1. ¹Institute for Biophysical and Clinical Research into Human Movement (IRM), Manchester Metropolitan University, Cheshire, UK
2. ²Department of Physiology, School of Medical Sciences, University of Bristol, University Walk, Bristol, UK

Correspondence: Dr DE Marple-Horvat, Institute for Biophysical and Clinical Research into Human Movement (IRM), Manchester Metropolitan University, Hassall Road, Alsager, Cheshire ST7 2HL, UK. Tel: +44 161 247 5535; Fax: +44 161 247 6375; E-mail: D.E.Marple-Horvat@mmu.ac.uk

Received 20 April 2006; Revised 3 April 2007; Accepted 16 April 2007; Published online 16 May 2007.

Abstract

Driving is a classic example of visually guided behavior in which the eyes move before some other action. When approaching a bend in the road, a driver looks across to the inside of the curve before turning the steering wheel. Eye and steering movements are tightly linked, with the eyes leading, which allows the parts of the brain that move the eyes to assist the parts of the brain that control the hands on the wheel. We show here that this optimal relationship deteriorates with levels of breath alcohol well within the current UK legal limit for driving. The eyes move later, and coordination reduces. These changes lead to bad performance and can be detected by an automated in-car system, which warns the driver is no longer fit to drive.