Extending a class of motion stimuli to study multiattribute texture perception

We present a class of stimuli that makes it possible to study the interaction of visual attributes in forming textural patterns. These stimuli are obtained in a simple manner from a class of motion stimuli that we described earlier (Papathomas & Gorea, 1988). The main advantages of the texture stimuli presented in this paper are: (1) each attribute can be arranged simultaneously with, but independently of, other attributes, (2) an arbitrary number of attributes can be used, (3) the interaction of attributes can be studied systematically, (4) direct comparison of two attributes is possible with stimuli in which the two are arranged to form competing patterns, and (5) because of the similarity to the motion stimuli, the relationship between texture and motion mechanisms can be investigated.     

Performance of humans in concurrent avoidance/positive-reinforcement schedules

Performance maintained under concurrent schedules consisting of a variable-interval avoidance component and a variable-interval positive-reinforcement component was studied in three human subjects using points exchangeable for money as the reinforcer. The rate of responding in the avoidance component increased, and the rate of responding in the positive-reinforcement component declined, as a function of the frequency of point-losses avoided in the avoidance component. The performance of all three subjects conformed to equations proposed by Herrnstein to describe behavior in concurrent schedules. The logarithms of the ratios of the response rates in the two components, and the logarithms of the ratios of the times spent in the two components, were linearly related to the logarithms of the ratios of the frequency of loss avoidance in the avoidance component to the frequency of reinforcement in the positive-reinforcement component. When a changeover delay of 5.0 sec was imposed, the slopes of the linear functions were close to 1.0 in the case of two subjects, whereas the third subject exhibited significant undermatching. For two subjects the changeover delay was then reduced to 2.0 sec; in both cases the slopes of the linear functions were lower than under the 5.0-sec condition. One subject participated in a third phase, in which no changeover delay was imposed; there was a further reduction in the slopes of the linear functions.     

Place information in multidigit number comparison

How do we use place information in a number comparison task involving multidigit numbers? In four experiments, subjects identified stimulus numbers as larger or smaller than the number 5,000 in a choice reaction time task. As the difference between the number of places in the stimulus number and the number of places in the standard decreased, response time and errors significantly increased. When the number of places was held constant, the type of numeric information extracted depended on the value of the standard (5,000 or 5,555). In some cases, irrelevant place information affected choice time.     

Mentally retarded individuals outperform college graduates in judging the nonconservation of space and perimeter

Most adults of average and superior intelligence incorrectly assume that in a two dimensional figure two attributes, area, and perimeter, are locked in a fixed relationship such that if one remains unchanged so does the other. Consequently, when they correctly conserve one attribute during shape transformation, they incorrectly conserve the other. Mentally retarded individuals assume no such fixed relationship but depend exclusively on perceptual information. Although this dependence adversely effects their judgment of conservation, it allows them to correctly judge the changed state of the nonconserved attribute.     

Tower of Hanoi performance of retarded young adults and nonretarded children as a function of solution length and goal state

Three experiments were conducted with the Tower of Hanoi task to assess problem solving ability in 6-, 7-, 8-, and 10-year-old nonretarded children and mentally retarded young adults of varying maturational ages. In Experiment 1 we gradually reduced the number of moves required for solution until subjects could solve the 3-disk tower-ending problem. Although all groups experienced difficulty with the standard 7-move problem, all but the trainable retarded group readily solved the 6-move problem. The trainable group did not reach a comparable level of success until the 4-move problem. On the 7-move problem the retarded groups performed at the level of nonretarded groups that were maturationally $\text{1}\text{1}\text{2}$ to 3 years younger. An analysis of first moves indicated that subject groups differed in the strategies they used to solve the problems. In Experiment 2, practice effects were ruled out as a source of the superior performance on the 6- than on the 7-move problem. In Experiment 3, 7- and 10-year-old nonretarded children and mentally retarded young adults did not differ on 5-move problems in which configuration of the goal states was varied. A comparison of all 5-move problems judged to have the same depth of search requirements indicated that the tower-ending problems were significantly easier to solve than the partial-tower-ending problems, which in turn were easier than the flat-ending problems. A limited depth of search capacity sets boundaries on the use of sophisticated strategies and, to a large extent, accounts for the retarded groups' maturational lag.     

TRUTH IN RELIGION: A POLANYIAN APPRAISAL OF WOLFHART PANNENBERG'S THEOLOGICAL PROGRAM

Abstract. This essay attempts to explore the senses in which religious meanings may be understood to be grounded ontologically and in which they may be validly accepted as true. It begins by outlining Wolfhart Pannenberg's proposal for conceiving the scientific status of theology and his formulation of the question of theological truth. Then certain epistemological presuppositions are challenged in light of Michael Polanyi's theory of knowledge. Finally a revised understanding is proposed in Polanyian terms. Here in their primordial sense religious meanings are based in the act of breaking out toward the ground of our tacit foreknowledge. In their primary sense religious symbolizations are accepted as human creations and judged to be valid insofar as they integrate meaningfully all the disparate elements of our experience.     

The Radio Shack color computer in the experimental psychology laboratory: An evaluation

The Radio Shack color computer is examined from the viewpoint of capabilities needed to program, time, control, and acquire data from typical cognitive psychology experiments. Its capabilities are compared with those of the alternative inexpensive microcomputers discussed in an earlier article (Reed, 1980). The paper also includes a 6809 assembly language routine that permits the measurement of reaction times in video horizontal scan (HS = 4/63 msec) units without hardware modifications and an RSCC BASIC program for unbiased conversion of HS units to milliseconds.     

What children say when asked “What?”: A study of the use of syntactic knowledge

The present study explores two questions: What is the nature of older children's syntactic knowledge; how is that knowledge used in an everyday speech situation? Six-, eight-, and ten-year-olds repeated grammatical sentences as read by the first experimenter. Half the sentences were syntactically clear, half slightly distorted. Clear versions displayed basic grammatical relations and constituent structure perspicuously. The second experimenter, who sat at the other end of the room, asked “What?” after each sentence. The syntactic changes children might make to accommodate the listener were examined. Although the children made a variety of changes, at all ages they tended to change distorted versions to clear ones, and to repeat clear versions. The results suggest that children's syntactic knowledge is deeper and more accessible than had been supposed.