The highly addictive drug methamphetamine (“meth”) causes dramatically more damage to the brains of adolescents…
Meth Damages Brains of Teens Far More Than Adults
Chronic teenage consumers of methamphetamine experience substantially more damage to their higher-level mental functions than their adult counterparts, according to new findings from a team of American and South Korean researchers.
Methamphetamine is known for its ability to produce a relatively rapid and severe form of substance addiction. Among the drug’s many harmful effects is damage to the brain areas responsible for carrying out a group of higher-level mental skills known collectively as executive function. In a study published in February 2015 in the journal Molecular Psychiatry, researchers from three South Korean universities and one American university used brain scans to compare the executive function-related brain changes found in teenagers who regularly consume methamphetamine to the changes found in adults who regularly consume the drug.
Methamphetamine’s Brain Impact
All mind-altering stimulant drugs (including cocaine and amphetamine) are capable of triggering physical dependence and addiction by upsetting the chemical balance in a part of the brain called the pleasure center. Methamphetamine, a close relative of amphetamine, produces unusually profound changes in the pleasure center’s chemical environment and therefore has the potential to set the stage for dependence and addiction more rapidly than other stimulants. In addition, the severity of addiction symptoms in a chronic meth user may in some cases be substantially worse than the severity of the symptoms found in chronic users of other stimulant drugs.
Unfortunately, the negative brain impact of chronic methamphetamine consumption goes far beyond the onset of dependence and addiction. Specific additional problems associated with repeated, long-term use of the drug include significant structural alteration of the grey matter and white matter found in several brain areas and significant alteration of the brain’s baseline ability to function. In addition to disruption of executive function, known consequences of these brain changes include mood swings, episodes of uncharacteristically violent behavior, sleeplessness, bouts of anxiety and symptoms of psychosis that may include such things as a paranoid mental state, hallucinations and delusional thoughts and beliefs. Some of the brain damage caused by chronic meth use may heal after the establishment of a sustained pattern of abstinence. However, some degree of residual damage commonly remains in the brains of recovered users of the drug.
Teens and Meth Consumption
Findings from an annual, federally sponsored survey project called Monitoring the Future indicate that about 1 percent of American teenagers enrolled in the 12th grade used methamphetamine at least once in 2014. Roughly half this percentage of 12th graders used the drug at least once a month. Among 10th graders, the yearly rate of meth use was 0.8 percent; 0.3 percent of teens in this grade used the drug in any given month. Among eighth graders, the yearly rate of methamphetamine intake was 0.6 percent; 0.2 percent of eighth graders used the drug on a monthly basis. Meth use among all U.S. teenagers has fallen substantially since the beginning of the 21st century.
Impact on Teenagers’ Brains
In the study published in Molecular Psychiatry, researchers from the University of Utah and South Korea’s Ewha Womans University, Catholic University of Korea and Soonchunhyang University used MRI brain scans of 111 South Korean teenagers and 114 South Korean adults to compare the brain damage caused by chronic methamphetamine use in each of these age groups. Each group of study participants was roughly divided between meth consumers and non-consumers. The researchers looked for changes in gray matter (the nerve cells that form the brain’s active communication networks) and white matter (the nerve cells that provide support for gray matter) in all of the participants.
After reviewing the results of the scans, the researchers concluded that the damage found in the brains of teenage chronic meth consumers is significantly worse than the damage found in the brains of adult chronic consumers of the drug. Crucially, this finding applies to the brain areas responsible for executive function, a suite of mental skills that includes the ability to think logically, the ability to control impulsive behavior, the ability to make situation-appropriate judgments and the ability to make achievable plans for the future.
The study’s authors note that teenagers have not yet completed the stage of brain development that finalizes their ability to use executive function. This means that, effectively, chronic methamphetamine use or meth addiction may permanently disrupt an adolescent’s higher-level mental functions. The authors also note that teens typically consume methamphetamine in smaller amounts than their adult counterparts. This essentially means that adolescents experience severely negative outcomes at a much lower rate of meth intake than adults.