The role of three-dimensional depth cues in infants' perception of partly occluded objects

Newborn infants were familiarized to a three dimensional display consisting of a rod which moved behind a central occluder, so that only the top and bottom of the rod were visible. The infants' eyes were 38 cm from the rod and the occluder was 15 cm in front of the rod, a separation intended to ensure that the gap between the two was detected by the infants. On subsequent test trials the infants looked longer at a complete rod than at two rod pieces, suggesting that the hidden unity, or completeness of the rod had not been perceived. In a study by Johnson and Náñez (in press), using computer. generated stimuli, 4 month olds perceived the hidden unity of a similar display presented on a VDU in the complete absence of three. dimensional depth cues. Taken together, these findings suggest that, for these displays, perception of three. dimensional depth cues is not necessary for the detection of the unity of partially hidden objects. It is suggested that age changes in early infancy in the perception of occluded objects may result either from the emergence of abilities to perceive objects from kinematic information or from the emergence of sensitivity to that information itself.     

Verbal and nonverbal maternal controls in hearing mother-deaf child interaction

Investigators of mother-child relations have concluded that mothers of deaf children are more controlling than mothers of hearing children. Excessive maternal control has been linked to inoptimal developmental outcomes, such as child dependence, social immaturity, and submissiveness. In the present study, the verbal and nonverbal controls employed by mothers of deaf preschoolers (3.00–6.75 years) versus mothers of hearing preschoolers (3.00–6.42 years) were evaluated. Subjects were 14 hearing mother-deaf child dyads and 14 hearing mother-hearing child dyads. Each dyad was observed during a 15-minute free-play period and during a 7-minute teaching period. Dependent measures were submitted to appropriate 2 (hearing status) by 2 (task) analysis of variance for repeated measures, followed by post hoc comparisons. The results indicated that the mothers of deaf children: (a) used higher rates of nonverbal controls than the mothers of hearing children, especially during the free-play period; and (b) employed higher rates of verbal controls than the mothers of hearing children during the free-play period, but not during the teaching period. In addition, the interaction tasks exerted differential effects on the two groups of mother-child dyads.     

Examining the reliability and validity of an adapted scale of educational-vocational undecidedness in a sample of graduate students

The present study was an attempt to determine the reliability and validity of an adapted vocational indecision scale designed for undergraduates (Osipow, S. H., Carney, C. G., Winer, J. L., Yanico, B. J., & Koschir, M., In Journal of Vocational Behavior, 1976, 9, 237) for use in a graduate student population. Internal consistency, test-retest, interrater reliability, and validity coefficients were calculated. A factor analysis and a multiple regression were also conducted. The findings suggest that the characteristics of the adapted indecision scale for the graduate students sample are similar to the characteristics of the unadapted instrument for the undergraduate sample in the S. H. Osipow, C. G. Carney, and A. Barak (Journal of Vocational Behavior, 1976, 9, 223–243) study. Potential therapeutic and research uses of the adapted indecision scale are also discussed.     

Auditory-visual conflicts in the perceived duration of lights, tones and gaps

The perceived duration of a short tone (1,000 or 1,500 msec) was longer than that of a separately presented light of equal length. Thus, when light and tone were presented simultaneously, there was a conflict in perceived duration. In that case, the perceived duration of an interval filled with both light and tone was close to that of an interval filled with tone alone. A silent gap in otherwise continuous tone was perceived as longer than a gap in otherwise continuous light, and the perceived duration of a gap occurring simultaneously in both light and tone was close to that of a gap in tone alone. Thus, auditory dominance occurred under the preceding conditions-that is, auditory-visual conflicts in perceived duration, whether occurring between filled intervals or gaps, were resolved in favor of the auditory modality. Visual dominance occurred only under one condition, in which the intensity of tone was reduced, and in which the perceived duration of a 500-msec light was longer than that of a 500-msec tone. The finding of auditory dominance in the perception of time runs counter to the results of studies of sensory conflicts in spatial perception, where vision typically dominates audition and touch.     

Differential effects of fixed- and variable-time feedback on production rates of elementary school children

The performance of 26 third-grade students who worked on individual weekly academic tasks was compared under fixed- and variable-time "home reports". During fixed-time home reports, each student was given a report to take home on Friday that indicated the quantity of work the student had completed that week, contained comments concerning the quality of the work, and had a space for parental remarks and signature. The same report was given during the variable-time reports, except that seven to nine students were randomly selected each day to receive a home report. During variable-time reporting, students completed more assignments and completed assignments on a greater percentage of available workdays than during fixed-time reporting. The teachers' preference for the variable-time reporting was one additional advantage for the variable system.     

Neurodynamics: A critical survey

Following a brief introduction to the functional complexity of an individual nerve cell, the current status of neural network dynamics is reviewed. This survey is then used as a basis for suggesting some fundamental difficulties in developing a science of the human mind.     

The Landslide Victory That Wasn't: The Bias Toward Consistency in Recall of Election Support1

Experiments that test for the judgmental bias that results from a preference for cognitive consistency often contain two threats to their internal validity. First, the subjects are asked to make judgments about themselves. Thus, the biases that result may be explained in terms of cognitive consistency or the motivation to see oneself in a positive light. Second, the decision subjects are asked to make is often difficult to verify objectively. The present research sought evidence in support of cognitive consistency using a methodology that avoided these two confounds. The context chosen was the tendency of perceivers to use the outcome of a group decision to make inferences about the magnitude of group members’ support for the outcome. The present experiment examined whether people in Richmond, Virginia, would use the outcome of a gubernatorial election to make decisions regarding the percentage of people in favor of the winning candidate. Although the winner won by less than one-half of one percent of the popular vote, we found that the subjects significantly overestimated the degree of voter support he received and underestimated the degree of support his opponent received. Moreover, this tendency was exacerbated over time.