LONDON, England (Reuters) -- Excessive drinking can damage brain cells but the brain can repair some of the harm, a team of international researchers said on Monday.
But they warned that alcoholics should get sober as quickly as possible because the longer they continue to drink heavily, the less likely their brains will be able to regenerate.
"The core message from this study is that, for alcoholics, abstinence pays off and enables the brain to regain some substance and to perform better," said Dr Andreas Bartsch, of the University of Wuerzburg, in Germany.
Slurred speech, blurred vision and an inability to walk without swaying can occur after a few drinks but chronic alcohol abuse can cause more lasting damage and poor general health.
Research in animals has shown that alcohol can disrupt the development of new brain cells in adults. Heavy drinking during pregnancy can also affect the development of the baby's brain.
Bartsch and scientists from Germany, Britain, Switzerland and Italy uncovered the brain's regenerative ability by measuring the volume, form and function of the brains of 15 alcoholic men and women before and after they stopped drinking to see how much they changed over seven weeks.
Using sophisticated scanning techniques they showed that after 38 days without a drink the brain volume of the patients increased by an average of nearly 2 percent.
"Only the one patient with the longest history of alcohol dependence had a slightly reduced brain volume," said Bartsch, whose findings are reported online by the journal Brain.
The volunteers also performed better in concentration and attention test and had higher levels of chemicals linked to brain cell function.
All of the patients had stopped drinking without medication.
"The human brain, and particularly its white matter, seems to possess genuine capabilities for re-growth," Bartsch said.