The next time you have an alcohol binge and think you can easily drive home, remember that this may not be the case. For, new research suggests that your reasoning and problem-solving abilities remained impaired for longer durations by alcohol than you actually believe them to be.

The study, published in the latest issue of the medical journal Experimental and Clinical Psychopharmacology, reviews on the age old problem of how a person's cognitive abilities are affected when blood alcohol concentration (BAC) rises and falls.

The BAC, which is a measure used to determine the levels of intoxication, was measured in a group of volunteers who consumed liquor within a laboratory during an eight-hour period. During this period, their BAC rose to 0.10 percent before they were asked to wait and bring them down to normalcy.

The team of observers sat alongside the volunteers and as their BAC levels rose and then fell, asked them to describe their feelings of drunkenness. Experiments included testing their ability to navigate a hidden maze on a computer.

While the sober adults made very few mistakes during the test, the errors grew dramatically as the experiment progressed and the BAC levels began rising. What was intersting was that the errors did not decline dramatically when the participants felt less drunk.

The researchers used various types of cognitive functioning as part of the computer test. Many of these functions are critical for driving and making judgments in terms of crossing intersections, changing lanes or parking a vehicle.

It was observed that executive functions do not recover as quickly after drinking as basic functions like motor speed and information processing speed. Lead author Peter J. Snyder, vice president of research for Lifespan, a not-for-profit healthcare system based in Providence, Rhode Island, noted that the subjective feeling that a person is drunk recovers faster.

"This explains why so many individuals feel subjectively that they are able to get into a car and be able to drive and feel safe. But that subjective impression does not mesh with the actual recovery in terms of higher order executive functions," says Snyder in a press statement issued by Lifespan.