Contents of Volume 14

Volume Contents

Contents of Volume 14     

The locus of adaptation to altered gain in aimed movements

Altered gain settings cause a mismatch between the actual movement amplitude across the surface and the distance covered on a real time visual display. The present study pursued three objectives of how adaptation to altered gain affects aimed motor behavior. First, we replicated findings of an earlier study reporting a negative linear relation between gain and both target acquisition time and end-point variability. This means that our data do not agree with the classic U-shaped relation between gain and acquisition time. Second, our results proved to be robust when we manipulated movement difficulty by varying target distance. And third, dividing a movement into four successive sections on the basis of key kinematic events revealed the locus of the adaptation to altered gain within movement execution. Time differences between gain conditions proved to start at a very early part of the movement, but appeared to be absent in the final movement section. In contrast, differences between gain conditions regarding the use of online feedback were also present in the last part of the movement during which the final target approach takes place.     

Phonological and morphological consistency in the acquisition of vowel duration spelling in Dutch and German

In Dutch, vowel duration spelling is phonologically consistent but morphologically inconsistent (e.g., paar-paren). In German, it is phonologically inconsistent but morphologically consistent (e.g., Paar-Paare). Contrasting the two orthographies allowed us to examine the role of phonological and morphological consistency in the acquisition of the same orthographic feature. Dutch and German children in Grades 2 to 4 spelled singular and plural word forms and in a second task identified the correct spelling of singular and plural forms of the same nonword. Dutch children were better in word spelling, but German children outperformed the Dutch children in nonword selection. Also, whereas German children performed on a similar level for singular and plural items, Dutch children showed a large discrepancy. The results indicate that children use phonological and morphological rules from an early age but that the developmental balance between the two sources of information is constrained by the specific orthography.     

Developmental dyslexia and discrimination in speech perception: a dynamic model study

At the behavioral level one of the primary disturbances involved in congenital dyslexia concerns phonological processing. At the neuroarchitectural level autopsies have revealed ectopies, e.g., a reduced number of neurons in the upper layers of the cortex and an increased number in the lower ones. In dynamic models of interacting neuronal populations the behavioral level can be related to the neurophysiological level. In this study an attempt is made to do so at the cortical level. The first focus of this model study are the results of a Finnish experiment assessing geminate stop perception in quasi speech stimuli by 6 month old infants using a head turning paradigm and evoked potentials. The second focus of this study are the results of a Dutch experiment assessing discrimination of transients in speech stimuli, by adult dyslexics and controls and 2 month old infants. There appears to be a difference in the phonemic perceptual boundaries of children at genetic risk for dyslexia and control children as revealed in the Finnish study. Assuming a lowered neuronal density in the 'dyslexic' model, reflecting ectopies, it may be postulated that less neuronal surface is available for synaptic connections resulting in a lowered synaptic density and thus a lowered amount of available neurotransmitter. A lowered synaptic density also implies a reduced amount of membrane surface available for neurotransmitter metabolism. By assuming both, a reduced upper bound of neurotransmitter and a reduced metabolic transmitter rate in the dynamic model, the Finnish experimental results can be approximated closely. This applies both to data from behavioral head turning and that of the evoked potential study. In the Dutch study adult dyslexics show poor performance in discriminating transients in the speech signal compared to the controls. The same stimuli were used in a a study comparing infants from dyslexic families and controls. Using the same transmitter parameters as in modeling the results of the Finnish study, also in this case the experimental results for adults and infants can be approximated closely. Simulation of behavioral and pharmaceutical interventions with the model provide predictions which can be put to the test in experiments.     

The assignment of scores for output‐based research funding

This paper considers the assignment of scores to research output items, such as articles, books, contributions to conference proceedings, doctoral dissertations, etc., under four distribution criteria: the advancement of pure and applied scientific research, the advancement of innovative problem solving, the dissemination of scientific knowledge, and the coverage of the cost of the research. These scores are to be used in the allocation of research funds to the faculties of a university. The present paper describes the experiments carried out within the framework of the Decision Analysis and Support Project of the International Institute of Applied Systems Analysis, Laxenburg, Austria. It summarizes the vivid discussions triggered by the experiment, and it also presents the results of an additional experiment. Copyright © 1999 John Wiley & Sons, Ltd.     

Sound improves diminished visual temporal sensitivity in schizophrenia

Visual temporal processing and multisensory integration (MSI) of sound and vision were examined in individuals with schizophrenia using a visual temporal order judgment (TOJ) task. Compared to a non-psychiatric control group, persons with schizophrenia were less sensitive judging the temporal order of two successively presented visual stimuli. However, their sensitivity to visual temporal order improved as in the control group when two accessory sounds were added (temporal ventriloquism). These findings indicate that individuals with schizophrenia have diminished sensitivity to visual temporal order, but no deficits in the integration of low-level auditory and visual information.     

Under the Spell of the Ring

Among orthodox reformed Christians in the Netherlands fierce debates have occurred on moral aspects of Christian life. This essay discusses three major controversial moral issues that are related to conceptions of sex, gender, and sexuality: divorce/remarriage, women’s ordination, and homosexuality. By analysing several contributions to debates on these issues, it proposes and explores a hypothesis that concerns the role of a particular understanding of marriage as characterized by a hermeneutical construct: a communal, deeply rooted and subconscious normative principle that drives our interpretations of texts and practices. This essay illustrates the problems of both the dominance of marriage within Christian communities and lived faith, as well as the modern, romantic aspects of this particular understanding of marriage.     

The Problem of Many Hands: Climate Change as an Example

In some situations in which undesirable collective effects occur, it is very hard, if not impossible, to hold any individual reasonably responsible. Such a situation may be referred to as the problem of many hands. In this paper we investigate how the problem of many hands can best be understood and why, and when, it exactly constitutes a problem. After analyzing climate change as an example, we propose to define the problem of many hands as the occurrence of a gap in the distribution of responsibility that may be considered morally problematic. Whether a gap is morally problematic, we suggest, depends on the reasons why responsibility is distributed. This, in turn, depends, at least in part, on the sense of responsibility employed, a main distinction being that between backward-looking and forward-looking responsibility.     

The Ingredients of Aristotle’s Theory of Fallacy

In chapter 8 of the Sophistical Refutations, Aristotle claims that his theory of fallacy is complete in the sense that there cannot be more fallacies than the ones he lists. In this article I try to explain how Aristotle could have justified this completeness claim by analysing how he conceptualizes fallacies (dialectical mistakes which do not appear so) and what conceptual ingredients play a role in his discussion of fallacies. If we take the format of dialectical discussions into account, we will see that there are only so many mistakes one can make which still do not appear to be mistakes. Aristotle’s actual list is almost identical to these apparent mistakes.     

Innovativeness and initiative as mediators between achievement orientation and venture performance

A central question in entrepreneurship research is how to predict venture performance. In prior research, psychological characteristics of the entrepreneur and entrepreneurial behaviours have been more or less found to be able to distinguish between successful and unsuccessful entrepreneurs. The aim in this study was to extend earlier research and to test a model in which innovativeness and initiative are mediators between achievement orientation (including the psychological characteristics: self-efficacy, higher order need strength, need achievement, and internal locus of control) and venture performance. Data from 201 entrepreneurs were analysed with structural equation modelling to test the mediation model. The results suggest that innovativeness is a mediator between achievement orientation and venture performance, whereas initiative could not be confirmed as a mediator.