I am only addressing the extreme end of the spectrum of chronic alcohol abuse:
One syndrome that is known to develop from chronic alcohol abuse id Korsakoff's syndrome or Wernicke-Korsakoff syndrome.
It causes memory loss and a form of dementia. An irreversible brain damage that permanently disables the individual. The individual is unable to function within society and carry out the daily tasks necessary for functional living. It can also include psychosis.
Korsakoff syndrome is most commonly caused by alcohol misuse,...//...
Korsakoff syndrome causes problems learning new information, inability
to remember recent events and long-term memory gaps. Memory problems
may be strikingly severe while other thinking and social skills are
relatively unaffected. For example, individuals may seem able to carry
on a coherent conversation, but moments later be unable to recall that
the conversation took place or to whom they spoke.
Those with Korsakoff syndrome may "confabulate," or make up,
information they can't remember. They are not "lying" but may actually
believe their invented explanations. Scientists don't yet understand
why Korsakoff syndrome may cause confabulation. (1)
Scientists don't yet know exactly how Korsakoff syndrome damages the
brain. Research has shown that severe thiamine deficiency disrupts
several biochemicals that play key roles in carrying signals among
brain cells and in storing and retrieving memories. These disruptions
destroy brain cells and cause widespread microscopic bleeding and scar
Lack of vitamin B1 is common in people with alcoholism....//..
Korsakoff syndrome, or Korsakoff psychosis, tends to develop as
Wernicke symptoms go away. Wernicke encephalopathy causes brain damage
in lower parts of the brain called the thalamus and hypothalamus.
Korsakoff psychosis results from permanent damage to areas of the
brain involved with memory. (2)
Symptoms of Wernicke encephalopathy include:
- Confusion and loss of mental activity that can progress to coma and
- Loss of muscle coordination (ataxia) that can cause leg tremor
- Vision changes such as abnormal eye movements (back and forth
movements called nystagmus), double vision, eyelid drooping
Alcohol withdrawal Symptoms of Korsakoff syndrome:
- Inability to form new memories
- Loss of memory, can be severe
- Making up
- Seeing or hearing things that are not really there (hallucinations) (2)
(1) Korsakoff Syndrome
(2) A.D.A.M. Medical Encyclopedia.
Korsakoff psychosis; Alcoholic encephalopathy; Encephalopathy - alcoholic; Wernicke's disease
Last reviewed: February 27, 2013.