Unimanual Performance as a Measure of Laterality

The study of unimanual performance as a measure of laterality has ranged from simple concepts such as tests of handedness to highly complex conceptualizations interrelating anthropologic, cultural, genetic, and neurological aspects, including difference between unimanual performance in brain injured versus normal samples. This paper traces measures of unimanual performance through behavioral correlates of natural and unnatural sinistrality as related to cerebral organization, and concludes that unimanual performance represents a robust phenomenon with implications for understanding of neuropsychological correlates of behavior.     

A NOTE ON TRANSFER OF STIMULUS CONTROL IN THE DELAYED-CUE PROCEDURE: FACILITATION BY AN OVERT DIFFERENTIAL RESPONSE

This case study describes initially unsuccessful attempts to use the delayed-cue procedure to teach conditional discriminations to an individual with moderate mental retardation. The task was matching printed-word comparison stimuli to dictated-name sample stimuli. In three experiments, the subject typically waited for the delayed cue unless differential responses to the dictated samples (repeating the sample names) were required. Hence, the study provides an example of a way to make the delayed-cue method more effective. The stimulus control bases for the results are discussed.     

An evaluation of differential prediction of WIAT achievement scores from WISC-III FSIQ across ethnic and gender groups

This study examines differential prediction of WIAT achievement scores based on WISC-III FSIQ in white as compared with African American and Hispanic children, and in females as compared with males. A procedure which allows simultaneous comparisons of slopes and intercepts across groups is employed. The results are consistent with previous research findings in supporting the general absence of bias in predicting achievement from IQ.     

The content of mother stereotypes

Although there is considerable empirical support for the existence of social stereotypes about different types of mothers, the content of those stereotypes is less clear. The purpose of this study was to identify the content of stereotypes related to different types of mothers. Stereotyped attributes of married mothers, stepmothers, divorced mothers, and never married mothers were generated by several samples and combined into one list. A subsequent sample was asked to indicate the percentage of each type of mother possessing each characteristic. The content of mother stereotypes was examined, and the results discussed in light of effects on social interactions, the self-image of women, and future attempts to assess family-related stereotypes.     

Shape discriminations of three-dimensional objects depend on the number and location of bends

In three experiments, subjects made shape discriminations of three-dimensional objects differing in orientation, number of bends, and location of bends (e.g., the central arm vs. a minor subarm). In general, encoding times at 0° disparity on bothsame anddifferent trials were affected by the number of bends, but only after a certain threshold of bends in the objects had been reached (Experiment 1). This effect was not due to the subjects’ having to search for matching ends of the objects (Experiment 2). In contrast, rotation rates were influenced by the location of the bends, but not by the number of bends per se (Experiment 3). The results support a representational scheme that is hierarchical, but not necessarily one in which the principal axis of an object is paramount.     

Text-contingent color aftereffects: A reexamination

Five experiments reexamined color aftereffects contingent on the semantic properties of text (Allan, Siegel, Collins, & MacQueen, 1989). The influence of different assessment techniques and the effect of eye movements and overlapping contour information on the induction of color aftereffects by word and nonword letter strings were determined. Experiment 1 showed that no aftereffect was found when a traditional method of assessing color aftereffects was used. Experiments 2 and 4 demonstrated color aftereffects forboth words and nonwords, but only when subjects fixated the same locus during induction and testing and only when assessed with the technique described by Allan et al. (1989). If, however, eye movements were made during induction, no color aftereffect was obtained (Experiment 3). Induction to nontext patterns with properties similar to those of text but with fewer overlapping contours resulted in a strong color aftereffect (Experiment 5). These results suggest that the color aftereffect contingent on text is very weak and is not dependent on semantic factors, but that it is a product of induction to local color and orientation information.