The role of general and number-specific order processing in adults’ arithmetic performance

Digit order processing is highly related to individual differences in arithmetic performance. To examine whether serial scanning or associative mechanisms underlie order processing, order tasks (i.e. deciding whether three digits were presented in an order or not) were administered in two experiments. In the first experiment, digits were presented in different directions namely ascending, descending and non-ordered. For each direction, close and far distance sequences were presented. Results revealed reversed distance effects for ordered sequences, but ascending sequences elicited faster performance and stronger reversed distance effects than descending sequences, suggesting that associative mechanisms underlie order processing. In the second experiment, it was examined to which extent the relation between order processing and arithmetic is number-specific by presenting order tasks with digits, letters and months. In all order tasks similar distance effects were observed and similar relations with arithmetic were found, suggesting that both general associative mechanisms and number-specific mechanisms contribute to arithmetic.     

Understanding sustainability

Proposed solutions to sustainability often bring different economic sectors into conflict; when a sustainable solution for one sector is non-sustainable for another it creates what we call the dilemma of sustainability. A recent example took place in the Columbia Basin of the Pacific Northwest, involving competing notions of sustainability by fisheries and the energy industry. Taking up some ideas of Eger and Lyotard, we criticize the constructivist approach which treats large ecosystems as constructions and the process of resolving conflicts of sustainability as one solely consisting of negotiations involving the trading off of interests. We propose instead to treat such conflict resolution via a Gadamerian-inspired hermeneutics that sees different economic sectors as having different interpretations of sustainability and that aims at common understanding.     

Understanding sustainability

Proposed solutions to sustainability often bring different economic sectors into conflict; when a sustainable solution for one sector is non-sustainable for another it creates what we call the dilemma of sustainability. A recent example took place in the Columbia Basin of the Pacific Northwest, involving competing notions of sustainability by fisheries and the energy industry. Taking up some ideas of Eger and Lyotard, we criticize the constructivist approach which treats large ecosystems as constructions and the process of resolving conflicts of sustainability as one solely consisting of negotiations involving the trading off of interests. We propose instead to treat such conflict resolution via a Gadamerian-inspired hermeneutics that sees different economic sectors as having different interpretations of sustainability and that aims at common understanding.     

Parental coping with their child's death

The impact of the death of 19 children form malignancy on subsequent patterns of parental coping was evaluated in a retrospective study of 33 Dutch parents, who had been bereaved for 19 months on average. Parents who had lost older children were compared with those who had lost younger ones on the Utrecht Coping List, which has been compared with a Dutch norm group. Coping styles of the bereaved parents differed significantly from those of the norm group. These differences were associated with the poorer mental health of the bereaved group as a whole. Parents of older children coped less well than those of younger ones.     

Further evidence that the SNARC effect is processed along a dual-route architecture: Evidence from the lateralized readiness potential

In a binary response setting, it has been frequently observed that small numbers are reacted to faster with the left hand and large numbers with the right hand (i. e., the SNARC-effect) which reflects the spatial left-right orientation of the mental number line (Dehaene, Bossini, & Giraux, 1993). In line with the work of Keus and Schwarz (in press), we investigated the locus of the conflict in the SNARC effect in a parity judgment task with the Arabic numerals 1, 2, 8, or 9. Differences between compatible (left-hand response to 1 or 2 and right-hand response to 8 and 9) and incompatible SNARC conditions (left-hand response to 8 or 9 and right-hand response to 1 or 2) were observed in the lateralized readiness potential (LRP) but not in the peak latency of the P300. In accordance with Keus and colleagues (Keus, Jenks, & Schwarz, 2005), we argue that the locus of the conflict is situated at intermediate response-related stages. However, instead of adopting a single-route processing architecture, a dual route account is proposed as the underlying processing architecture explaining the SNARC effect.     

Subjective visibility depends on level of processing

Is visual awareness graded or binary? Experimental work has provided support for both possibilities, leading to two coexisting but contradictory theoretical accounts. Here we propose a promising candidate factor through which to integrate both accounts: the depth of stimulus processing required by the task. We compared color identification (a low-level task) with numerical judgements (a high-level task) performed on the very same colored number stimuli. Psychophysical curves were analyzed for both objective discrimination performance and subjective visibility ratings on a trial-by trial basis. We observed a graded relationship between stimulus duration and visibility in the low-level task, but a more non-linear relationship in the high-level task. Both patterns of results have previously been consistently associated with the graded and the dichotomous account, respectively. Follow-up experiments that manipulate the level of processing can further unify previously inconsistent results, thus integrating two major theories of visual awareness.     

