Multiple Personality May Hide Behind Alcohol Abuse

Let’s say that someone has reported episodes of out-of-character behavior; for example, the person has acted violent or promiscuous or spendthrift or suicidal or crazy. Furthermore, these episodes have occurred only when the person was drinking, and there was amnesia for the episodes afterwards. (They know about the incidents from partial memory, circumstantial evidence, or witnesses.)

What happened? Uninhibited behavior during alcoholic blackouts? Is alcohol abuse the person’s only problem?

They might have two problems, alcohol abuse and multiple personality, if the latter includes an alternate personality who drinks.

If the problem is only alcohol abuse, then the person really doesn’t have any memory of the episodes, since the toxic effect of alcohol on the brain prevented any memories from being formed in the first place. [added July 11, 2014: Some books do say that memories of true alcohol blackouts, by definition, are not recoverable. But it may not be true. And if it is really not that uncommon for blackout memories to be recoverable—such as during the next time the person drinks, or just spontaneously after a period of time—then either "state-dependent memory" can easily happen apart from multiple personality or multiple personality hides behind alcohol abuse more often than I thought. So I will come back to this issue after reading more about alcoholic blackouts.]

But in multiple personality, the amnesia is only from the perspective of the person’s non-drinking personality. The alternate personality who drinks, and who was in control at those times, remembers everything.

Incidentally, when you interview anyone who gives a history of alcoholic blackouts, you should ask them if they’ve ever had either out-of-character behavior or amnesia when they weren’t drinking. (True alcoholic blackouts happen only during intoxication.) And when you ask, emphasize that you want to know about even small, tiny “blackouts” that happened when they weren’t drinking, since they might think that small ones don’t count. They do.

Nonalcoholic memory gaps are a primary clue to the presence of multiple personality. Of course, nonalcoholic memory gaps would be due to alternate personalities other than the one who drinks. (It is rare for a person with multiple personality to have only two personalities.)

In short, alcohol is sometimes blamed for the out-of-character behavior and/or amnesia that is really caused by unsuspected, hidden, multiple personality.