Abstract
We studied the microdynamics of pointing accuracy through pen acceleration. Using a pen equipped with a three-dimensional (3D) accelerometer, healthy volunteers pointed to a self-estimated center, at which two oppositely oblique rectangles (each was displayed for 2 sec) intersected at quasi-random intervals (0, 0.5, 2, and 4s), and an unfixed area within a white background on a tablet-PC display. The standard deviation of the pointing distances from the exact center increased in proportion to the intersection interval. In a typical example, the microdynamics of the gripped pen decreased at powers <10 and 40-100 Hz for the last 3 s at an intersection interval of 4 s. We report the relationship between the microdynamics and the pointing accuracy (prediction deviation) for each intersection interval. [J Physiol Sci. 2008;58 Suppl:S150]
