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I Did What??? The Anatomy of a Blackout

What happened last night? If you’ve ever had to utter those words after a night on the town or had to rely on your friends to fill in the missing puzzle pieces of your limited memory reel, chances are that you’ve experienced a blackout.

And trust me… it’s not a fun feeling.

What Is a Blackout?

The National Institute on Alcohol Abuse and Alcoholism defines a blackout as “a period of amnesia during which a person actively engages in behaviors but does not create memories for these events as they transpire.”

There are two types of blackouts, but both are categorized by the amount of amnesia experienced.

The forms of blackouts are classified as:

  • Fragmentary blackouts: The most common form is the fragmentary blackout, where you can remember bits and pieces of the night out, but not all of the events that occurred. Also known as “brownouts,” memory can be triggered if someone else reminds you of the night’s events.
  • En bloc blackouts: These blackouts are much more serious and much more dangerous. They occur when memory is totally disabled, meaning it feels like large chunks of time are erased or never even happened. It’s often referred to as “time traveling,” because no matter how hard you try, you’ll never be able to recall these periods of time.

Drinking large amounts of alcohol can shut down glutamate receptors to the hippocampus, the part of your brain responsible for consolidating memories from daily life. When this mental record-keeping system is tampered with, new information—such as memories—falls into a void and is never processed. Simply put, it’s not about forgetting what happened, it’s the fact that these short-term memories were never stored in the first place. Pretty frightening, huh?

Looking for Signs

There are no definite signs to identify when or if someone is experiencing a blackout. In fact, many outsiders won’t be able to tell anything is wrong. Most of the time, you can still carry on a conversation or engage in risky behaviors, such as driving a car or having sex.

In the best-selling memoir, Blackout: Remembering the Things I Drank To Forget, Sarah Hepola even recounts a drunken night where, once emerging from a blackout, she finds herself naked in bed with a man she’s never seen before. Again, this is just one more extremely frightening result of a blackout.

So what factors increase your tendency to blackout when drinking? Experts say the most telling indicator is how quickly your blood alcohol content rises. This means that doing certain things to get drunker much faster—taking shots, skipping meals—will also make you more likely to black out.

In addition, women tend to be more susceptible to blackouts. Females have fewer enzymes in the gut to break down alcohol before it’s absorbed and they also have less water in their bodies. As a result, a larger amount of alcohol enters the brain and bloodstream, increasing the likelihood that memory-related activities will be disrupted.

And finally, just like addiction, blackouts don’t discriminate. They occur not only in alcoholics, but in social drinkers, as well. In fact, according to a Duke University survey, 51% of college students who reported consuming alcohol had also experienced at least one blackout at some point in their lives.

How to Find Help for Drug or Alcohol Misuse

If you or someone you love is struggling with substance abuse, help is available and recovery is possible. Professional treatment can start anyone battling addiction on the path to a healthier and happier life. American Addiction Centers (AAC) is a leading treatment provider and has trusted rehab programs across the U.S. Please contact us free at at any time, day or night, for helpful advice, information, or admissions. You can also check your health insurance coverage using the form below.

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