Job crafting and extra-role behavior: The role of work engagement and flourishing

This study investigates whether crafting of job demands and resources relates positively to extra-role behavior (i.e. contextual performance and creativity) through work engagement and flourishing. We collected data from 294 employees and their supervisors regarding employees' contextual performance and creativity. Results show that seeking resources had a positive indirect relationship with contextual performance through work engagement, and with creativity through work engagement and flourishing. Reducing demands had negative indirect relationships with both contextual performance and creativity through work engagement. We conclude that particularly seeking resources has important implications for extra-role behavior and discuss the practical implications of these findings.     

Towards a common processing architecture underlying Simon and SNARC effects

It has been shown repeatedly that relatively small numbers are responded to faster with the left hand and relatively large numbers are responded to faster with the right hand. This so-called SNARC effect (Dehaene, Bossini, & Giraux, 1993) is thought to arise through activation of irrelevant spatial codes associated with the magnitude of the number. This conflict between irrelevant magnitude information and the response is conceptually similar to the well-known Simon effect. Recently, both Mapelli, Rusconi, and Umiltà (2003) and Keus and Schwarz (in press) directly compared both effects in a single task within the framework of the additive factor method (Sternberg, 1969). While Mapelli et al. found additive effects of SNARC and Simon levels, suggesting different processing stages, Keus and Schwarz found that the SNARC effect depended on the compatibility level of the Simon task leading them to propose a common origin at the response selection stage. In the present study we demonstrate in 2 experiments that the relationship between Simon and SNARC depends on the relevance of the magnitude code, thereby violating one of the core assumptions of the AFM. Instead we propose a temporal overlap model to interpret the relationship between these effects which allows to commensurate apparently divergent outcomes.     

Dissecting the symbolic distance effect: Comparison and priming effects in numerical and nonnumerical orders

When participants are asked to compare two stimuli, responses are slower for stimuli close to each other on the relevant dimension than for stimuli further apart. Previously, it has been proposed that this comparison distance effect originates from overlap in the representation of the stimuli. This idea is generally accepted in numerical cognition, where it is assumed that representational overlap of numbers on a mental number line accounts for the effect (e.g., Cohen Kadosh et al., 2005). In contrast, others have emphasized the role of response-related processes to explain the comparison distance effect (e.g., Banks, 1977). In the present study, numbers and letters are used to show that the comparison distance effect can be dissociated from a more direct behavioral signature of representational overlap, the priming distance effect. The implication is that a comparison distance effect does not imply representational overlap. An interpretation is given in terms of a recently proposed model of quantity comparison (Verguts, Fias, & Stevens, 2005).     

Ethical, Legal and Social Aspects of Brain-Implants Using Nano-Scale Materials and Techniques

Nanotechnology is an important platform technology which will add new features like improved biocompatibility, smaller size, and more sophisticated electronics to neuro-implants improving their therapeutic potential. Especially in view of possible advantages for patients, research and development of nanotechnologically improved neuro implants is a moral obligation. However, the development of brain implants by itself touches many ethical, social and legal issues, which also apply in a specific way to devices enabled or improved by nanotechnology. For researchers developing nanotechnology such issues are rather distant from their daily work in the lab, but as soon as they use their materials or devices in medical applications such as therapy of brain diseases they have to be aware of and deal with them. This paper is intended to raise sensitivity for the ethical, legal and social aspects (ELSA) involved in applying nanotechnology in brain implants or other devices by highlighting the short term problems of testing and clinical trials within the existing regulatory frameworks (A), the short and medium-term questions of risks in the application of the devices (B) and the long-term perspectives related to problems of enhancement (C). To identify and address such issues properly nanotechnologists should involve ethical, legal and social experts and regulatory bodies in their research as early as possible. This will help to remove pressure from regulatory bodies, to settle public concern and to prevent non-acceptable developments for the benefit of the patients.