Developmental versus sensory deficit effects on perceptual processing in the reading disabled

Thirty children and 5 adults participated in two experiments designed to compare visual processing in normal and reading disabled children. The children were aged 8, 10, and 12 years. In Experiment 1, subjects were asked to detect the temporal order of two briefly presented stimuli. In Experiment 2, subjects sorted cards containing bracket stimuli that did or did not produce perceptual grouping effects. Poor readers required more time to make accurate temporal order judgments and showed stronger perceptual grouping effects. For both good and poor readers, the amount of time necessary to make a correct temporal order judgment decreased, and perceptual grouping effects became weaker with age. However, the magnitude of the difference between the groups did not lessen with age. These results suggest that there are visual processing differences between good and poor readers that do not appear to correct by age 12.     

Using direct and indirect measures to study perception without awareness

Many studies directed at demonstrating perception without awareness have relied on the dissociation paradigm. Although the logic underlying this paradigm is relatively straightforward, definitive results have been elusive in the absence of any general consensus as to what constitutes an adequate measure of awareness. We propose an alternative approach that involves comparisons of the relative sensitivity of comparable direct and indirect indexes of perception. The only assumption required by the proposed approach is that the sensitivity of direct discriminations to relevant conscious information is greater than or equal to the sensitivity of comparable indirect discriminations. The proposed approach is illustrated through an evaluation of Avant and Thieman’s (1985) recent claim that an indirect measure of perception based on judgments of apparent visual duration provides a more sensitive indicator of perception than does a direct measure based on forced-choice recognition. Contrary to this claim, when direct and indirect indexes are measured under comparable conditions, an indirect measure based on judgments of perceived duration provides a less sensitive index of perceptual processing than do comparable direct measures. The proposed approach provides a general conceptual/methodological framework for using the dissociation paradigm in studies directed at establishing unconscious processes.     

The ratio principle holds over a million-to-one range of illumination

Infant sensitivity to kinetic information specifying three-dimensional object shape was assessed using computer-generated random-dot displays. Four-month-old infants were habituated to displays of an object oscillating about two different axes on alternating trials. Following habituation, the infants were tested for recovery from habituation to a display of the same object and a novel object. Both test displays employed a new axis of rotation. The infants generalized habituation to the same object and increased their looking to the new object. These results provide evidence that infants are sensitive to motion-carried information specifying three-dimensional object shape, since the random-dot displays minimized static information that differentiated the two objects. These findings suggest that, at least by 4 months of age, infants can detect subtle differences in shape from purely kinetic information.     

The association between adolescents' attitudes toward suicide and their psychosocial background and suicidal tendencies.

The present study examined the relationship between adolescents' attitudes toward suicide and their psychosocial background. It also evaluated the association between attitudes toward suicide and the subjects' own suicidal tendencies. A questionnaire assessing these issues was administered to 525 Israeli adolescents. Results indicated that significantly more females, nonreligious adolescents, those exposed to suicidal behavior, and those with increased suicidal risk held more accepting attitudes. Ethnic origin, socioeconomic status, and living in intact/nonintact families were not associated with adolescents' attitudes toward suicide.     

Differences in school behavior and achievement between children from intact, reconstituted, and single-parent families.

Differences in school behavior and achievement between students from intact, reconstituted, and single-parent families were analyzed. Students from intact two-parent families had fewer absences and tardies, higher grade point averages, and fewer negative and more positive teacher behavioral ratings than did those from reconstituted and single-parent families.     

Selecting a best multiattribute alternative with partial information about attribute weights

Use of approximate weights would greatly simplify decision analysis under certainty since detailed weight elicitation could be avoided. This paper examines the degree to which rank order information about weights can be used to identify a best alternative, or falling uniqueness prescribes an easily implemented rule for selecting a ‘best’ alternative. The prescribed rule uses as weights the centroid of the feasible region defined by the rank order information. In conjunction with the rule, the value of the rank order information can be determined using an ‘expected gain from weight precision’ (EGWP) measure, analogous to ‘expected value of perfect information’ in decision analysis under uncertainty.     

Risk and behavior: The mediating role of risk appraisal

The main issue of this paper concerns the mediating role of risk appraisal in the relation between past and future behavior. We expected previous risky behavior to heighten risk appraisal, which, in turn, should stimulate preventive behavior. Results ofthree tests of this mediation hypothesis showed that past behavior was strongly related to future behavior; people who behaved hazardously in the past indicated that they tend to do so in the future. Generally, the expected relation between past behavior and risk appraisal was supported. More risky behavior in the past was associated with a heightened risk appraisal. Results also indicate a relation between risk appraisal and future behavior, but in the opposite direction as predicted. Heightened risk appraisal was related to increased levels of risk in future behavior. When predicting future behavior by both risk appraisal and past behavior the effect of risk appraisal on future behavior disappeared, while past behavior remained a strong predictor of future behavior. In a few cases risk appraisal still predicted future behavior when past behavior was controlled for. Unfortunately, these cases showed the opposite relation; i.e., heightened risk appraisal was related to more risky future behavior. Implications of these findings for research on the role of risk appraisal will be discussed.     

Sources of stress and coping responses of high school students.

A series of focus group interviews was used to identify major sources of stress and coping responses of Grade 10 students. Relationships with parents and family, work, and lack of money were found to be important sources of stress. Major coping responses included substance use and diversionary activities. Differences between academic streams (tracks) in sources of stress and coping responses were examined.