In this article, we describe the results of the first series of experiments with rats and mice. The data thus far suggest that mice and rats behave in a way similar to humans; that is, they tend to choose the option with the best long-term payoff more often as the test progresses.