Brain imaging of neuromelanin may be key to understanding extensive substance use

A study using a specialized type of magnetic resonance imaging (MRI) – neuromelanin-sensitive MRI – showed that this type of MRI signal was increased in areas of the midbrain in young adults aged 20 to 24 who had consumed a lot of alcohol and history of drug use.

The study was conducted by a team of researchers from the Department of Psychiatry and Behavioral Health at the Renaissance School of Medicine at Stony Brook University. The findings are published in the American Journal of Psychiatry.

The study involved 135 people, 105 women and 30 men. Neuromelanin naturally accumulates in areas of the midbrain where the neurotransmitter dopamine is produced. Dopamine plays an important role in many cognitive and physical functions and plays a central role in the reward/motivation system in the brain. Dopamine can be difficult to study in young people. This has hindered researchers’ understanding of the early stages of certain neurological diseases and mental health conditions, such as addictive behavior in adolescents. However, neuromelanin accumulation in young people can be safely and easily examined using neuromelanin-sensitive MRI.

“Young adults who use regular substances appear to show greater than normal accumulation of neuromelanin on this type of MRI scan, especially young women,” said Greg Perlman, Ph.D., assistant professor of Psychiatry and Behavioral Health and lead author.

“This is important because much of the biomedical research on the effects of drug and alcohol use on the dopamine system has examined older adults after years or decades of chronic substance use. In contrast, there is very little information about the dopamine system in adolescents or adults. young adult populations after just a few years of habitual alcohol and drug use. The potential of neuromelanin-sensitive MRI to provide new insights into the health of the dopamine system in youth was an important motivation for our study.

Perlman indicated that the association between substance use and MRI signals of neuromelanin was especially strong in certain midbrain regions of young women, such as the ventral tegmental area. Furthermore, increased neuromelanin was associated with substance use in general, but not with the use of any one type of drug.

The research team is currently conducting a new study using neuromelanin-sensitive MRI in teens aged 14 to 17 to better understand neuromelanin accumulation over those three years of life. The study will use annual MRI scans to evaluate the effect of life experiences reported by teens, such as alcohol consumption, social media use and stressful events, on neuromelanin accumulation measured by neuromelanin-sensitive MRI.