The University of Maryland Medical Center explains that 18 million Americans abuse alcohol. When a person is an alcoholic, she has a physical dependency on alcohol. If an alcoholic stops using alcohol, she has withdrawal symptoms along with cravings. Examples of withdrawal symptoms include tremors, irritability and sweating. The alcoholism can become progressively worse, leading to serious problems, such as amnesia or memory loss.
Types of Amnesia
The MayoClinic.com defines two types of amnesia: retrograde amnesia and anterograde amnesia. With retrograde amnesia, patients have problems recalling stored memories, or information that they have already learned. Anterograde amnesia affects patients' ability to create new memories. Alcoholics can have one or both types of amnesia, depending on the extent of the alcohol's damage on the brain.
Blackouts
Even if a person has only a few drinks, the alcohol can affect memory. Termed a blackout, this type of memory loss spans a period of time when the person is intoxicated. That person cannot remember what happened during the blackout. For example, if a person had intercourse during a blackout, he would not remember it occurred when he became sober. Blackouts occur when people drink large amounts of alcohol quickly on an empty stomach. The National Institute of Alcohol Abuse and Alcoholism points out that women may be more susceptible to blackouts, even when they consume the same amount of alcohol as men.
Damage to the Hippocampus
When people drink heavily, the alcohol can damage the hippocampus, an internal brain structure involved in memory. The hippocampus' role in memory is consolidation, which is the process that converts short-term memories--temporary memories--to long-term memories--permanent memories. The National Institute of Alcohol Abuse and Alcoholism explains that alcohol damage to the CA1 region of the hippocampus, a part of the hippocampus, affects the formation of new explicit memories. With explicit memories, like a fact, a person has to recall it consciously. In comparison, implicit memories, such as riding a bike, are not consciously recalled. Alcohol can also damage the frontal lobes, which can affect both short-term and long-term memories.
Thiamine Deficiency
The amount of alcohol that an alcoholic consumes affects his absorption of thiamine, also called vitamin B1. The National Institute of Alcohol Abuse and Alcoholism notes that up to 80 percent of alcoholics have a thiamine deficiency. A deficiency of thiamine can lead to Wernicke-Korsakoff syndrome, a serious neurological disorder that can result in permanent amnesia.
Wernicke-Korsakoff Syndrome Symptoms
Wernicke-Korsakoff syndrome is a two-part syndrome. After patients have Wernicke's encephalopathy, it progresses to Korsakoff syndrome, the part of the disorder that causes amnesia. Patients with Korsakoff syndrome cannot form new memories and also have severe memory loss. MedlinePlus explains that to make up for the gaps in memory, patients confabulate, in which they make-up stories. Korsakoff syndrome patients who confabulate do not realize that their stories are false.
References
- University of Maryland Medical Center: Alcoholism
- MedlinePlus Medical Encyclopedia: Wernicke-Korsakoff Syndrome
- National Institute of Alcohol Abuse and Alcoholism: What Happened? Alcohol, Memory Blackouts, and the Brain
- National Institute of Alcohol Abuse and Alcoholism: Alcohol's Damaging Effects on the Brain
- MayoClinic.com: Amnesia Symptoms
