Published on : Jun 19, 2014
A recent research has been able to clarify the exact way how alcoholics perceive night time disturbances such as halos (luminous circles) when they drive at night. Changes in night vision performance and image quality of retina was studied in 67 participants after alcohol consumption.
The researchers used halometer to visualize the performance of eyes in dim-lit conditions, especially during night. The results suggested that the rate of perception of disturbances in night-time images and halos increase significantly after alcohol is consumed.
The reason behind this is considered to be the infusion of ethanol with the person’s tears, leading to interruption in the lipid layer of the tear film and evaporation of all the hydration in it. Thus, image quality at the retina deteriorates and perception of disturbances and halos increase.
Many earlier studies have already stressed the ill-effects of excessive alcohol consumption on body co-ordination. As alcohol has a direct impact on the brain that can impair brain functions, a series of issues such as blurred or double-vision due to weakened co-ordination of the eye muscles, delayed reaction while driving and slow response in return to oncoming headlights follow from it.
WHO recommends that alcohol contents of only 0.25mg/litre blood in humans should be considered as the maximum legal limit of alcohol content while driving as more than this reduces the quality of vision.