System consolidation of memory during sleep

Over the past two decades, research has accumulated compelling evidence that sleep supports the formation of long-term memory. The standard two-stage memory model that has been originally elaborated for declarative memory assumes that new memories are transiently encoded into a temporary store (represented by the hippocampus in the declarative memory system) before they are gradually transferred into a long-term store (mainly represented by the neocortex), or are forgotten. Based on this model, we propose that sleep, as an offline mode of brain processing, serves the ‘active system consolidation’ of memory, i.e. the process in which newly encoded memory representations become redistributed to other neuron networks serving as long-term store. System consolidation takes place during slow-wave sleep (SWS) rather than rapid eye movement (REM) sleep. The concept of active system consolidation during sleep implicates that (a) memories are reactivated during sleep to be consolidated, (b) the consolidation process during sleep is selective inasmuch as it does not enhance every memory, and (c) memories, when transferred to the long-term store undergo qualitative changes. Experimental evidence for these three central implications is provided: It has been shown that reactivation of memories during SWS plays a causal role for consolidation, that sleep and specifically SWS consolidates preferentially memories with relevance for future plans, and that sleep produces qualitative changes in memory representations such that the extraction of explicit and conscious knowledge from implicitly learned materials is facilitated.     

On the role of beliefs in observational flavor conditioning

In previous research (Baeyens, Vansteenwegen et al., 1996) we demonstrated that when observers consume a series of CS+ and CS−flavored drinks while simultaneously watching a videotaped model who synchronically drinks identical drinks and facially expresses his evaluation (dislike to CS+, neutral to CS−) of the liquids, the observers acquire a dislike for CS+ flavored relative to CS−flavored drinks. The aim of the present experiments was to test some predictions derived from a “direct conditioning” theory of such observational flavor learning. Using the same observational flavor conditioning procedure, we investigated (Exp. 1) the effect of manipulating the observers’ belief concerning the relationship between the drinks that they and the model were consuming (same/different/no information). Observational flavor conditioning was obtained when observers were led to believe that they were drinking the same drinks as the model did, and when they were not informed about this relationship, but not when told to be drinking different drinks. At the same time, however, the observers were not able to correctly identify the source of the model’s expression of dislike: They showed no CS-US contingency-awareness. Whereas the former finding suggests the causal involvement of conscious beliefs and cognitive inference processes in observational learning, the latter is more in line with the idea that the model’s facial expressions may act like a US’ which is automatically associated with the paired flavor CS+, without any involvement of conscious beliefs or cognitive inferences. These two crucial findings were replicated in Exp. 2. Also, we obtained evidence in this study that the belief manipulation affected learning through its influence on the observers’ attention for the model’s facial evaluative expressions. These results can be integrated either by a cognitive theory allowing the beliefs on which the inferences are based to be of an implicit nature, or by a “direct conditioning” theory that conceives of the US’ as an interpreted event, rather than as a mechanistically and invariantly acting physical entity.     

The logical investigations of jan kalicki

This paper describes the work of the Polish logician Jan Kalicki (1922–1953). After a biographical introduction, his work on logical matrices and equational logic is appraised. A bibliography of his papers and reviews is also included.     

Stop what you are not doing! Emotional pictures interfere with the task not to respond

Previous research has shown that emotional stimuli interfere with ongoing activities. One explanation is that these stimuli draw attention away from the primary task and thereby hamper the correct execution of the task. Another explanation is that emotional stimuli cause a temporary freezing of all ongoing activity. We used a go/ no-go task to differentiate between these accounts. According to the attention account, emotional distractors should impair performance on both go and no-go trials. According to the freezing account, the presentation of emotional stimuli should be detrimental to performance on go trials, but beneficial for performance on no-go trials. Our findings confirm the former prediction: Pictures high in emotional arousal impaired performance on no-go trials.     

