What is it that makes members of the opposite sex more attractive to people under the influence of alcohol? Is it just impaired judgement? A team of researchers led by Cho Hyun-gug, a professor of visual optics at Kyungwoon University, say the reason is that alcohol consumption decreases vision and makes faces appear less clear.
Cho's team asked 10 adults with an average age of 22.4 years and with healthy vision to consume one bottle of soju (360 ml) in 30 minutes. The soju had an alcohol content of 19.7 percent.
One hour after drinking, the blood-alcohol level was at its highest at 0.32 percent and the participants' vision had fallen 0.32 diopters from when they were sober. Three hours later, their blood-alcohol level was 0.17 percent and their vision down 0.27 diopters. Participants' vision was slightly more distorted when they were under the influence of alcohol.
A decrease of one notch on a vision test chart signifies a vision decline of 0.15 diopters. Park Sung-bae, an optometrist at Bundang Cha General Hospital, said, "A 0.3 diopter decline means a person with 1.0 vision is now at the 0.8 level. This increases distortion, so the facial features of the opposite sex appear less clear and may look more attractive."
The findings were published in the Journal of the Korean Ophthalmic Optics Society.