You don't have to be blitzed to be blind drunk, a new study shows.
One stiff drink is all it takes to cause "inattentional blindness," a condition where people fail to detect unexpected objects in their field of vision while focusing on another task.
The study reveals that people who are at half the legal intoxication limit in the United States—which is set at .08 blood alcohol concentration—were heavily compromised in their ability to notice an unexpected visual object while focusing on another simple task.
Hey, was that a gorilla?
The researchers served the participants drinks, which unbeknownst to the subjects either contained alcohol or did not.
After downing their drinks, the participants watched a 25-second video clip of six people playing with a ball. They were instructed to count the number of passes.
Halfway through the video, a person dressed in a gorilla suit ran through the game beating its chest.
Subjects who had consumed the alcoholic beverage were twice as likely to miss seeing the gorilla, even though it was onscreen for nearly a third of the test.
Driving home the message
While the researchers didn't directly test driving aptitude, study leader Seema Clifasefi of the University of Washington believes the implications could be serious.
Drivers rely on their ability to perceive information from several visual sources as they head down the road. If even a mild amount of alcohol disrupts this ability in the lab, it might do the same behind the wheel.
In a separate study released earlier today, researchers said the same inattentiveness affects people who drive while talking on cell phones.
"If you've had one drink, you may be so focused on paying attention to your speed so as not to get pulled over, that you completely miss seeing the pedestrian that walks directly in front of your car," Clifasefi said.
The study is detailed in the July issue of the Journal of Applied Cognitive Psychology.