Measuring Memory and Attention to Preview in Motion

Drivers' Spatio-Temporal Attentional Distributions Are Influenced by Vehicle Dynamics and Displayed Point of View

OBJECTIVE

The aim of this study is to measure drivers' attention to preview and their velocity and acceleration tracking error to evaluate two- and three-dimensional displays for following a winding roadway.

BACKGROUND

Display perturbation techniques and Fourier analysis of steering movements can be used to infer drivers' spatio-temporal distribution of attention to preview. Fourier analysis of tracking error time histories provides measures of position, velocity, and acceleration error.

METHOD

Participants tracked a winding roadway with 1 s of preview in low-fidelity driving simulations. Position and rate-aided vehicle dynamics were paired with top-down and windshield displays of the roadway.

RESULTS

For both vehicle dynamics, tracking was smoother with the windshield display. This display emphasizes nearer preview positions and has a closer correspondence to the control-theoretic optimal attentional distributions for these tasks than the top-down display. This correspondence is interpreted as a form of stimulus-response compatibility. The position error and attentional signal-to-noise ratios did not differ between the two displays with position control, but with more complex rate-aided control much higher position error and much lower attentional signal-to-noise ratios occurred with the top-down display.

CONCLUSION

Display-driven influences on the distribution of attention may facilitate tracking with preview when they are similar to optimal attentional distributions derived from control theory.

APPLICATION

Display perturbation techniques can be used to assess spatially distributed attention to evaluate displays and secondary tasks in the context of driving. This methodology can supplement eye movement measurements to determine what information is guiding drivers' actions.

Spatio-Temporal Flexibility of Attention Inferred from Drivers' Steering Movements

Participants attempted to center a cursor on a video display of a winding roadway with a rate control system. Fourier analysis of their steering movements in response to sinusoidal perturbations of the roadway revealed how much attention they allocated to different roadway preview locations. We compared a full 1.0 s of preview with preview restricted to a narrow slit around 0.3 s or 0.6 s. Participants were able to flexibly shift their attention to either slit. However, they performed better in terms of root-mean-squared error, velocity error, and acceleration error with the fuller view. They concentrated their attention over a range from 0.1 s to 0.3 s of preview in a manner qualitatively consistent with Miller's optimal control model.