M. Beth Casey

Mediators of Gender Differences in Mathematics College Entrance Test Scores: A Comparison of Spatial Skills with Internalized Beliefs and Anxieties.

This study was designed to investigate whether spatial skill, math anxiety, and math self-confidence functioned as mediators of a significant gender difference in the Mathematics Scholastic Aptitude Test (SAT-M) among the top third of a college-bound sample. Using path analytic techniques, the decomposition of the significant gender-SAT-M correlation into direct and indirect effects indicated that there were no direct effects of gender on SAT-M. Mental rotation and math self-confidence showed indirect effects, mediating the gender-SAT-M relationship; math anxiety did not. Of these indirect effects, 36% was mediated by math self-confidence; 64% by mental rotation. For both these variables, most of the mediational effects of the gender-SAT-M relationship did not occur by way of the causal pathway leading through geometry grades. Thus, the mediational effects cannot simply be attributed to the presence of geometry items on the SAT-M or to math self-confidence acquired during prior geometry coursework.

Exceptions to the male advantage on a spatial task: Family handedness and college major as factors identifying women who excel ☆

Two factors, family handedness and college major, were investigated in order to identify the characteristics of women likely to excel on a mental rotation task. It was found that those likely to have the necessary combination of genetic potential and spatial experiences were right-handed women with nonright-handed relatives, majoring in math-science fields. Across three samples, this subgroup significantly outperformed all other groups of undergraduate women and did as well as undergraduate men on the Vandenberg Mental Rotation Test. This study provides new information on possible genetic and environmental factors influencing mental rotation ability in women.

Spatial ability as a predictor of math achievement: the importance of sex and handedness patterns.

In accordance with major theories of handedness and brain organization, differential predictors for math achievement were found as a function of sex and handedness subgroups among eighth graders. Although there was no difference in absolute levels of performance as a function of either sex or handedness, predictive structures did differ. Regression analyses showed that spatial ability predicts math achievement for: (1) girls with anomalous dominance (non-right-handers and right-handers with non-right-handed relatives), and (2) all boys (independent of handedness group). In contrast, for the standard dominance girls who are right-handed with all right-handed relatives (considered strongly left-hemisphere dominant for language), spatial ability did not predict for math achievement. These findings occurred, even when scholastic aptitude and verbal achievement factors were controlled. It was concluded that further studies of sex differences in math achievement should consider subgroup differences within the sexes, based on handedness patterns.

Girls who use "masculine" problem-solving strategies on a spatial task: proposed genetic and environmental factors.

This study investigated strategy and performance differences between right-handed boys and girls on a mental rotation task. Based on predictions from Casey and Brabecks (1990) theory of sex differences, the study was also designed to identify a target group of right-handed girls with the optimal combination of genetic and environmental factors (high math/science achievers with nonright-handed immediate relatives). They were predicted to show strategies and performance more similar to those of the boys than to those of both the low math/science achieving girls and the high math/science girls with all right-handed immediate relatives (predicted to have the nonoptimal genotype). Strategy preference was measured using selective interference, whereby subjects solved mental rotation items concurrently with either verbal or visual-spatial interference tasks. Group comparisons were made on the amount of decrement in mental rotation performance as a result of the two types of interference tasks. This provided a basis for comparing the groups on the use of visual-spatial or verbal strategies on the mental rotation task. The boys: (1) did not show a significant advantage over the girls on the mental rotation items, but (2) did depend more on visual-spatial strategies than the girls, and (3) depended less on verbal strategies than the girls. The target girls: (1) outperformed the low math/science achieving girls on the mental rotation items and did not show a significant advantage over the other high math/science group, (2) depended more on visual-spatial strategies than both the other two groups of girls, and (3) depended less on verbal strategies than the low math/science girls, while showing no significant difference compared to the nonoptimal high math/science girls. Examining within-group differences, the boys preferred visual-spatial strategies, while the girls in both the nontarget groups preferred verbal ones. However, for the target girls, no within-subject strategy differences were found. The present findings support the theory that, like the boys, the target girls depend more on visual-spatial strategies than do other girls. It is possible that the target girls use a combination of visual-spatial and verbal strategies when solving mental rotation tasks.

