did a search on pubmed. seems like there's no clear answer.
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Percept Mot Skills 1989 Jun;68(3 Pt 1):839-46 Related Articles, Books, LinkOut
Mixed-handedness and achievement test scores of grade school children.
Sarma PS.
Department of Psychiatry and Behavioral Sciences, University of Health Sciences, Chicago Medical School, North Chicago, Illinois 60064.
Normal Curve Equivalent Scores on subtests of the California Achievement Test for mixed-handed children, 52 boys and 58 girls from Grades 3 and 4, who are right- and left-handed writers, indicate no differences by handedness in girls, but among the mixed-handed fourth grade boys, those who wrote right-handed scored lower on Study Skills than the boys who wrote left-handed.
PMID: 2748300 [PubMed - indexed for MEDLINE]
Handedness and spatial ability.
Sanders B, Wilson JR, Vandenberg SG.
Data from a large-scale study of cognitive abilities were used to test the hypothesis that there are handedness-related differences in spatial visualization. The spatial factor score of the cognitive test battery provided a measure of spatial visualization. Analyses revealed a sex X handedness X ethnicity interaction on the spatial factor, and no significant handedness-related differences on verbal factor. In all ethnic groups [B} strongly left-handed males had higher spatial scores than strongly right-handed males, whereas strongly left-handed females had lower spatial scores than strongly right-handed females.{/B] Among subjects of Japanese or Chinese ancestry, strongly left-handed subjects differed from ambidextrous subjects as well as from right-handed subjects, and these differences, too, were of opposite sign for males and females. It is suggested that the use of spatial ability measures which are relatively insensitive to differences in right hemisphere ability, as well as the failure to attend to degree of handedness, ethnicity, and particularly gender, may be responsible for the negative findings in this area of research.
PMID: 7187636 [PubMed - indexed for MEDLINE]
Handedness and intelligence.
Hicks RA, Beveridge R.
The scores of 37 right and 30 left-handed subjects on tests of fluid and crystallized intelligence were compared. [B}Consistent with the hypothesis, it was found that the left-handers were inferior to the right-handers on the Gf task. {/B] These data are consistent with those from three earlier studies and serve to question the assertion that there are no handedness related differences in ability.
PMID: 679711 [PubMed - indexed for MEDLINE]
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