title: Dichotic listening and tactual mental rotation in females as a function of familial sinistrality and strength of handedness.
abstract: In this study the effects of familial sinistrality and strength of handedness on dichotic listening and tactual mental rotation were investigated. Nonfamilial left-handers were inferior to familial left-handers, particularly in right-ear performance. The decrement in right-ear performance is interpreted as indicative of a pathologically functioning left hemisphere in nonfamilial left-handers. The direction of ear asymmetry tends to be more predictable in strong left-handers than in weak left-handers, with nonfamilial strong left-handers showing a significant left-ear superiority and familial strong left-handers a nonsignificant right-ear superiority. In the tactual mental rotation task, the results suggest a preference of left-handers for a verbal encoding strategy, especially in the right hemisphere. This preferential strategy is particularly manifest in familial weak left-handers and nonfamilial strong left-handers. The results are discussed in terms of their implications for underlying patterns of cerebral organization in the left-handers.
mesh_terms: D000328:Adult; D001307:Auditory Perception / Q000502:physiology*; D004007:Dichotic Listening Tests; D004292:Dominance, Cerebral; D005260:Female; D007839:Functional Laterality; D005824:Genetics, Behavioral; D006801:Humans; D012399:Rotation; D013028:Space Perception / Q000502:physiology*; D014110:Touch / Q000502:physiology