Influence of six types of visual structure on complexity judgments in children and adults

Individuals at five grade levels (kindergarten, Grade 2, Grade 4, Grade 6, and college) made pair-comparison judgments of visual complexity. The influence of the presence or absence of six types of visual structure (double symmetry, vertical symmetry, horizontal symmetry, diagonal symmetry, checkerboard organization, and rotational organization) and of amount of contour were examined. Two general developmental trends were revealed: First, the age at which visual structure initially affected complexity judgments varied with the type of structure, independent of amount of contour, within the range of contour values used. Second, there was a uniform increase in the effect of structure on complexity judgments between the fourth and sixth grades. These results are discussed in relation to possible mechanisms of visual pattern encoding and complexity judgment.     

Interaction of stimulus size and retinal eccentricity in metacontrast masking

Metacontrast masking occurs both at the fovea and in the retinal periphery; foveally, the smallest stimulus elicited the strongest masking, whereas peripherally the reverse was the case. An analysis of variance showed a significant size effect, eccentricity effect, and size-eccentricity interaction. As stimulus size increased, the stimulus onset asynchrony of maximum masking shifted to greater values. Both foveal metacontrast and peak shifts contradicted predictions made by the hypothesis that metacontrast is mediated by an interaction of sustained and transient channels in the visual system. The data are consistent, however, with a lateral inhibitory model of metacontrast masking and stimulus coding.     

Working with families: a psychoanalytic approach. Thoughts on the Conference Workshop

An account of the work done before, during and after the Workshop meetings is given, with emphasis on the method of working with clinical material through a psychoanalytical framework. Some of the leaders' concerns about using an experiential approach in teaching/learning groups are discussed.     

Components of the reaction time stroop-task

Summary The Stroop-phenomenon in its single-trial reaction-time version is analyzed in terms of Donders's additive-components approach. The complete set of component tasks forms an incomplete factorial design, and so, for resolving reaction times into their component parts multiple regression with dummy coding is used. The results of two independent experiments confirm the asymmetry of the incongruence effect in naming and reading, but contradict the redundancy hypothesis for congruent items. This finding is consistent with the linear approach which in Exp. 1 accounts for about 45%, and in Exp. 2 for about 30%, of total reaction-time variance. In a third experiment reaction times for the detection of colours/words and for congruence/incongruence are measured. These data confirm the estimation of both the basic constant and the assumed matching component in the first two experiments. Finally it is proposed that the data can be interpreted on the assumption that a matching process is responsible for the incongruence effect in naming. Reading interference does not normally occur because of faster processes or fewer stages in a parallel reading channel. Different strategies in coping with the Strooptask (reading vs inhibition) may explain differences between Exps. 1 and 2 and the absence of the redundancy effect from the data. The constraints on such assumptions in the context of reaction-time measurement are discussed.Parts of the data analyzed here were reported at the 18th Congress of Experimental Psychology in April 1976 at Bochum. K.P. Muthig, now at the Free University of Berlin, Dpt. 12, helped in the performance and analysis of the first and third experiments.I gratefully acknowledge the helpful comments of O. Neumann (Bochum) and of three anonymous reviewers of an earlier version of this paper.     

Visual-geometric illusions: unisex phenomena

The possibility of sex differences in responses to visual-geometric illusions was investigated with the use of forty-five illusion variants and a sample of 221 observers. No difference in illusion magnitude as a function of sex was found. A second experiment measured illusion decrement and transfer of decrement to other illusion configurations. Again there were no significant differences between male and female observers.     

Taking Counseling to Minority Students: The Classroom As Delivery Vehicle

This article discusses an alternate treatment approach for helping minority students learn a variety of academic and coping skills. A Special Services course was designed and taught by two counseling psychologists, who were assisted by peer counselors and graduate student group leaders. The goals of this course were to help students develop a more positive set of self-evaluations and to increase individual responsibility and group cooperation among the students. Specifics of the course are presented, and evaluation methods are suggested. In addition, there are implications of this course for minority student retention.     

Instrumental cardiovascular conditioning: A review

This paper reviews experiments, hypotheses, and current controversies about instrumental cardiovascular conditioning. Demonstrations of such conditioning in curarized animals challenged a differentiation between instrumental and classical learning on the basis of their respective effector systems but did not prove direct operant learning by the autonomic nervous system. In humans, ethical prohibition of curarization and lack of adequate controls for respiration and muscle tension have resulted in incomplete understanding of the roles of voluntary, somatic mediators. Despite a variety of potential clinical applications of biofeedback, the available literature lacks studies of its efficacy compared to more standard modes of therapy. The physiological mechanisms and central neural pathways involved ininstrumental cardiovascular conditioning remainalmost totally unknown.     

Effects of a token reinforcement system on journal reshelving

A token reinforcement program involving two levels of token value and backup reinforcers to increase journal reshelving behavior in a large university library was experimentally evaluated. Results showed that instructions (in which signs asked users to reshelve journals) had no impact. By contrast, token reinforcement contingent on reshelving behavior led to a marked increase in journals reshelved. A return to instructions-only conditions, when data were corrected for library usage, showed an increase in unreshelved journals over the token reinforcement period, though the increase was not to baseline levels. For the next 11 months, library staff maintained a modified token program. Follow-up data collected after that interval showed that number of unreshelved journals remained markedly lower than levels at baseline and the first instructions-only period, though they were slightly higher than at the token reinforcement period. Token reinforcement of the variety employed in this study constitutes an efficient, economical means of changing the behavior of library users who fail to reshelve books and journals.