Korsakoff’s syndrome, which is also known as amnesic-confabulatory syndrome or Korsakoff’s psychosis, is caused by a deficiency of thiamine or vitamin B1 in the brain. The disorder is named after the Russian neuropsychiatrist, Sergei Korsakoff, who discovered and popularized the theory.
How does Korsakoff’s syndrome manifest itself?
There are six major symptoms of Korsakoff's syndrome:
- Anterograde Amnesia - a loss of memory of what happens after the injury that caused the amnesia.
- Retrograde Amnesia - where events prior to the injury-causing one are forgotten. To a large degree, anterograde amnesia remains a mysterious ailment because the precise mechanism of storing memories is not yet well-understood, although scientists know which regions of the brain are involved.
- Apathy- individuals don’t have interest in things for very long and seem indifferent to change.
- Little content is offered in conversations and a lack of insight.
- Confabulation – are memories that are invented to fill in gaps of memories. These gaps are usually associated with blackouts.
Other signs that are associated with Korsakoff’s include:
- Paralysis of eye muscles
- Lack of insight into the severity of the condition
How does this occur?
There are several conditions or behaviors that can lead to Korsakoff’s including:
Chronic alcoholism which is automatically correlated with vitamin deficiency and malnutrition is a precursor to Korsakoff’s. As alcohol can irritate and inflame the stomach lining, thiamine deficiency can occur.
Other dietary deficiencies causing Korsakoff’s include prolonged vomiting, eating disorders, or from the effects of chemotherapy. This can also occur in pregnant women due to a condition known as Hyperemesis Gravidarum, which is extreme morning sickness. Mercury poisoning has also been known to cause the disorder.
What is the mechanism in the brain that causes Korsakoff’s?
The symptoms mentioned above are caused by a deficiency of vitamin B1 or thiamine. This is thought to cause damage to the medial thalamus of the brain as well as damaging parts of the hypothalamus. In addition, thiamine deficiency can lead to an overall cerebral atrophy. This disorder involves neuronal loss, or damage to the neurons. In addition, gliosis can occur which is damage to the cells which support the central nervous system. The lack of thiamine and malnutrition can lead to the hippocampus decaying; leaving holes that cause ones short term memory to transfer into long term memory (see anterograde amnesia).
How Korsakoff’s is treated?
As the individual is lacking thiamine, treatment takes place by replacing the missing vitamin. Thiamine is replaced by intramuscular or intravenous injection. In addition, the proper nutrition or hydration is required. Regardless of how much of the thiamine is replaced, the amnesia and brain damage that are caused by the disease do not respond to thiamine replacement. Even if treatment is successful, it often takes two years for some sign of recovery. In cases where recovery is achieved, it is slow and may not be complete.
Prevention of Korsakoff’s
The best way to avoid this syndrome is by making sure that a thiamine deficiency does not result. As the most common cause of thiamine deficiency in the Western world is alcoholism it should be quite clear that alcohol in excess should be avoided. It should be made clear that this deficiency does not result in an absence of thiamine in the diet, but rather a resistance on part of the body to properly absorb the nutrients. Alcohol can cause inflammation of the stomach and the intestines which is where nutrients are soaked in. At one point in time, thiamine was added to alcoholic beverages; however, it did not assist alcoholics. The addition of alcohol has been blocked by the U.S. governments as some political groups attest that adding thiamine to alcohol would further encourage excess drinking.
In addition to the effects of thiamine deficiency, alcohol is neurotoxic which means with time, the neurons (part of the brains framework and ‘communication’ system) can become damaged; specifically focusing on the hippocampus. This is the area responsible for short term memory and spatial thinking. When one consumes alcohol, the body releases cortisol, a stress hormone. In excess, it has been found that cortisol cause further damages to the hippocampus which may be irreversible if present for a long period of time. Using alcohol in moderation will not cause Korskoff, however, continued use can cause all of the effects mentioned above including dementias. This may give one something to think about before picking up that first or second glass of wine, or bottle of beer.
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Kessels RP, Kortrijk HE, Wester AJ, Nys GM. (2008). Confabulation behavior and false memories in Korsakoff's syndrome: role of source memory and executive functioning.
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