Monday 22 December, 2014

How alcohol worsens night vision among drunk drivers

Published On: Wed, Jun 18th, 2014 | Addiction | By BioNews

Know why drunk drivers see halos as they zoom past city lights, leading to traffic accidents? It’s because alcohol disturbs the tear-film that covers the surface of their eyes, leading to deterioration of vision.

Alcohol consumption markedly impairs night-vision because it increases the perception of halos (luminous circles) and other visual night-time disturbances, a new study shows.

“This is because ethanol from alcoholic drinks passes into the tear and disturbs the outermost layer of the tear-film – the lipid layer – facilitating the evaporation of the aqueous part of the tear,” said principal author of the study Jose Juan Castro from University of Granada, Spain.

In an eye with a deteriorated tear-film, the quality of the image that forms in the retina also deteriorates.

Moreover, this deterioration of vision is significantly greater in subjects with breath alcohol content in excess of 0.25mg/litre – the legal limit for driving recommended by the World Health Organisation (WHO).

To reach this conclusion, researchers evaluated retina-image quality and night-vision performance following alcohol consumption in 67 participants.

To assess visual performance in low-illumination conditions, the researchers used a visual test known as a “halometer”.

The results, published in the Journal of Ophthalmology, showed that following alcohol consumption, the perception of halos and other night-time visual disturbances increased.

Researchers also found that the optical quality of the image the eye produces deteriorated.

“Alcohol consumption and low-illumination conditions are factors present in many traffic accidents, hence people must to be made aware of the effects of alcohol consumption, especially on vision,” Castro said.

Leave a comment

XHTML: You can use these html tags: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>

More from Addiction
  • How alcohol worsens night vision among drunk drivers
  • Father’s drinking habits may alter son’s genes
  • How to keep youngsters away from hookah smoking
  • Pictorial warnings help kick the butt: WHO
  • Decoded: How do you become an alcoholic!
  • Visit us on Google+