Seeing textons in context

Texton theory holds that visual texture segregation occurs through the preattentive detection of local differences in primitive visual units called “textons.” Three textons have been proposed for shape: lines, line terminators, and line intersections. The experiments reported here show that line closure also behaves like a texton under some conditions. In addition, the experiments show that texture segregation is not determined by texton differences per se, but by the extent to which the unique textons in a region are salient in the context of the textons common to regions. This suggests that preattentive vision is not as simple minded as texton theory claims it to be.     

The electronic chalkboard

The present paper describes “the electronic chalkboard” (TEC), a teaching innovation made possible by the recent development, under a FIPSE grant to CONDUIT, of specialized instructional software. The instructional power of TEC casts the computer in the role of catalyst in the student-teacher dyad and leads to the emergence of the more powerful student-computer-teacher triad. Relevant educational principles and CAI techniques that should ensure the intelligent use of TEC are discussed.     

An empirical investigation of self-esteem as a composite construct

Three measures of chronic self-esteem, plus four measures developed to assess situational components of self-esteem (task-specific self-esteem and social self-esteem), were administered to 238 undergraduates at a large, urban university and a community college in the southeastern United States. Evidence for a composite construct of self-esteem was found. Results also indicate task-specific self-esteem correlates as high as .42 (p < .01) with chronic self-esteem and as high as .76 (p < .01) with social self-esteem. Task-specific self-esteem was found to be a better predictor of grade point average than chronic or social self-esteem. Suggestions are made for further research on the situational components of self-esteem to extend current findings.     

Factors influencing readability of rapidly presented text segments

Experiment 1 compared paragraph comprehension for texts shown either as normal pages on a computer terminal screen or as rapid serial visual presentations (RSVPs) of small text segments to a common location. Over several days of practice, reading comprehension was equivalent in the normal presentation mode and the RSVP format. When successive RSVP segments contained some information in common, to mimic the experience of successive parafoveal and foveal views of words in normal reading, comprehension was somewhat worse than when successive segments contained no overlapping information. Experiment 2 used a variety of segment size and segment duration combinations to investigate the optimal means of presenting text in the RSVP format. Across a variety of presentation rates and text difficulties, comprehension was maximal for segments averaging about 12 character spaces in length. In Experiment 3, texts were divided into short idea units or into random segments of equal average length. Comprehension was shown to be greater in the structured condition than in the random condition. An optimal means of presenting text in the RSVP format could be superior to normal presentation methods for reading and other text-processing tasks.     

A word’s meaning affects the decision in lexical decision

The influence of an isolated word’s meaning on lexical decision reaction time (RT) was demonstrated through four experiments. Subjects in two experiments made lexical decision judgments, those in a third experiment pronounced the words used in the lexical decision task, and those in a fourth experiment quickly pronounced their first associative response to the words. Differences in lexical access time for the words were measured with the pronunciation task, and differences in meaning were assessed with the association task. Multiple regression analyses of lexical decision RT were conducted using associative RT, pronunciation RT, and other target word properties (printed frequency, length, instance dominance, and number of dictionary meanings) as predictor variables. These analyses revealed a relationship between lexical decision RT and associative RT after the effects of other variables had been partialed out. In addition, word frequency continued to have a significant relationship to lexical decision RT beyond that shared with pronunciation RT and the other variables. The results of these experiments indicate that at least some of the effect of word meaning and word frequency in lexical decision is attributable to a decision stage following lexical access.     

Selective attention and rehearsal in the auditory short-term memory task performance of poor and normal readers

The performance of poor and normal sixth-grade readers was compared on an auditory short-term memory task in two studies. In the first study, the effects of distraction, list length, and speed of stimulus presentation were investigated to test the hypothesis that the performance of the poor readers is affected by deficits in selective attention. Group differences in performance, however, were obtained for both distraction and no-distraction conditions. The second experiment examined the hypothesis that group differences may reflect differences in the use of rehearsal. In the second experiment, half the reading-disabled children and half the controls were provided with rehearsal training prior to completing the same short-term memory task a second time. Rehearsal training resulted in improved performance relative to children who were not trained; however, there was no rehearsal training x reading group interaction. The poor readers continued to show deficits in performance relative to the performance of control children. The results of these two studies suggest that deficits observed for poor readers on short-term memory tasks may reflect processing difficulties in some area that precedes rehearsal and affects performance under both distraction and no-distraction conditions.The authors wish to express their thanks to the Sachem School District and Betty Gould, Nicholas Opinanate, and Guy Barber for their unlimited cooperation, and to John Neale for very helpful discussions of a number of issues in this paper.     

Childhood aggression and social adjustment as antecedents of delinquency

A sample of 2,453 grade school children were followed into young adulthood through record sources. Teacher interviews provided information about low-peer-status children that was assessed in relation to subsequent delinquency for both sexes and young adult criminality for males. A multivariate design evaluated the joint effects of social class, a measure of family disturbance, and childhood problem behavior factors as antecedents of delinquency. Childhood aggression emerged as the most prominent antecedent factor for males but not for females. Social class and family disturbance were associated with aggression but did not have significant direct effects on delinquency. Aggression was related to severity of delinquency. Dispositional status, reflecting severity, was the best indicator of which delinquent males would have adult criminal records. A causal model is presented.The study was supported by a grant from the Scottish Rite Schizophrenia Research Program, N.M.J., U.S.A. Portions of the study were presented at the Life History Research conference in Monterey, California, 1981. The authors wish to thank June White, Cindy Hanson, and Ned Worell for their help in conducting this research. Data for this research was originally gathered by Merrill Roff. Follow-up data were contributed by Ronald Peek, Donald Bamber, Charles Watson, Shiela Makie, William S. Ward, Edward S. Posey, Chris Hemlabs, and Harriet Barnes.