Temporal Effect on Tactile Letter Recognition by a Tracing Mode

Two experiments examined the temporal effect on tactile letter recognition of sequentially tracing a stimulus in the order of making the necessary strokes. The effect of time interval between letter-strokes was examined in Exp. 1, with the three measures, recognition accuracy, latency, and readability. Accuracy of recognition did not differ by change in time intervals, but latency showed a downward trend, and readability showed an upward trend with an increase in the time interval. The effect of duration of exposure (number of pulses which activates each vibratory stimulator defining a letter) was examined in Exp. II with two measures, accuracy of recognition and latency. Both accuracy of recognition and latency reached optimum with 8 pulses per stimulator. The time interval between letter-strokes contributed strongly at the shorter exposure. The minimum was about 80 msec, for the interval between letter-strokes, and 4 pulses per stimulator considering the practical demands of fast exposure and easy identification.