Interactions between area and numerosity

Summary The concept of filled area, i.e. the impressionistic ensemble of parts of a stimulus field occupied by dots, is used to account for various kinds of numerosity illusions due to perceptual interaction between a number of dots and their spatial arrangement. A measure of filled area is derived from a model for the perceptual clustering of dots on the basis of relative proximity. It is shown that the quantified concept of filled area successfully predicts illusion data from earlier studies. Subsequently, a two-alternatives forced-choice numerosity experiment is reported, the data of which gave further evidence of the predictive power of the filled-area hypothesis. Our approach is discussed with respect to spatial features of dot stimuli that might be in rivalry with the filled-area factor in numerosity-estimation tasks.     

From Monroe to Moreau: an analysis of face naming errors.

Functional models of face recognition and speech production have developed separately. However, naming a familiar face is, of course, an act of speech production. In this paper we propose a revision of Bruce and Young's (1986) model of face processing, which incorporates two features of Levelt's (1989) model of speech production. In particular, the proposed model includes two stages of lexical access for names and monitoring of face naming based on a "perceptual loop". Two predictions were derived from the perceptual loop hypothesis of speech monitoring: (1) naming errors in which a (correct) rare surname is erroneously replaced by a common surname should occur more frequently than the reverse substitution (the error asymmetry effect); (2) naming errors in which a common surname is articulated are more likely to be repaired than errors which result in articulation of a rare surname (the error-repairing effect). Both predictions were supported by an analysis of face naming errors in a laboratory face naming task. In a further experiment we considered the possibility that the effects of surname frequency observed in face naming errors could be explained by the frequency sensitivity of lexical access in speech production. However, no effect of the frequency of the surname of the faces used in the previous experiment was found on face naming latencies. Therefore, it is concluded that the perceptual loop hypothesis provides the more parsimonious account of the entire pattern of the results.     

The correlation between coping with stress and blood pressure reaction]

This study explored the relationship between individual strategies of coping and blood pressure responses during and after mental stress. Blood pressure behavior was measured noninvasively and continuously before, during and after a mental stress situation in 27 normotensive subjects. Coping strategies were assessed with the Stressverarbeitungsfragebogen (SVF; coping with stress inventory). Two extreme groups were formed on the basis of the scores in the SVF. Results were: (a) Individuals who used coping strategies characterized by controlling the situation directly and constructively, in contrast to probands not using these strategies, exhibited lower blood pressure during the stress situation and a faster return to baseline levels after cessation of stress. (b) Subjects using a coping behavior characterized by the use of defense mechanisms such as suppression and denial, also showed lower blood pressure during stress but a significantly delayed return to baseline levels of blood pressure after stress was concluded.     

Radikaler Konstruktivismus und Konstruktionismus

Both radical constructivism and constructionism are naturalized approaches to epistemology. They try to fertilize results from biology and psychology for epistemological aims. They both refuse epistemological realism as unsustainable metaphysics. This raises the problem of the range of the naturalistic approach to epistemology. Constructivism, in both forms, turns out to be untenable because it runs in an aporia: it must borrow from realism either, or it must qualify its own position as a metaphysical one. But therewith, constructivism would be blamed to be metaphysical itself.     

Visually controlled matching of pattern movement

Utrecht Biophysics Research Institute, Rijksuniversiteit Utrecht, Utrecht, The Netherlands Subjects were asked to match the speeds of two moving random-dot patterns seen through circular apertures. The speed of one pattern that moved horizontally toward the right of a computer screen changed continuously. The speed of this pattern represented the target. It was to be matched with the speed of the second pattern, which moved in the opposite direction. The subject controlled the speed of the second pattern by means of an isometric joystick. The distance between the apertures on the screen as well as the subject’s distance from the screen served as experimental parameters. In this way, the effects of both spatialand temporal transients of pattern speed on human tracking performance were studied. To avoid anticipation by the subject, the amplitude and the frequency of the target pattern speed changed pseudorandomly. The accuracy with which the subject performed the matching task was influenced by the mean pattern speed and the parameters of the visual field. Within lower velocity ranges, the subject’s sensitivity to the instantaneous speed differences varied according to Weber’s law. The cross-correlation of the velocity time courses decreased when the mean speed of the target pattern was increased. Two stimulus parameters had a strong influence on the modulation of the correlation value: (1) the angular size of the stimulus on the retina and (2) the retinal eccentricity of the stimulus.     

Initial experiences with cognitive therapy of schizophrenic patients

Based on earlier experiences of various groups of authors, we developed and modified a programme of cognitive therapy for schizophrenic patients. The aim of the application of the therapeutic programme to subacute patients was to decrease subjectively perceptible basic disorders and to improve the functions of performance. The present results and experiences with 4 groups consisting of a total of 31 patients encourage us to continue applying cognitive procedures of therapy. Problems of the ascertainment of measuring values and fundamental questions of therapeutic efficacy are discussed.