April 2014 Almost one-third (32 percent) of the roughly 42,000 Monitoring the Future survey respondents reported having used marijuana during their lifetime. However, abuse of many other drugs—methamphetamine, heroin, cocaine, and some prescription medications—declined.
Methamphetamine alters brain structures involved in decision-making and impairs the ability to suppress habitual behaviors that have become useless or counterproductive. The two effects were correlated, indicating that the structural change underlies the decline in mental flexibility.
January 2014 Researchers have shut down laboratory rats’ compulsive cocaine seeking by stimulating an area of the animals’ prefrontal cortex. The finding raises the possibility that stimulating neurons in this brain area may weaken or break cocaine’s grip on the behavior of people who are addicted to the drug.