As a recovered(ing) alcoholic, I want to say that when I got sober, I
studied alcoholism for quite some time.  (Know your enemy, as it were)  The
gist of the studies seemed to indicate that every time an individual drank
to intoxication, brain cells were destroyed.  With chronic alcoholism, this
problem was not only exacerbated, but obvious in the mental condition of
the drinker.  From my own personal experience, I will say that it took me
almost 3 years of complete sobriety to reach the point where I felt my mind
had recovered.  Some of the symptoms were memory lapses (which, admittedly,
could have been caused by any number of things, but under the
circumstances, the most obvious cause was the alcoholism), inability to
concentrate (ditto), and depression, as well as irrational reactions.
These symptoms gradually subsided over this period of time.  Although it is
my understanding that brain cells do not regenerate in the same way that
other tissue cells do, there are enough "spare" cells in the brain to take
over many of the functions of damaged or killed cells over a period of time
(witness stroke victims who learn to walk and talk again).  The only
difference between medicinal ether and beverage alcohol is one molecule of
water.

Liz