SCIENTISTS HAVE FOUND that brain functions in young men and women are changed by long-term alcohol use, but that these changes are significantly different in men and women.
This indicates not only that young people might be at increased risk of long-term harm from alcohol use, but also that the risks are probably different in men and in women, with men possibly more at risk.
A Finnish research group worked with 11 young men and 16 young women who had a heavy 10-year alcohol use, and compared them with 12 young men and 13 young women who had little or no alcohol use. All were between 23 to 28 years old at the time the measurements were taken.
The researchers examined the responses of the brain to being stimulated by magnetic pulses – known as Transcranial Magnetic Stimulation (TMS), which activates brain neurons.
Previously, the researchers had found that heavy alcohol users showed a greater electrical response in the cortex of the brain than non-alcohol users, which indicates that there had been long-term changes to how the brain responds.
This time, they found that young men and young women responded differently, with males showing a greater increase in electrical activity in the brain in response to a TMS pulse.
As one researcher, Dr Outi Kaarre of the University of Eastern Finland said:
“We found more changes in brain electrical activity in male subjects than in females, which was a surprise, as we expected it would be the other way around.
This means that male brain electrical functioning is changed more than female brains by long-term alcohol use.
The electrical impulse measurements also allowed the researchers to show that male brains have greater electrical activity associated with the GABA (gamma-amino butyric acid) neurotransmission than do female brains.
Dr Kaarre: “Generally, our work showed that alcohol causes more pronounced changes in both electrical and chemical neurotransmission in men than women.
“There are two types of GABA receptors, A and B. Long-term alcohol use affects neurotransmission through both types in males, but only one type, GABA-A, is affected in females.
We’re still trying to figure out what this means, but GABA is a pretty fundamental neurotransmitter in the inhibition of many brain and central nervous systems functions. It’s involved in many neurological systems, and is important in anxiety and depression. Generally it seems to calm down brain activity.
The study could be an important influence in how alcohol use is treated; it also shows a longterm change in brain activity despite the participants in the study not having an alcohol addiction or other disorder.
Wim van den Brink, a Professor of Psychiatry and Addiction at the Academic Medical Centre, University of Amsterdam, said these were interesting findings:
“This may mean that a different group of women is getting involved in early heavy alcohol use than used to be the case; in other words, when heavy drinking occurs more frequently and tends to become the norm, women do not need to have some aberrant personal characteristic to become an early heavy user of alcohol.
“A limitation of the study is that it says nothing about possible pre-existing neurobiological differences between the groups, an explanation for the observed differences that is equally valid”.
This work was presented today at the ECNP Congress in Paris.