Crossed-uncrossed difference (CUD) on reaction time and movement time in three two-choice experiments

The present study addresses the robustness and the reliability of the crossed-uncrossed difference (CUD) on a reaction time (RT) and a movement time (MT) component of a prescribed unimanual response to lateralized stimuli. Experiment 1 demonstrated positive CUDs both when a visual warning signal (WS) and an auditory reaction signal (RS) appeared on corresponding and non-corresponding sides of the body. Experiment 2 showed effect of handedness on CUD calculated among right-handers and left-handers. Experiment 3 investigated CUDs through five successive days, indicating that CUDs became steady and reliable although practice affected both RT and MT. All experiments indicated CUD on RT and MT. In addition, Experiments 1 and 2 demonstrated hemispheric asymmetries in favour of an anatomical theory while Experiment 3 did not show any asymmetries and supports an S-R compatibility theory.     

EXPLAINING EMERGENCE: TOWARDS AN ONTOLOGY OF LEVELS

The vitalism/reductionism debate in the life sciences shows that the idea of emergence as something principally unexplainable will often be falsified by the development of science. Nevertheless, the concept of emergence keeps reappearing in various sciences, and cannot easily be dispensed with in an evolutionary world-view. We argue that what is needed is an ontological non reductionist theory of levels of reality which includes a concept of emergence, and which can support an evolutionary account of the origin of levels. Classical explication of emergence as “the creation of new properties” is discussed critically, and specific distinctions between various kinds of emergence is introduced for the purpose of developing an ontology of levels, framed in a materialistic and evolutionary perspective. A concept of the relation between levels as being inclusive is suggested, permitting the “local” existence of different ontologies. We identify, as a working hypothesis, four primary levels and explicate their nonhomomorphic interlevel relations. Explainability of emergence in relation to determinism and predictability is considered. Recent research in self-organizing non-linear dynamical systems represents a revival of the scientific study of emergence, and we argue that these recent developments can be seen as a step toward a final “devitalisation” of emergence.     

Perceptual and motor components of performance in three different reaction time experiments

Three reaction time experiments were conducted to examine the effects of time of day, stimulus intensity, stimulus modality, and constant and variable foreperiod on the perceptual and motor components of performance. These variables are all supposed to generate changes in arousal level. All the independent variables affected the perceptual component, while the motor component was significantly influenced only by foreperiod and modality. The results are discussed in relation to aspects of dependency/independency of the perceptual and motor components of human performance in reaction time experiments.     

Childhood Adverse Experience: Yes or No? Mothers' Decision-Making Process When Responding to Survey Questions

The aim of this pilot study was to assess how difficult it is for mothers to answer questions regarding adversities their children might have experienced, and to investigate their considerations in the decision-making process. A nonrepresentative community sample of 628 mothers of 6- to 8-year-old children responded to an online survey. The mothers answered questions regarding adversities, rated the acceptability of these questions, and reported on any difficulties they had in responding. Based on the mothers' reports, qualitative analyses were conducted to identify metacategories of arguments. The study highlights the need for increased awareness of the complexity involved in soliciting information about adverse experiences in research and clinical settings, and for caution in interpreting epidemiological results in this field.     

Adolescent Suicide Attempters: What Predicts Future Suicidal Acts?

Predictors for repetition of suicide attempts were evaluated among 92 adolescent suicide attempters 9 years after an index suicide attempt (90% females). Five were dead, two by suicide. Thirty-one (42%) of 73 had repeated a suicide attempt. In multiple Cox regression analysis, four factors had an independent predictive effect: comorbid disorders, hopelessness, having ever received treatment for mental or behavior problems, and having a father exerting control without affection. Prediction on an individual level was difficult. Since almost half repeated a suicidal act, the best strategy is to evaluate all adolescent suicide attempters thoroughly and provide treatment as needed.