Psychomotor Performance of Input Device Users and Optimized Cursor Control

Abstract

This study examined the fit of the stochastic optimized submovement model (= SOS model; Meyer, Abrams, Kornblum, Wright and Smith, 1988) for cursor movements of two laptop input devices. 10 experienced users of touchpad (easy sensorimotor transformation) and 10 experts for the trackpoint (difficult sensorimotor transformation) executed clicking tasks. Given a model fit, the aim of the study was to discuss the well-known performance inferiority of input devices with difficult sensori-motor transformations on the basis of the SOS model. Cursor movements of both, touchpad and trackpoint, showed a basic fit with the SOS model. With the touchpad, the cursor was easier to control, resulting in a good performance: fewer submovements were carried out from the start to the target, and cursor velocity and acceleration were comparably low. Contrary, with the trackpoint cursor control was more difficult, accompanied by more submovements and a high inaccurateness in the target area: thus, even for experts, the difficult sensorimotor transformation of the trackpoint interfered with a proper motor execution. Actual and potential applications of this research include an optimization of cursor control for input devices and guidelines for their users.