Family handedness as a predictor of mental rotation ability among minority girls in a math-science training program

Right-handed girls from nonright-handed families outperformed the other groups of minority adolescent girls enrolled in a science and technology program on a test of mental rotation ability. This target group excelled over right-handed girls with all right-handed relatives and nonright-handers. The pattern of group differences in mental rotation ability found here is consistent with those found for women with math-science training at the college level. The minority boys in the program outperformed the girls as a whole, but did not differ significantly from the right-handed girls with nonright-handed relatives. The present findings provide further support for the generality of Annetts genetic theory of handedness and brain organization, and for the interaction of genetic and environmental factors in accounting for individual differences in mental rotation ability.

Evidence in support of a model that predicts how biological and environmental factors interact to influence spatial skills

It was proposed, based on M. Annett (1985), that individuals biologically predisposed to poorer spatial skills are less likely to capitalize on opportunities to develop these skills. Using an analysis of variance design assessing mental rotation skills in 2 cohorts of 8th graders (365 students), the authors found a significant 3-way interaction (Brothers x Family Handedness x Gender). For the girls with brothers, those from all right-handed families had lower mental rotation scores than did the other girls. For the 2nd cohort, among those children who participated in mental-rotation-type activities with their brothers, both boys and girls from all right-handed families performed more poorly on the mental rotation test than did the other children with brothers. Thus, compared with other children, the children from all right-handed families do not appear to be able to use their spatial experiences with male siblings to increase their spatial skills.

Gender, sex, and cognition: Considering the interrelationship between biological and environmental factors

Abstract In this commentary, the first section will present some of the patterns which seem to be emerging from across the articles in the special issues of Learning and Individual Differences on gender and cognition. Then in the second section I will consider these findings from a biological/ environmental interactionist perspective.

Spatial Abilities and Reading Deficits in Visual Art Students

This study investigated the hypothesis that artists are characterized both by strengths in spatial visualization and problems in reading. In addition, we investigated whether such a profile is most likely to describe nonright-handed artists. A test of spatial visualization ability and a self-report questionnaire assessing reading problems were administered to students majoring in the visual arts. Art students were compared to those majoring in other spatial fields (mathematics and science) and to those majoring in verbal fields that do not call for spatial skill (humanities and social sciences). While both art and mathematics/science students excelled in spatial visualization relative to those in verbal fields, the mathematics/science students outperformed the art students. Nonright-handers did not differ from right-handers in spatial ability. However, it was the nonright-handers among the artists who were most likely to report reading difficulties. Results suggest that individuals choose spatial fields because they possess the relevant spatial visualization abilities; however, nonright-handed individuals with reading difficulties may also go into art in part by default, to avoid fields which require extensive reading and writing.

Differences in feminine and masculine characteristics in women as a function of handedness: Support for the Geschwind/Galaburda theory of brain organization

The Geschwind/Galaburda testosterone theory successfully predicted differences in feminine sex role identification and behavior between women with anomalous dominance and standard dominance. The women with anomalous dominance (consisting of left-handed and ambidextrous as well as right-handed women with first-degree non-right-handed relatives) were compared to women with standard dominance (right-handed women with all right-handed first-degree relatives) on the Bem Test of Sex Role Identity and a tomboy scale. Across three samples, handedness classifications were related to both tomboy characteristics and sex role identification. In addition, the study showed that the anomalous dominance women had a higher masculine sex role identification as compared to the college normative sample for the Bem, while the standard dominance women had a higher feminine identification than the normative sample.

Familial handedness and its relation to spatial ability following strategy instructions

Abstract This study compared subjects from right-handed families with subjects from nonrighthanded families in their ability to solve a mental-rotation task when instructed to use one of two different spatial strategies. All subjects completed a pretest Vandenberg. Next, one of the following procedures was presented prior to administering the Vandenberg posttest: Group 1 was given mental-rotation instructions, Group 2 was given spatial-orientation instructions, and Group 3 (control group) was given no special directions. For familial right-handers, no condition effects were found. In contrast, familial nonright-handers benefited significantly from mental-rotation instructions when compared both to their own control group and to familial right-handed subjects given the same instructions. However, with orientation instructions, the familial nonright-handers showed significantly less posttest improventnt than their control group. These results suggests familial non-rright-handers may be stronger in ability to use one spatial strategy, transformation of mental images, and weaker on a second, reorientation in relation to left-right cues. The educational and research implications of these findings are discussed.