Word associations: Network and semantic properties

A number of properties of word associations, generated in a continuous task, were investigated. First, we investigated the correspondence of word class in association cues and responses. Nouns were the modal word class response, regardless of the word class of the cue, indicating a dominant paradigmatic response style. Next, the word association data were used to build an associative network to investigate the centrality of nodes. The study of node centrality showed that central nodes in the network tended to be highly frequent and acquired early. Small-world properties of the association network were investigated and compared with a large English association network (Steyvers & Tenenbaum, 2005). Networks based on a multiple association procedure showed small-world properties despitebeing denser than networks based on a discrete task. Finally, a semantic taxonomy was used to investigate the composition of semantic types in association responses. The majority of responses were thematically related situation responses and entity responses referring to parts, shape, or color. Since the association task required multiple responses per cue, the interaction between generation position and semantic role could be investigated and discussed in the framework of recent theories of natural concept representations (Barsalou, Santos, Simmons, & Wilson, in press).     

Scaffolding the design of accessible eLearning content: a user-centered approach and cognitive perspective

There exist various guidelines for facilitating the design, preparation, and deployment of accessible eLearning applications and contents. However, such guidelines prevalently address accessibility in a rather technical sense, without giving sufficient consideration to the cognitive aspects and issues related to the use of eLearning materials by learners with disabilities. In this paper we describe how a user-centered design process was applied to develop a method and set of guidelines for didactical experts to scaffold their creation of accessible eLearning content, based on a more sound approach to accessibility. The paper also discusses possible design solutions for tools supporting eLearning content authors in the adoption and application of the proposed approach.     

In search of a comprehensive value model for assessing supplementary person-organization fit

In this study, the authors tested the comprehensiveness of the S. H. Schwartz (1992) value model as a conceptual framework for assessing supplementary person-organization fit. They conducted an extensive literature search in which they identified 42 value instruments or typologies that are used to measure life, work, or organizational values. Experts judged whether each of 1,578 items from these 42 instruments could be regarded as an indicator of 1 of the 10 value types identified by S. H. Schwartz (1992). The authors found that (a) 92.5% of the items could be classified into 1 of the 10 value types and (b) the remaining items suggested 2 possible new types (goal orientedness and relations). The authors also found indications that 2 value types could be split to obtain a more univocal meaning. Overall, these findings suggest that the S. H. Schwartz (1992) value model might be an appropriate comprehensive framework for studying supplementary person-organization fit.     

Promoting step responses of children with multiple disabilities through a walker device and microswitches with contingent stimuli

Children with severe or profound intellectual and motor disabilities often present problems of balance and locomotion and spend much of their time sitting or lying, with negative consequences for their development and social image. This study provides a replication of recent (pilot) studies using a walker (support) device and microswitches with preferred stimuli to promote locomotion in two children with multiple disabilities. One child used an ABAB design; the other only an AB sequence. Both succeeded in increasing their frequencies of step responses during the B (intervention) phase(s). These findings support the positive evidence already available on the effectiveness of this intervention in motivating and promoting children's locomotion.     

A Speeded Item Response Model with Gradual Process Change

An item response theory model for dealing with test speededness is proposed. The model consists of two random processes, a problem solving process and a random guessing process, with the random guessing gradually taking over from the problem solving process. The involved change point and change rate are considered random parameters in order to model examinee differences in both respects. The proposed model is evaluated on simulated data and in a case study. The research reported in this paper was supported by IAP P5/24 and GOA/2005/04, both awarded to Paul De Boeck and Iven Van Mechelen, and by IAP P6/03, awarded to Iven Van Mechelen. Yuri Goegebeur’s research was supported by a grant of the Danish Natural Science Research Council.     

Intrusiveness of Minorities: Growing Pains for the Majority Group?1

In this paper, we examined the impact of the numerical representation and the intrusiveness of immigrants on feelings of group threat voiced by the majority. The present evaluation of group threat differs from previous studies in its inclusion of temporal comparisons. The relationship between feelings of threat and attitudes toward immigration was also evaluated. In all, 221 college students completed a questionnaire. As predicted, results obtained show that numerical representation was positively associated with feelings of group threat resulting from invidious social comparisons. Intrusiveness was positively related to feelings of group threat resulting from temporal comparisons. Contrary to hypotheses, the final model confirms that only feelings of temporal group threat were associated with negative attitudes toward immigration. Practical implications and the important role of temporal comparisons are discussed.     

Learning to ignore: Acquisition of sustained attentional suppression

We examined whether the selection mechanisms committed to the suppression of ignored stimuli can be modified by experience to produce a sustained, rather than transient, change in behavior. Subjects repeatedly ignored the shape of stimuli, while attending to their color. On subsequent attention to shape, there was a robust and sustained decrement in performance that was selective to when shape was ignored across multiple-colortarget contexts, relative to a single-color-target context. Thus, amount of time ignored was not sufficient to induce a sustained performance decrement. Moreover, in this group, individual differences in initial color target selection were associated with the subsequent performance decrement when attending to previously ignored stimuli. Accompanying this sustained decrement in performance was a transfer in the locus of suppression from an exemplar (e.g., a circle) to a feature (i.e., shape) level of representation. These data suggest that learning can influence attentional selection by sustained attentional suppression of ignored stimuli.     

Dorsolateral prefrontal cortex and Stroop performance: Tackling the lateralization

Neuroscience research has identified the involvement of the dorsolateral prefrontal cortex (DLPFC) in cognitive control. Questions remain, however, about its lateralization correlates during Stroop task performance, an experimental cornerstone on which a large amount of cognitive control research is based. After reviewing the literature, we find that three Stroop variants have been used in an attempt to uncover different aspects of cognitive control related to DLPFC involvement. In sum, rapid and sequential up-regulation of the attentional set seems to be related to the left DLPFC. These attentional adjustments are based on participants’ expectancies regarding the conflicting nature of the upcoming trial, and not on the conflict itself. In contrast, the right DLPFC is associated with an overall up-regulation of the attentional set when attentional conflict is experienced.     

Psychosocial mediators of a lifestyle physical activity intervention in women

ObjectivesA lifestyle physical activity intervention in women based on the transtheoretical model and social–cognitive theory effectively increased physical activity. The aim of the present study was to examine possible mediators (perceived benefits and barriers of physical activity, self-efficacy, processes of change, and social support) of these physical activity changes.MethodsMembers of four units of a women's organization followed a six-month minimal-contact physical activity program. The intervention program included one group meeting, a self-help booklet and five monthly reminder letters. Members of two other units served as control group. Physical activity (accelerometer counts), and psychosocial constructs (self-report questionnaires) were assessed at baseline (pretest) and directly after the intervention (posttest). Women who completed all measurements (n = 101) were included in the mediation analyses.ResultsParticipants in the intervention group reported significantly greater increases in the use of behavioral processes from pretest to posttest than participants in the control group. None of the proposed psychosocial constructs showed a mediating effect on changes in physical activity.ConclusionsThe mechanisms proposed by the transtheoretical model and social–cognitive theory could not explain the positive effect of the intervention on physical activity. Identifying the working components of an intervention remains a challenging and necessary step in the development of effective low-cost and high-reach physical activity interventions.