(RxWiki News) Researchers have found that drug-abusers have trouble identifying negative emotions in the facial expressions of others.
For this study, scientists at the University of Granada set out to examine the relationship between drug abuse and recognition of basic emotions, including happiness, surprise, wrath, fear, sadness, and disgust. In order to analyze this relationship, they conducted neuropsychological evaluations on 123 polysubstance abusers (those who abuse multiple drugs) who consumed drugs such as cocaine, marijuana, heroin, alcohol, MDMA, and methamphetamine. In order to create a control group, the scientists conducted the same evaluation on 67 individuals who did not use any drugs.
María José Fernández Serrano, of the Department of Personality and Psychological Treatment and Evaluation at the University of Granada, and colleagues found that 70 percent of drug-abusers had some form of neuropsychological deterioration. More specifically, the study revealed major deterioration in the working memory, fluency, flexibility, planning, and multitasking.
The study's results also show that drug-abusers had difficulties recognizing negative emotions (wrath, disgust, fear, and sadness) in the facial expressions of others. Those who regularly abused alcohol, cannabis, and cocaine were more likely to adversely affect their fluency and decision-making skills. The abuse of cocaine and cannabis was damaging to memory and reasoning.
Many of these findings do not come as a surprise. However, using the aggregate information from this study, researchers and policymakers can develop effective rehab programs that take into account the varying neuropsychological profiles among drug-abusers.
According to the 2009 National Survey on Drug Use and Health, nearly nine percent of Americans 12 years of age and older said they used an illicit drug within one month before the survey. That's nearly 22 million people. The most commonly used illicit drug was marijuana, with about three-quarters of drug users reporting marijuana use.
The University of Granada findings appear in articles published in four different journals: Neuroscience and Biobehavioral Reviews, Journal of Psychopharmacology, Drug and Alcohol Dependence, and the European Journal of Pharmacology.