Researchers at the University of Pittsburgh School of Medicine used brain scans to look at the links between genetics, brain structure, alcohol problems and impulsivity. They gave brain scans to 107 teenagers and young adults. 63 of them were in a high-risk group with several relatives with alcohol problems while the remainder had no close relatives with alcohol or drug problems. Those youngsters in the high-risk group were more likely to have variations in the genes 5-HTT and BDNF that in turn led to a reduction in the size of an area of the brain called the right orbito-frontal cortex - which is involved in regulating emotional processing and impulsive behaviour -leading them to become more impulsive. These differences were observed even if the youngsters in the high-risk group were not drinking excessively suggesting that they were risk factors for alcohol problems, not the consequences of them.
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