Blackouts are periods of amnesia, caused by excessive consumption of alcohol, during which a person actively engages in behaviors but the brain is unable to create memories for what transpires. This leaves holes in a person’s memory that can range from spotty recall for the events of the previous night (known as fragmentary blackouts) to the utter absence of memory for large portions of an evening (known as en bloc blackouts).
Blackouts are very different from passing out, when a person falls asleep or is rendered unconscious from drinking too much. During blackouts, people can participate in events ranging from the mundane, like eating food, to the emotionally charged, like fights or intercourse, with little or no recall. According to Dr. Aaron White, Program Director for Underage and College Drinking Prevention Research at the National Institute of Alcohol Abuse and Alcoholism (NIAAA), “It can be quite difficult for an outside observer to tell if someone is in a blackout. The person could seem aware and articulate, but without any memory being recorded.”
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