Citation

Blouin J, Vercher JL, Gauthier G, Labrousse L, Simoneau M. Vis. Veh. 1999; 7: 329-336.

Copyright

(Copyright © 1999, Elsevier Publishing)

DOI

unavailable

PMID

unavailable

Abstract

To ensure successful interaction with the environment, individuals must constantly update their position with respect to the stationary or moving elements present in their environment. The environment of a driver is composed of an internal proximal space (i.e. the cockpit) and an external more distal space (i.e. the environment in which the vehicle circulates). Processing spatial information is complex because the elements of the cockpit remain stationary with respect to the driver when the vehicle is in motion while the position of external space objects constantly vary.

When the vehicle is in motion, the driver is constantly submitted to labyrinthine stimulation: the otoliths being activated by linear motion of the head and the semicircular canals by angular acceleration. In this experiment, the authors studied subjects' capacity to determine the position of a fixed target after varying head-in-space positions. The subject sat on a chair positioned at the centre of a semi-circular black cylinder. The chair could be rotated by the examiner about the vertical axis. Subjects were instructed to gaze at a straight-ahead target and then to indicate the perceived position of the target after head-trunk rotations. Subjects were found to be able to retrieve the position of the target when their head remained stationary: but when the subjects were rotated during active head rotations, their precision in target position estimation was markedly decreased. Overall, the results suggest that cervical signals are likely to be the source of information that allows accurate coding of target position after head rotations when the trunk remains stationary. The finding highlights the danger that a driver may encounter during non-instrumental navigation in the dark.