As ships have larger mass and tend to suffer disturbance forces of wind, wave and so on, they are regarded as "time lag system" from the point of view of human operation. The purpose of this study is to investigate man's learning process through fundamental experiments and to make clear how a man makes progress to make adaptation to such a time lag system. The experiment was carried out under control of the amount of time lag on cursor motion on CRT through PC. On each trial the participants made responses by press key to stop cursor motion at the location of the small red circle (target) on CRT. The distance between the target and the cursor was dependent variable of this experiment. The participants were divided into two groups at random under either condition of fast or slow cursor speed. The participants of each group made 400 trials which include 2 x 2 conditions of time lag (either small or large time lag from key press to response of PC and either good or bad brake efficiency). The participants made more exact responses under short time lag than long time lag. The most difficult situation was the case that involved three conditions simultaneously (slow cursor speed, large time lag and bad brake efficiency). In this condition, the participants needed more than 90 trials to arrive at the level of accuracy in the other condition. This research provided the evidence that large time lag such as ship motion was more difficult to receive adaptation. We continue to investigate process of learning on time lag in detail.
