Hand and hemispace effects in tactual tasks in children.

In Experiment I, 3-and 5-yr-old dextrals matched textures better by either hand when it operated in left hemispace. Girls and 3-yr olds were the more disadvantaged by non-alignment of hand and hemispace. In Experiment II, 8-yr-olds reproduced finger sequences; dextrals demonstrated a right-hand and sinistrals a right-hemispace superiority. In Experiment III, both a left-hand and a left-hemispace superiority appeared when 5-yr-old dextrals reproduced a static configuration of finger spacing. Asymmetries were generally stronger for the side of presentation than for the side of response. Our findings are consistent with the operation of two semi-independent systems, one involving hand-hemisphere connections, and the other mapping of extracorporeal space by the hemispheres.