Rejection Sensitivity and the Rejection–Hostility Link in Romantic Relationships

ABSTRACT Rejection sensitivity is the disposition to anxiously expect, readily perceive, and intensely react to rejection. In response to perceived social exclusion, highly rejection sensitive people react with increased hostile feelings toward others and are more likely to show reactive aggression than less rejection sensitive people in the same situation. This paper summarizes work on rejection sensitivity that has provided evidence for the link between anxious expectations of rejection and hostility after rejection. We review evidence that rejection sensitivity functions as a defensive motivational system. Thus, we link rejection sensitivity to attentional and perceptual processes that underlie the processing of social information. A range of experimental and diary studies shows that perceiving rejection triggers hostility and aggressive behavior in rejection sensitive people. We review studies that show that this hostility and reactive aggression can perpetuate a vicious cycle by eliciting rejection from those who rejection sensitive people value most. Finally, we summarize recent work suggesting that this cycle can be interrupted with generalized self-regulatory skills and the experience of positive, supportive relationships.     

Causal ordering of academic self‐concept and achievement: Effects of type of achievement measure

Background. The relation between academic self‐concept and achievement has been examined in a large number of studies. The majority of these studies have found evidence for a reciprocal effects model. However, there is an ongoing debate on how students' achievement should be measured and whether the type of achievement indicator (grades, tests, teacher ratings) affects the causal pattern found in these studies. Aims. The study aims at clarifying how the types of achievement measures and the way they are modelled can affect the results of causal ordering studies. In that sense, the study will yield recommendations for researchers in this domain and also provide some direction for practitioners seeking ways to enhance their students' achievement and/or academic self‐concept. Sample. Repeated measures of academic self‐concept and achievement (standardized tests and teacher ratings) were examined in a sample of 1,753 students in Grades 7, 8, 10, and 12. Method. Structural equation modelling was used. Several models (with different types and numbers of achievement measures) were compared. Results. Only small differences were found between models using one or two indicators of achievement. All models generally supported the reciprocal effects model. However, the final model, wherein tests and teacher ratings were used as separate latent variables, showed different developmental patterns in the causal relation between academic self‐concept and achievement. Conclusions. Researchers should interpret the results of causal ordering studies discerningly because the type of measure chosen as an indicator of achievement might affect the causal pattern between academic self‐concept and achievement.     

Perceptual simulation in developing language comprehension

We tested an embodied account of language proposing that comprehenders create perceptual simulations of the events they hear and read about. In Experiment 1, children (ages 7–13 years) performed a picture verification task. Each picture was preceded by a prerecorded spoken sentence describing an entity whose shape or orientation matched or mismatched the depicted object. Responses were faster for matching pictures, suggesting that participants had formed perceptual-like situation models of the sentences. The advantage for matching pictures did not increase with age. Experiment 2 extended these findings to the domain of written language. Participants (ages 7–10 years) of high and low word reading ability verified pictures after reading sentences aloud. The results suggest that even when reading is effortful, children construct a perceptual simulation of the described events. We propose that perceptual simulation plays a more central role in developing language comprehension than was previously thought.     

Everyday risk taking as a function of regulatory focus

Uncertainty is an inherent aspect of everyday life. However, faced with uncertainty, some individuals take risks more eagerly than others. Regulatory focus theory may explain such differences because risky behavior may arise naturally from the eagerness of promotion focused individuals, while safe behavior may arise naturally from the vigilance of prevention focused individuals. A highly relevant real-life context for studying risk is mobility, as engaging in traffic inherently carries uncertainty about negative outcomes. We present two studies showing a direct link between regulatory focus and risky behavior going beyond traditional laboratory approaches. In both naturalistic speeding behavior (Study 1) and simulated risk taking (Study 2) promotion focus was positively, and prevention focus was negatively related to actual risky behavior.     

Deciding where to attend: priming of pop-out drives target selection

With attention and eye-movements humans orient to targets of interest. This orienting occurs faster when the same target repeats: priming of pop-out (PoP). While reaction times (RTs) can be important, PoP's real function could be to steer where to orient, a possibility underexposed in many current paradigms, as these predesignate a target to which to orient. In a novel procedure we intermixed pop-out trials (one oddball target, two identical distractors) with choice trials (one item of each kind) where observers freely chose an item to attend to. Pop-out trials strongly drove subsequent choice: observers typically chose the preceding target. Conversely, choice trials affected subsequent pop-out RTs. Conventional PoP measures correlated positively with our choice measures among observers, suggesting common mechanisms. Our results support PoP accounts centered on altered target priority, and underscore PoP's importance for visual exploration.