Working memory performance after acute exposure to the cold pressor stress in healthy volunteers

Effects of acute stress exposure on learning and memory have been frequently studied in both animals and humans. However, only a few studies have focused specifically on working memory performance and the available data are equivocal. The present study examined working memory performance during the Sternberg item recognition task after exposure to a predominantly adrenergic stressor. Twenty four healthy subjects were randomly assigned to a stress group or a control group. The stress group was exposed to the cold pressor stress test (CPS; i.e. insertion of the dominant hand into ice water for 60s), while 37 °C warm water was used with the control group. Twenty minutes after the stress exposure, working memory performance was tested with the Sternberg item recognition task with three levels of cognitive load. Sympathetic nervous system and hypothalamic pituitary adrenocortical (HPA) axis activation during CPS, were assessed by measuring heart rate and salivary cortisol before and during (heart rate) or 30 min after (cortisol) the stress procedure. Exposure to the CPS test was associated with a significant increase in heart rate but no increase in salivary cortisol. Participants exposed to the stress procedure showed significantly shorter reaction times during trials with higher cognitive load but tended to show higher false alarm rates than control subjects. The present results indicate that exposure to CPS can be associated with signs of both enhanced and impaired working memory performance. The observed behavioral pattern might represent a form of streamlined information processing advantageous in a threatening situation.     

Programmed to learn? The ontogeny of mirror neurons

Mirror neurons are increasingly recognized as a crucial substrate for many developmental processes, including imitation and social learning. Although there has been considerable progress in describing their function and localization in the primate and adult human brain, we still know little about their ontogeny. The idea that mirror neurons result from Hebbian learning while the child observes/hears his/her own actions has received remarkable empirical support in recent years. Here we add a new element to this proposal, by suggesting that the infant's perceptual‐motor system is optimized to provide the brain with the correct input for Hebbian learning, thus facilitating the association between the perception of actions and their corresponding motor programs. We review evidence that infants (1) have a marked visual preference for hands, (2) show cyclic movement patterns with a frequency that could be in the optimal range for enhanced Hebbian learning, and (3) show synchronized theta EEG (also known to favour synaptic Hebbian learning) in mirror cortical areas during self‐observation of grasping. These conditions, taken together, would allow mirror neurons for manual actions to develop quickly and reliably through experiential canalization. Our hypothesis provides a plausible pathway for the emergence of mirror neurons that integrates learning with genetic pre‐programming, suggesting new avenues for research on the link between synaptic processes and behaviour in ontogeny.     

Catechol-O-methyltransferase Val158Met genotype affects neural correlates of aversive stimuli processing

It was previously shown that variation of the catechol-O-methyltransferase (COMT) gene modulates brain activity during the processing of stimuli with negative valence, but not for pleasant stimuli. Here, we tested whether the COMT genotype also modulates the electrophysiological correlates of emotional processing and explored whether the environmental factor of life stress influences this effect. Using the early posterior negativity (EPN) paradigm, event-related brain potentials were measured in 81 healthy individuals during the processing of pictures that evoked emotions of positive and negative valence. As was hypothesized, the COMT genotype affected the EPN amplitudes for unpleasant stimuli, but not for pleasant ones. Specifically, Met/Met carriers respond more sensitively to unpleasant stimuli, as compared with Val/Val carriers. We did not find evidence that life stress moderates the effect of the COMT genotype on emotional stimuli processing.     

Keynote lectures (in alphabetical order, according to the lecturers’ last names)

Abstract

Keynote lectures (in alphabetical order, according to the lecturers’ last names)     

Can bad weather improve your memory? An unobtrusive field study of natural mood effects on real-life memory

Can good or bad mood induced by the weather influence people’s ability to correctly remember everyday scenes? In this unobtrusive field study, we predicted and found that weather-induced negative mood improved memory accuracy. Randomly selected shoppers on bright, sunny days (good mood) or on cloudy, rainy days (bad mood) saw 10 unusual objects in the check-out area of a suburban shop, and their recall and recognition memory for these objects was later tested. Shoppers in a negative mood showed better memory and higher discrimination ability. The cognitive mechanisms responsible for everyday mood effects on memory performance are discussed, and the implications of these findings for current affect/cognition theories and applied areas are considered.     

Object representations maintain attentional control settings across space and time

Previous research has revealed that we create and maintain mental representations for perceived objects on the basis of their spatiotemporal continuity. An important question is what type of information can be maintained within these so-called object files. We provide evidence that object files retain specific attentional control settings for items presented inside the object, even when it disappears from vision. The objects were entire visual search displays consisting of multiple items moving into and out of view. It was demonstrated that search was speeded when the search target position was repeated from trial to trial, but especially so when spatiotemporal continuity suggested that the entire display was the same object. We conclude that complete spatial attentional biases can be stored in an object file.     

Can intuition improve deception detection performance?

Two studies examined the role of processing style (intuitive vs. deliberative processing) in a deception detection task. In the first experiment, a thin slicing manipulation was used to demonstrate that intuitive processing can lead to more accurate judgments of deception when compared with traditional deliberative forms of processing. In the second experiment, participants who engaged in a secondary (concurrent) task performed more accurately in a deception detection task than participants who were asked to provide a verbal rationale for each decision and those in a control condition. Overall, the results converge to suggest that intuitive processing can significantly improve deception detection performance.     

The Salvational Process in Relationships: A View from Projective–Introjective Identification and Repetition Compulsion

On the basis of mechanisms such as projective–introjective identification, basic affect, affect regulation, and repetition compulsion, we shall try to explain the essence of intrapsychic, interpersonal, and relational family dynamics. We will also try to explain how relational connections mutually intertwine in the family system, what sustains them, and why they are created and recreated again and again. It is in this regard that we will also be able to consider the essential salvational process, which occurs precisely on the basis of these mechanisms, that is, those that represent fundamental purification and salvation. Some basic biblical theological concepts are applied. These provide the basis for integrating the psychological and theological domains of family systems.     

The conceptual centrality of causal cycles

How do causal cycles affect judgments of conceptual centrality? Generally, a feature is central to a concept to the extent that other features in the concept depend on it, thereby rendering it immutable from the concept (Sloman, Love, &; Ahn, 1998). Previous research on conceptual centrality has focused primarily on features involved in four major types of dependency structures: simple cause-effect relations, causal chains, common-cause structures, and common-effect structures. Causal cycles are a fifth type of dependency structure commonly reported in people’s real-life concepts, yet to date, they have been relatively ignored in research on conceptual centrality. The results of six experiments suggest that previously held assumptions about the conceptual representation of cycles are incorrect. We discuss the implications of these findings for our understanding of theory-based concepts.