Alcohol is a neurotoxin, meaning that alcohol harms nerve cells. Chronic alcohol dependence and abuse changes brain function but the degree of change is dependent upon the duration and amount of alcohol one consumes. Alcohol is so destructive because it is a very small molecule and is able to cross the blood brain barrier and rapidly enter the brain. Because alcohol is so small, it’s size means that it can fit into many different receptors and can reach many different regions. This is why heavy alcohol dependence and consumption causes extensive brain damage.
There are 10 cells, called glia, in every nerve cell in the brain that are actively engaging in thoughts, emotions, and movements, that provide important support to nerve cells. Alcohol abuse damages both of these cell types. Losing a few critical cells due to alcohol-induced brain damage has lasting effects on decision-making, behavior and mood.