ALTSim: A MATLAB simulator for current associative learning theories

ALTSim is a MATLAB-based simulator of several associative learning models, including Pearce’s configural model, the extended configural model, the Rescorla-Wagner model, the unique cue hypothesis, the modified unique cue hypothesis, the replaced elements model, and Harris’s elemental model. It allows for specifying all relevant parameters, as well as exact stimulus sequences by graphical user interfaces. It is an easy-to-use tool that facilitates evaluating and comparing the featured associative learning models. ALTSim is available free of charge from www.staff.uni-marburg.de/~lachnit/ALTSim/.     

A longitudinal panel study on antecedents and outcomes of work-home interference

Theoretical models of the antecedents and outcomes of work-home interference (WHI) suggest that work characteristics (e.g., job stressors, working hours) increase the probability that an individual experiences work-home interference. Since work-home interference is considered as a role stressor, these experiences should be detrimental for long-term well-being. In this 2-wave panel study, the authors compared this suggested pathway with competing models that propose reverse causation and reciprocal effects in a sample of 365 employees (N at T2 = 130) from the German workforce using structural equation modeling. In particular, a model with two proposed antecedents (job stressors, working hours) of WHI and two proposed consequences (depression, turnover motivation) was analyzed in alternative configurations. The results support a cyclical model with a job stressors → depression → WHI → job stressors pathway. Furthermore, working hours affected WHI, and turnover motivation emerged as an outcome of WHI.     

Age differences in sensation seeking and impulsivity as indexed by behavior and self-report: evidence for a dual systems model

It has been hypothesized that sensation seeking and impulsivity, which are often conflated, in fact develop along different timetables and have different neural underpinnings, and that the difference in their timetables helps account for heightened risk taking during adolescence. In order to test these propositions, the authors examined age differences in sensation seeking and impulsivity in a socioeconomically and ethnically diverse sample of 935 individuals between the ages of 10 and 30, using self-report and behavioral measures of each construct. Consistent with the authors' predictions, age differences in sensation seeking, which are linked to pubertal maturation, follow a curvilinear pattern, with sensation seeking increasing between 10 and 15 and declining or remaining stable thereafter. In contrast, age differences in impulsivity, which are unrelated to puberty, follow a linear pattern, with impulsivity declining steadily from age 10 on. Heightened vulnerability to risk taking in middle adolescence may be due to the combination of relatively higher inclinations to seek excitement and relatively immature capacities for self-control that are typical of this period of development.     

What determines creative association? Revealing two factors which separately influence the creative process when solving the Remote Associates Test

The Remote Associates Test is a well‐established measure, frequently used to assess individuals’ creative abilities, as a function of the ability to elicit remote associates. The nature of the involved associative processes is still poorly understood. This hampers a deeper understanding of the creative process, rendering it difficult to determine what factors are controlled for, when the RAT is employed. We report an experiment that sheds further light on the nature of the associative process by manipulating (a) the frequency with which a pair of items are associated as associative strength, and (b) the probability of reaching the answer given the strength and the spread. Experimental results indicate a clear and surprisingly separate influence of frequency and probability on accuracy and response times. Frequency and probability both are thus factors that need to be included in the modeling process and controlled for when using the RAT to assess creativity.     

„Was ist Wissenschaft? Darstellung und Bestandsaufnahme der deutschen Wissenschaftsphilosophie“; Wissenschaftszentrum Bonn, 17–19. März 2008

Ohne Zusammenfassung     

Child-care history, classroom composition, and children's functioning in kindergarten

Previous research indicates that exposure to nonparental child care at an earlier age and for more hours predicts, at the individual level, more aggressive and disobedient behavior and greater school preparedness. The present study extended child-care research by investigating classroom-composition effects, that is, effects of the combined child-care histories of all the children in the classroom. Analyses showed that effects at the individual level aggregate at the classroom level: Kindergarten children with limited or no child-care history exhibited more externalizing behavior (e.g., fighting and arguing) and higher academic achievement when schooled in classrooms with more peers who had extensive child-care histories.     

Emotional irritation before mental stress is associated with enhanced peripheral norepinephrine

Research suggests equivocal findings on associations of catecholamines and mood. Our study investigated the associations of emotional state, blood pressure and catecholamines in 55 healthy males undergoing mental stress. We especially checked the reported link between norepinephrine (NE) and emotional irritation. Blood pressure (SBP, DBP) and heart rate (HR) were continuously monitored. NE and epinephrine (EPI) were measured before, after, and 20 minutes after stress. Participants were divided into irritated versus non-irritated and anxious versus non-anxious subjects by median split on their baseline questionnaires. The task elicited significant cardiovascular, hormonal, and psychological stress responses. NE levels were significantly correlated with irritation before stress. Irritated subjects showed significantly higher DBP and NE than non-irritated subjects. The higher NE and DBP levels in the irritated participants suggest detrimental psycho-physiological interrelations promoting the development of stress-mediated cardiovascular diseases. Heightened emotional irritation before stress may be regarded as a psychological risk factor.     

Threats of violence in group-oriented day treatment

Threats of violence in a group-oriented day treatment program are examined regarding the patient's motivation to make threats, and what occurs among patients and staff that fosters threats. Effects of threats on other patients, the program, and therapists are considered. Management of the threatening patient, the group, and staff reactions are described. Safety of group members is a sine qua non for the groups to function effectively.     

Eye movements and behavioral responses to threatening and nonthreatening stimuli during visual search in phobic and nonphobic subjects

Spider-phobic and nonphobic subjects searched for a feared/fear-relevant (spider) or neutral target (mushroom) presented in visual matrices of neutral objects (flowers). In half of the displays, the mushroom target was paired with a spider distractor, or a spider target was paired with a mushroom distractor. Although all subjects responded faster to the neutral target than to the feared/fear-relevant target, phobics were slower to respond than nonphobics when a mushroom target was presented with a spider distractor. Their eyes appeared to be drawn to the feared distractor before fixating neutral targets. A further experiment indicated no group differences when subjects merely judged the homogeneity of matrices. Thus, threat seems to capture the attention of phobics only when it is part of a background that subjects are explicitly instructed to ignore.