Finite automata and S−R models

Suppes (1969, Journal of Mathematical Psychology, 6) apparently proved that any finite automaton could be mimicked by the asymptotic behavior of a stimulussampling S?R model, broadly implying that cognitive theory could be reduced to S?R theory. Here it is shown that the finite automata used by Suppes are more restricted and less powerful than finite automata in general. Furthermore, the S?R models proposed by Suppes are limited to producing the behavior of only these restricted automata, and cannot mimic all finite automata. Hence, the formal claim that S?R models are adequate to produce all behaviors obtainable from finite automata, and the informal claim that cognitive theory reduces to S?R theory, do not follow from Suppes's (1969) result. Some alternative S?R models and their problems are also briefly discussed.     

Forest before trees: The precedence of global features in visual perception

The idea that global structuring of a visual scene precedes analysis of local features is suggested, discussed, and tested. In the first two experiments subjects were asked to respond to an auditorily presented name of a letter while looking at a visual stimulus that consisted of a large character (the global level) made out of small characters (the local level). The subjects' auditory discrimination responses were subject to interference only by the global level and not by the local one. In Experiment 3 subjects were presented with large characters made out of small ones, and they had to recognize either just the large characters or just the small ones. Whereas the identity of the small characters had no effect on recognition of the large ones, global cues which conflicted with the local ones did inhibit the responses to the local level. In Experiment 4 subjects were asked to judge whether pairs of simple patterns of geometrical forms which were presented for a brief duration were the same or different. The patterns within a pair could differ either at the global or at the local level. It was found that global differences were detected more often than local differences.     

Development of depth perception mediated by motion parallax in unidimensional projections of rotation in depth.

Motion parallax is a composite of five transformations demonstrated to be effective in adult judgments of rotation direction in polar motion projections of a horizontal row of dots rotating in depth. The effectiveness of these transformations as a function of age was tested by presenting six such motion projections to first graders (age = 6 years), seventh graders (age = 13 years), and college students (age = 19 years). Identical age functions were obtained for judged rotation direction from the four motion projections representing (1) Velocity, corresponding to the traditional definition of motion parallax as differential velocity, (2) Velocity plus differences between ratios of instantaneous displacement to instantaneous acceleration for dots on the near and far sides of the rotation axis ($\text{D}\text{A}$ Difference), (3) Velocity, $\text{D}\text{A}$ Difference, and a gradient across the row of $\text{D}\text{A}$ ratios, and (4) all transformations. First graders, unable to use horizontal transformations, performed at chance on these four projections, while older students made correct judgments. Order, separated from Velocity for the first time, resulted in chance performance at all ages, while Direction, also separated from Velocity for the first time, resulted in veridical judgments in only 4 of 24 college students.     

Sequencing of vocational development stages: Further studies

This paper reports two studies which support the prediction derived from Hershenson's (Journal of Counseling Psychology, 1968, 15, 23–30) life-stage vocational development model that average scores on Self-differentiation (worker self-concept and motivation) would exceed those on Competence (work habits, skills, and interpersonal relations), which in turn would exceed those on Independence (appropriateness and crystallization of vocational goals). The first study involved ratings by project staff on an inner city, socially disadvantaged population, and the second study involved self-ratings by individuals who had changed occupations in midcareer. Findings are consistent with those reported by Hershenson and Langbauer (Journal of Counseling Psychology, 1973, 20, 519–521) on a population of deaf clients.     

Repetition and agreement with opposing arguments: A delayed action effect

If exposure to two arguments supporting opposing conclusions establishes two memory traces that influence attitudes, repetition of one of the arguments should produce a delayed action effect. In a computer-controlled experiment, subjects read a large number of arguments about fictitious brands of consumer products from a T.V. screen. They rated each brand immediately after reading about it and again after spending 10 min reading messages about other brands. In the critical conditions of the experiment, two arguments were presented about each brand. One described a good quality of the product (e.g., excellent durability); the other described a bad quality (e.g., below-average efficiency). Subjects read one of the opposing arguments concerning each brand repeatedly and studied the repeated arguments for memory tests. As predicted, repetition and studying affected ratings on the delayed post-test, but not on the immediate post-test. Specifically, attitudes shifted over the delay toward agreement with the repeated arguments, supporting the idea that the persistence of attitudes depends on more than one memory trace.     

Polarizing effects of social comparison

Does exposure to others' judgments merely elicit conformity to what is observed? Two experiments are reported in which people who were merely exposed to others' responses tended not to conform to the average observed response but to exceed it in the socially preferred direction. These experiments complement social psychology's historic emphasis on conformity by suggesting that not only do people avoid being markedly deviant from others; they also act to differentiate themselves from others toward the extreme that reflects the group ideal.     

Auditory processing and perceptual abilities of “organic” and “functional” stutterers

The present investigation was undertaken to determine whether significant differences in auditory processing and perceptual abilities exist between (1) stutterers as a supposedly homogeneous group when compared with controls, (2) two differentiated subgroups of stutterers, and (3) either of the stuttering subgroups when separately compared with controls. Dichotic listening and masking level difference (MLD) tasks were administered to the two groups of school-age stutterers and an age-matched nonstuttering control group. Stuttering subjects were differentiated into “organic” and “functional” subgroups on the basis of neuropsychological test performances. Organic stutterers performed significantly poorer than did controls on one MLD experimental condition. Functional stutterers performed more like control subjects than like organic stutterers.