Diane McGuinness

Gender differences in response to spatial frequency and stimulus orientation

Male and female subjects with normal or corrected-to-normal visual acuity and less than .25 diopter of corrected astigmatism were asked to make contrast threshold judgments in response to both stationary and drifting grating displays. Results indicate a sex difference in contrast sensitivity as a function of spatial frequency for vertical and oblique orientations.

Lateral asymmetry: Hard or simple-minded?

A letter or a three-dimensional shape was presented in the center of the visual field. Following the off-set of this stimulus either a comparison letter or a three-dimensional shape was flashed briefly in either the right or left visual field. The subjects task was to respond SAME, or DIFFERENT. The stimuli could be in the same plane, rotated in two dimensions (letters) or in three dimensions (three-dimensional shapes). The left visual field presentations (right hemisphere) of same-pair matches for letters only produced faster reaction times and fewer errors. In all other conditions reaction time measures showed no hemisphere effects. By contrast, error score data indicated that the left hemisphere was overwhelmingly more accurate.

Effort and the Control of Attention

is utilized, improved concept attainment results for both good and poor readers. In testing this hypothesis, answers to the following questions were sought: (1) \Vill students who utilize materials organized according to the Frayer model perform s i g n i f i c a n t l y b e t t e r o n a c o n c e p t comprehension test than students who use materials organized according to the textbook approach? (2) Will both good and poor readers perform significantly better? (3) \Vill arrangement of concept examples within both the Frayer model and textbook a p p r o a c h s ignif icant ly improve comprehension? hfaterial arranged by the Frayer model and the textbook approach was ordered according to chronological, topical, and reverse chronological presentations. A test based on the special materials was developed to measure comprehension. Arrangement of concepts (i.e., topical vs. chronological arrangement) within both the Frayer and textbook methods had no effect on comprehension scores. The results, however, indicated that both good and poor readers who utilized material organized according to the Frayer model received significantly higher comprehension scores than did good and poor readers who employed material organized according to the textbook approach.