Estimating Information Processing of Human Fast Continuous Tapping from Trajectories

Abstract

Fitts studied the problem of information capacity and transfer in the speed–accuracy motor paradigm using a theoretical approach developed from Shannon and Weaver’s information theory. The information processing (bit/s) estimated in Fitts’ study is calculated from the movement time required to achieve the required task index of difficulty but is essentially different from Shannon’s information entropy. Thus, we estimated the information entropy of multiple human movement trajectories and the mutual information among trajectories for the continuous aiming task in Fitts’ paradigm. Further, we estimated the information processing moment by moment. Two methods were considered: (1) encoded values encompassing the coordinates of the three dimensions and (2) coordinate values associated with each direction in the three dimensions. Information entropy indicates the magnitude of variation at each time point, and the structure of this variation varies with the index of difficulty. The ratio of entropy to mutual information was examined, and it was found that information was processed from the first half of the trajectory in difficult tasks. In addition, since these values calculated from the encoded method were higher than those from the conventional method, this method may be able to estimate these values successfully.

Human Information Processing of the Speed of Various Movements Estimated Based on Trajectory Change

“…Following previous studies [ 12 , 14 , 16 ], we alternately used time-series coordinate data for the x -axis of the pen tip to compute the time difference between the peak (tap to the right-side target) and valley (tap to the left-side target) values. Specifically, the time difference was obtained for the number of taps.…”

“…Furthermore, both were smoothed using a 4th-order bidirectional Butterworth filter (5 Hz low pass filter). Based on previous studies [ 13 , 14 , 17 ], the highest velocity was expected to be approximately at the midpoint of the trajectory for each tap. The extremes of the velocity (positive values: movement from left to the right target, negative values: movement from right to left target) were calculated in absolute values at each movement for each trial to determine the average maximum velocity under each condition.…”

“…Several studies have focused on the variations in trajectories during motion [ 11 , 12 ]. In particular, our previous studies [ 13 , 14 ] focused on the trajectory variation process of motion during Fitts’ experiments. This is an extension of our previous studies, which focused on endpoint fluctuations of trajectories, quantified them, and examined information processing using an approach that focused on periodic fluctuations of movements.…”

“…Several problems exist regarding examining the differences in IDs, such as the ones described above and determining which information processing is appropriate for each control style (feedforward and feedback). The study by Murakami and Yamada [ 14 ] did not consider this issue in depth. To further examine the characteristics of information processing associated with the speed of movement, it is necessary to control the speed of movement externally, as in Woodworth’s experiment.…”

“…Therefore, it was first necessary to examine each participant’s characteristics individually. Thus, as a first step before examining the generality of the relationship between speed and information processing from the data of many participants, we used a previous method [ 14 ], which examined several trials by a single participant.…”