Studies suggest that recreational use of cocaine is associated with significant impairments in the same cognitive control functions affected by chronic use. Are up to 4 grams monthly enough to damage the ability of suppressing irrelevant information?
Second preferred recreational drug
Over the last 10 years, taking cocaine by snorting route has become the most common recreational drug habit in Europe after smoking cannabis. The increasing use of cocaine has become a serious public health issue both in Europe and in the USA, especially because of the well-known addictive properties of this psychostimulant drug and its detrimental effects on cognitive functioning (European Monitoring Center for Drugs and Drug Addiction 2012).
Recreational use as dangerous as chronic use
Recent studies from our lab have shown that even recreational cocaine users, who do not meet criteria for abuse or dependence but take cocaine (preferably by snorting route) on a monthly frequency (1 to 4 g monthly), show similar cognitive impairments as chronic users consuming cocaine on a much more regular basis (often 1g daily, but at least 3g weekly).
Cocaine use enhances distraction
For the first time, in our new study published in Experimental Brain Research we compared recreational cocaine polydrug users and cocaine free-controls on the Simon task—in which participants have to ignore irrelevant information on a computer screen. We found that users were more distracted from the irrelevant information than nonusers. This means that up to four grams of cocaine monthly, for at least 2 years, seems to be enough to damage interference control, the ability of suppressing irrelevant information.
Even though the task we used to diagnose interference control in recreational users is rather artificial, the deficit itself is likely to affect everyday behavior. Many real-life situations require the ability of suppressing distraction. This is particular obvious for examples like traffic behavior, where stopping to walk or to drive is necessary when the traffic light turns from green to red, or when passengers, animals, or vehicles are suddenly crossing the street.