Verbal and Spatial Loading Effects on Eye Movements in Driving Simulators: A Comparison to Real World Driving

Abstract

Driving simulators and eye tracking technology are increasingly being used to evaluate advanced telematics. Many such evaluations are easily generalizable only if drivers' scanning in the virtual environment is similar to their scanning behavior in real world environments. In this study we developed a virtual driving environment designed to replicate the environmental conditions of a previous, real world experiment (Recarte & Nunes, 2000). Our motive was to compare the data collected under three different cognitive loading conditions in an advanced, fixed-base driving simulator with that collected in the real world. In the study that we report, a head mounted eye tracker recorded eye movement data while participants drove the virtual highway in half-mile segments. There were three loading conditions: no loading, verbal loading and spatial loading. Each of the 24 subjects drove in all three conditions. We found that the patterns that characterized eye movement data collected in the simulator were virtually identical to those that characterized eye movement data collected in the real world. In particular, the number of speedometer checks and the functional field of view significantly decreased in the verbal conditions, with even greater effects for the spatial loading conditions.