"We made a special effort in this study to include only people who did not have any of the things that other scientists think might make the hippocampus smaller, such as post-traumatic stress disorder," said Beresford. "By excluding these people, we could focus only on the effects of chronic, heavy drinking."
Study results indicate a reduction in total hippocampus volume among the alcoholics.
"When we took a picture of the alcoholic brains using MRI, and measured the hippocampus," said Beresford, "it was much smaller than the hippocampus in the group of people who did not drink alcohol heavily. This means that alcohol appears to injure the hippocampus by itself. That is, it may harm the hippocampus in a way that other things do not."
"These findings may explain some of the memory impairment and cognitive deficits described in chronic alcoholics," added Wand. "It is unclear if the effect is reversible. It has been shown that stress-induced effects on hippocampal volume are reversible." Wand suggested future studies use a larger sample of subjects, and also noted given that alcoholism is partially an inherited disorder that persons predisposed toward alcoholism might already have a smaller hippocampus prior to the onset of heavy drinking compared to persons not predisposed.
Beresford agreed. "This study is only a first step," he said. "We are now studying what happens to the hippocampus in heavy drinkers when they stop drinking, whether the hippocampus heals itself or not, and what we might do to help healing along. Since the hippocampus is connected to many other parts of the brain, it is difficult to know all of the things that it