Study drug abuse in the brain recognizable

Certain brain structures increase the risk of drug abuse

02/05/2012

Can the abuse of drugs in adolescents be recognizable in the brain? In the course of a study, adolescents were at a higher risk of experimenting with drugs or alcohol because their brain's specific properties seem to make them "more impulsive." According to this, certain brain structures are associated with an increased susceptibility to drugs. In the brain of teenagers, US scientists have been able to identify specific neural networks associated with increased drug affinity.

The international research team led by Robert Whelan and Hugh Garavan of the University of Vermont (USA) also identified a possible link between impulsive behavior and the propensity to use drugs based on the neuronal brain patterns detected. It has long been suspected that impaired impulse regulation can cause increased affinity for drugs.

Neural networks cause impulsive behavior and encourage drug use
The researchers led by Robert Whelan and Hugh Garavan investigated the brain structures of 1,896 adolescents at the age of 14 in their study. The study is part of the analysis project „Imagen“, in which European scientists collect and analyze the data of 2,000 young people from Ireland, France, England and Germany over the years. In addition to researchers from the USA, German scientists from Hamburg, Berlin, Heidelberg and Dresden were involved in the current study. The study was financially supported by the European Union. The researchers found in their research that certain neural networks can be associated with both impaired impulse regulation and a propensity for drugs. The results of their study, the researchers published in the journal „Nature Neuroscience“. Whelan and colleagues used functional magnetic resonance imaging (fMRI) to record 14-year-olds' brains during a series of experiments to determine the brain structures of adolescents. As part of the experiments, for example, the teenagers should hold down a button for a certain period of time or stop the press of a button at the last minute before the time runs out. Here the adolescents with impaired impulse regulation are more likely to have difficulties than the adolescents with good impulse control.

Impaired pulse regulation causes increased susceptibility to drugs
In the study, the researchers also interviewed the adolescents on their previous drug experience and also considered genetic factors. They found that adolescents with impulsive behavior or impaired impulse regulation tended to be more likely to use drugs, tobacco, and alcohol than others. For the affected adolescents, the researchers were able to detect a subfunction of a fMRI „certain orbitofrontal cortical network“ determine. This reduced activity in the neuronal network of the orbitofrontal cortex makes adolescents more impulsive as well as more adventurous in alcohol, cigarettes and illicit drugs, write Whelan and colleagues. Current study results also help to clarify the chicken-or-egg question as to whether or not certain brain patterns were present prior to drug use, reports the University of Vermont.

Link between ADHD and increased affinity for drugs?
The link between impaired impulse control and drug affinity has been demonstrated in numerous studies. In particular, the link between attention-deficit / hyperactivity disorder (ADHD) and drug-susceptibility was at the center of public interest, according to researchers from the University of Vermont. Because both ADHD and early drug use have been associated with poor impulse control. However, the scientists around Robert Whelan and Hugh Garavan could prove in the context of their study that „These seemingly same problems are regulated by different networks in the brain“, reports the University of Vermont. This reinforces the idea that the risk of ADHD does not necessarily entail an increased risk of drug use.

Recognize the risk of drug use based on neural networks?
Overall, the researchers made a significant contribution to the understanding of impulse regulation in the brain and its associated susceptibility to drugs. The current findings may also help in the early determination of the susceptibility of adolescents to drugs, the researchers hope. The essential message was however, „that impulsivity breaks down and spreads to different brain regions“ can be broken down, taking „the functioning of one region is related to ADHD symptoms, while the function of other regions is related to drug use“, explained Hugh Garavan. (Fp)