Distractor Interference in Selective Reaching: Dissociating Distance and Grouping Effects

In the present experiment, the authors sought to differentiate between a distance and a grouping explanation for the symmetric versus asymmetric patterns of distractor interference in selective reaching. Participants (N = 16) pointed to a green target that appeared either with or without a red distractor. Target-distractor separation was manipulated within an array of 5 closely grouped stimulus boxes, and distractor interference (difference in performance between trials with and trials without a distractor) was measured in reaction time, movement time, percentage errors, and movement endpoints. Small distances (5 mm) between target and distractor yielded a symmetric pattern of interference, whereas large distances (20 mm) yielded an asymmetric pattern, with more interference from near than from far distractors. Those findings support the distance account of distractor interference and refute the grouping account.     

Design research programs and the logic of their development

Design research programs attempt to bring together the properties of available materials and the demands derived from intended applications. The logic of problem states and state transitions in such programs, including assessment criteria and heuristic principles, is described in settheoretic terms, starting with a naive model comprising an intended profile and the operational profile of a prototype. In a first concretization the useful distinction between structural and functional properties is built into the model. In two further concretizations the inclusion of potential applications is motivated and described for the case of drug research as well as the inclusion of potential realizations for the case of complex products. Next, another line of concretization of the naive model, the incorporation of potentially relevant properties, is sketched. Then the partial analogy between product- and truth-approximation is indicated. We conclude with some remarks about the usefulness of our models for products reaching the market in comparison to the the so-called social construction of technology approach.     

Cognitive modification versus prolonged exposure in vivo: a comparison with agoraphobics as subjects.

Cognitive restructuring and prolonged exposure in vivo were compared in a cross-over design with 21 agoraphobics.Assessments were made at the beginning of treatment, at cross-over, at the end of treatment and at the follow-up one month later. Assessment were carried out by an independent observer (phobic anxiety and avoidance scales and anxious mood) and by the client (measurement in vivo, phobic anxiety and avoidance scales. FSS, ASES, SDS and 1-E scale). Prolonged exposure in vivo proved to be a definitely superior form of treatment to cognitive restructuring, as measured by the behavioral in vivo measurement and the phobic anxiety and avoidance scales.