Drinking and the Brain: Findings that May Surprise You
A surprising connection between adolescent drinking habits and brain structure has been established by a recent study published in Experimental and Clinical Psychopharmacology. Researchers found out that drinking during adolescence is associated with larger hippocampal volumes. Interestingly, no similar relationship was found for tobacco or cannabis use. This study throws new light on how different types of substance abuse affect the developing brain in teenagers.
Effects of Teenage Substance Abuse
Substance abuse during adolescence is a major public health concern as it can have long-lasting effects on the physical and mental health of users. Adolescence is characterized by massive brain growth, making it particularly vulnerable to damage caused by drug addiction.
Adolescent substance abuse has been linked to cognitive deficits such as memory disruption and impulsivity which may persist into adulthood. Nevertheless, much of the existing neuroimaging research pertains only to heavy substance abusers, thus leaving a hole in our understanding of the less severe/recreational levels of usage effects on the brain.
Justification for Including Alcohol, Tobacco and Cannabis Abuse
This gap was addressed by this present study through examining trajectories of alcoholic drinks, tobacco and cannabis use during adolescence and gray matter volume at young adulthood. The novel approach utilized here involved concentrating not just on heavy-use vs non-use but rather looking at patterns over time which tells us about any impacts varied levels of substances exposure may have on development of the human body.
Comprised mostly of neuronal cell bodies, dendrites and unmyelinated axons, gray matter forms an important part of central nervous system which helps in processing information within brain & spinal cord hence allowing activities like muscle control, perception (sight), memory recall (intelligence) plus emotions (sentiments) amongst others like decision-making (medulla oblongata).
Description Of Method Used In The Study
As part of an investigation known as Healthy Passages Study focusing on adolescent health, the researchers selected 1,594 subjects from Birmingham in Alabama. During the first recruitment stage, they identified participants from fifth-grade classrooms and then followed them up at ages 11, 13, 16 and 19. At each of these time points, participants indicated whether they had used alcoholic drinks, tobacco or cannabis, and a subset of them (around 350) underwent Magnetic Resonance Imaging (MRI) scans around age twenty to assess brain structure.
For analysing the trajectories of substance use over time as well as estimating the initial level of use at age fourteen; the linear progression of use and acceleration/deceleration in use by latent growth curve models (LGCMs). These trajectories were then used to predict brain gray matter volume in various regions including the hippocampus, amygdala and nucleus accumbens.
Results
The researchers also learned that cortical gray matter volumes did not differ as a function of alcoholic drinks-, tobacco- or cannabis-use patterns. However, significant relationships were observed between subcortical gray matter volumes and alcoholic drinks intake patterns. Larger bilateral hippocampi were found among individuals reporting higher levels of alcoholic drinks consumption by age 14. Similarly to this finding was another one that showed positive correlation between hippocampal size and early initiation to alcoholic drinks consumption which was measured using alcohol intercept.
Neither cortices nor subcortices volumetrically differed across users using marijuana or cigarettes.
Notions to Challenge
Adolescent substance use and brain development are some of the existing notions that these findings challenge. Several studies have reported that heavy alcohol consumption is related to reduced gray matter volume in several brain regions; however, this investigation discovered that even usual, recreational drinking among adolescents correlates with larger hippocampal volumes.
The hippocampus plays a crucial role in memory formation and emotional regulation, suggesting that changes in its morphology might underlie some of the cognitive and emotional effects associated with alcoholic drinks. These results indicate that diverse patterns of alcoholic drinks use can affect brain development differently, for example early initiation is associated with higher volumes for hippocampus.
Possible Directions for Future Research
Different patterns of substance use need to be considered when examining their impacts on the developing human brain. Such relationships should be further investigated by future research given specific effects which various types of drug or alcoholic drinks consumption has. Monitoring changes occurring in the brain in relation to substance misuse through longitudinal neuroimaging studies is important as this helps understand how substance abuse occurs.
In Conclusion
According to the researchers “These results suggest that certain alcoholic drinks use trajectories (i.e., early initiation) may be the most important patterns to address through prevention and intervention programs at the population level, given their relationship with brain structure.” This study reveals new information about neural consequences of moderate adolescent drinking and can help by identifying those patterns which are more detrimental regarding prevention efforts.
Juliann B. Purcell, Nathaniel G. Harnett, Sylvie Mrug, Marc N. Elliott, Susan Tortolero Emery, Mark A. Schuster, and David C. Knight authored “Hippocampal Gray Matter Volume in Young Adulthood Varies With Adolescent Alcohol Use”.