Children who start drinking alcohol before the age of 15 may already exhibit distinctive patterns in their brain organization years earlier, according to a study published in Translational Psychiatry. The findings suggest that specific brain network characteristics may serve as early markers of vulnerability to alcohol use in adolescents.
Starting alcohol use at a young age has long been associated with an increased risk of later alcohol problems, mental health problems, and other negative outcomes. Scientists have previously identified differences in brain structure in adolescents who consume alcohol, but most studies have focused on specific brain regions. More and more researchers are viewing the brain as an interconnected network, raising questions about whether the organization of the brain as a whole can reveal risks that cannot be uncovered in individual regions.
The researchers wanted to see if brain differences existed before alcohol consumption began. Identifying such differences could help explain why some young people are more likely to start drinking alcohol earlier than others.
The team, led by Holly Byrne from the Matilda Center for Mental Health and Drug Use Research at the University of Sydney, analyzed data from the Adolescent Brain Cognitive Development (ABCD) study. The researchers examined MRI scans collected when participants were between 9 and 10 years old, and then compared those who had consumed all alcoholic beverages before the age of 15 with those who had not. The primary analysis used a matched group of 160 early initiators and 160 noninitiators.
The study found little evidence that prospective drinkers differ from other drinkers in specific areas of the brain. The researchers found that a number of statistical tests performed could not reliably distinguish individual brain regions between children who started drinking later in life and those who did not.
However, when the research team examined the brain as a network, a different picture emerged. Children who started drinking alcohol later showed lower network segregation. This means that groups of adjacent brain regions appeared to be less specialized. It has also been shown that the network is highly integrated and efficient, indicating strong but atypical communication across distant regions of the brain.
“The pattern of lower segregation and higher integration is consistent with a neuroanatomical profile suggesting disrupted or atypical cortical maturation,” Byrne et al. noted.
They also found that future drinkers reported higher levels of sensation seeking, a personality trait associated with risk-taking behavior. The groups were otherwise similar on psychological, behavioral, and cognitive measures.
Dr. Byrne’s team concluded, “These findings suggest that the network topology of cortical thickness at ages 9 to 10 years may serve as a neuroanatomical risk marker for alcoholism in early adolescence.”
The researchers caution that the study has some limitations. The number of youth who started drinking early was relatively small, which may have reduced the stability of some of the findings. Additionally, demographic matching cannot fully account for cultural, social, and environmental influences that can shape both brain development and alcohol use.
The study, “Characteristics of brain networks before early adolescent alcohol onset,” was authored by Holly Byrne, Ryan Visontay, Erin K. Devine, Natasha E. Wade, Joanna Jacobus, Lindsay M. Scuglia, and Lexine Muton.
