According to a recent study from Kuopio University Hospital and the University of Eastern Finland, heavy alcohol use during adolescence alters the development of the brain. Young people who had been heavy drinkers throughout their adolescence developed cortical thinning.
Magnetic resonance imaging of the brain structure was used in the study. The participants were young and healthy adults who had been heavy drinkers throughout their adolescence, while the control group consisted of age-matched light-drinking participants. Three cross-sectional studies were conducted over the course of ten years – in 2005, 2010 and 2015. At the start of the study, the participants were between 13 and 18 years old.
The prevalence of mental health problems did not differ between the two groups and all participants were academically successful. None of the heavy drinking participants had been diagnosed with alcohol use disorder, although they had used approximately 6-9 units of alcohol roughly once a week regularly for ten years.
Statistically significant differences between the groups was revealed by magnetic resonance imaging of the brain. Grey matter volume was decreased in the right insula as well as in the anterior cingulate cortex bilaterally among the heavy drinking participants
PhD Student Noora Heikkinen, the first author of the study noted that the brain still matures during adolescence, with the frontal areas and the cingulate cortex still developing until the twenties. He added that the findings indicate a strong probability that heavy alcohol use may disrupt this maturation process.
The cingulate cortex plays an important role in impulse control. Volumetric changes in this area may contribute to the development of a substance use disorder later in life. On the other hand, structural changes in the insula may reflect a reduced sensitivity to alcohol’s negative subjective effects and contribute to the development of a substance use disorder in this way.
Heikkinen notes that although the exact mechanism behind these structural changes is not known, it has been suggested that if alcohol consumption were to be reduced significantly, some of the volumetric changes may be reversible.