Alcohol consumption during adolescence leads to serious changes in the hippocampus and may cause cognitive impairment in adulthood, reports the journal Alcoholism: Clinical & Experimental Research.
Researchers at Duke University (USA) in a study conducted in rats showed that alcohol negatively affects the developing brain of a teenager by overstimulating a process called long-term synaptic enhancement (LTP) and severely disrupting the structure of dendritic spines in nerve cells. These changes mainly occur in the hippocampus and can lead to impairment of learning and memory in adulthood.
The investigators periodically exposed the young rats to alcohol for 16 days, then allowed them to reach adulthood peacefully (without contact with alcohol), which occurred between days 24 and 29. Back then, they looked at how alcoholic drinks influenced their brain development and cognitive skills.
It turned out that the animals were hyperactivated by the LTP mechanism in the hippocampus and had thin and spindly dendritic spines in this region of the brain, the structure of which indicated immaturity.
LTP is a mechanism that allows for the enhancement of synaptic conduction and is essential for the proper functioning of learning and memory processes. LTP overactivity is related to the fact that the potential to acquire new information is exhausted too quickly and the brain simply stops learning after a while.
For an effective level of learning, the brain should maintain a balance between LTP arousal and inhibition – too much deflection in either direction causes the brain’s circuits to stop working in an optimal way, comments Scott Swartzwelder, co-author of the study.
As a result of alcohol consumption during adolescence, the way the hippocampus and other parts of the brain function and the appearance of cells change. Both LTP and dendritic spines appear to be still immature in adulthood, the researcher adds.