Over De Ontwikkeling Van Motorische Voorwaarden Voor Het Schrijven

Abstract

An experiment is reported in which writing and drawing tasks of two different types are presented to 26 subjects in four different age groups. These types of task are supposed to represent 'pure-motor' writing and drawing, requiring very little perceptual and higher control on the one hand, and 'cognitive' writing and drawing, requiring considerable perceptual control without allowing automation or lower-level control to take over, on the other. The tasks were performed both with the left hand and with the right. The variable into which the present paper looks specifically is the preferred direction followed in the production of curves, loops and contours. On the basis of discrepancies between data in the literature and earlier findings by the present authors, it was expected that the two types of task might reveal different motor systems, each displaying its own development with age. This expectation was confirmed. Writing tasks of the 'cognitive' type in general replicated the findings reported in the literature, viz., an increasing preference from the age of 5 or 6 for the counter-clockwise production of curves, loops and contours in copying or drawing single symbols and geometric figures. This preference appears to be independent of the writing hand. Writing tasks of the 'pure-motor' type, however, show a hand-dependent preference, which seems te develop for the left hand from a clockwise to a counterclockwise preference, and for the right hand from a counterclockwise to a clockwise writing bias. The latter appears in continuously drawing circles at maximum speed and in rapid continued scribbling, especially in the youngest (4;5) and oldest (adults) age groups. The feasibility and the possible role of the two independent motor systems, hypothesized to describe the results, are briefly mentioned.