Brain Scan Test May Predict Teens Who Will Abuse Drugs
According to a new study, brain scans may help to predict whether teenagers will be likely to abuse drugs.
Researchers say that teens who the most prone to drug abuse are often impulsive and smart, but not terribly engaged. These traits may serve as a warning, but not all adolescents who have these characteristics become drug abusers.
The study was developed through a collaboration between Stanford and Hamburg-Eppendorf in Germany. With help from the Stanford Neurosciences Institute’s NeuroChoice program, researchers began examining data from tests taken by 144 European teenagers. These teens scored high on what’s known as “novelty-seeking” behavior.
Novelty seeking can be good or bad – it can result in innovation and new experiences, but it can also cause people to become reckless and make rash and unhealthy decisions.
This group of adolescents exhibited traits that may reflect a heightened risk for alcohol or drug abuse. Indeed, young people who score high on tests regarding novelty-seeking are more likely to abuse substances.
Researchers wanted to know, however, if was there a better, more precise test that could reveal which teens who exhibited novelty-seeking behavior were more prone to substance use.
The Brain Scan
Thus, they turned to a brain scanning test known as the Monetary Inventive Delay Task (MID). One of the researchers had developed the test earlier in his career, and used it as means to target a brain region associated with reward processing, such as money or drug highs.
During the test, people lie in an MRI brain scanner and play a video game for points that they can ultimately convert to money.
At the beginning of each round, the player receives a hint about how many points he or she could potentially win during that round.
At this point, players begin to foresee future rewards, and consequently, most people’s brain reward centers are activated.
But among teens who use drugs, the brain responds differently – and in a way that is a bit baffling. You see, compared to the adult brain, children’s brains, generally speaking, exhibit less response during reward anticipation.
But this effect is even more marked when those children use drugs.
This finding reveals one of two facts: one, the drugs are suppressing brain activity, or two, the suppression of brain activity contributes to the young person’s propensity to use drugs.
If it is the latter, then the brain scan test may predict drug use in the future.
But most researchers were not certain, however, because brain activity in clean/sober teenagers had not been measured or compared to eventual drug abuse – except by one researcher in Germany.
This researcher had amassed data on about 1,000 14-year-olds using the MID task. Also, each was followed up two years later and asked if they’d become drug abusers, such as using a substance daily or hard drugs such as heroin.
Novelty-Seeking Behaviors and Brain Scan Results
Then, researchers focused on the 144 teens who had not development drug problems by age fourteen, and yet had scored in the top 25% on the novelty-seeking test. Upon analysis, researchers discovered that they could accurately predict if the teens would eventually abuse drugs around 2/3 of the time.
While not 100% perfect, this revealed a significant improvement over behavioral and personality trait measurements, which were correct a little more than half of the time – just a tad bit better than mere chance alone.
According to the researchers, this study needs to be replicated, and more follow-ups conducted on the teenagers in the sample.
However, this finding is a step in the right direction, and one day physicians may be able to use such tests on individual patients to intervene and prevent drug abuse before it begins.
Other Risk Factors
The assumption behind the brain scan is that certain inherent neurological characteristics contribute to a person’s propensity for substance abuse or addiction. However, there are other risk factors, as well that are social or environmental in nature. They may include:
- A lack of parental supervision, child abuse or maltreatment, as well as childhood trauma and stress.
- Neighborhood poverty and violence.
- Poor academic performance due to struggles with school structure or content, especially when adolescents are confronted with peer pressure.
- Parents who abuse drugs and alcohol themselves or who suffer from mental illness.
- The availability of drugs in the immediate environment, including norms and laws that favor substance abuse.
The more risk factors that are present, whether biological or social/environmental, the greater the cumulative risk of a teenager engaging in the harmful use of substances.
~ G. Nathalee Serrels, M.A., Psychology
Blunted ventral striatal responses to anticipated rewards foreshadow problematic drug use in novelty-seeking adolescents. Nature Communications 8, Article number: 14140 (2017) doi:10.1038/ncomms14140.