Abstract
The relative influence of experience and maturation on the development of left-right directionality was investigated. The subjects were 15 3- and 94-yr.-old black and Puerto Rican children who had failed to use a left-right sequence in counting arrays of checkers. Within each age level approximately equal numbers of girls and boys were assigned to experimental and control groups ( ns = 12). Experimental children were trained to count using the left entry and the rightwards directional movement. Trained girls and boys used significantly more left-right and alternative linear counting strategies on a posttest given three days following training than did untrained children. Trained girls, but not boys, retained the left-right strategy in the second posttest 2 wk. later. The findings suggest that both learning and maturation may influence directionality in perceptual exploration.