September 14, 2022 at 11:58 am
For a good after-night blackout, the ingredient is unfortunately well known. One night (much) too much water and here is the result! But if alcohol is the trigger, what is the brain process that leads to this temporary amnesia?
Alcohol abuse is dangerous for health.
The blackout, not to be confused with the loss of consciousness at the end of the evening, defines an inability for our brain to remember the moments experienced.
Memory loss: the fault of the hippocampus?
This phenomenon is due to the impact of alcohol on the hippocampus, the seat of memory in our brain. The latter plays a key role in the chemical processes of information consolidation over the long term. This brain structure being more sensitive than others to the inhibiting effects of alcoholit is then no longer able to transform immediate memory into long-term memory. “It’s like a tape for which you have stopped pressing the record button for a while” abounds Aaron White, neuroscientist at Duke University Medical Center in Le Monde.
More specifically, the drink plays on the phenomenon of Long-Term Potentiation (LTP). It is a process by which communication between two neurons is facilitated.
More specifically, ethanol molecules disrupt the receptors to which glutamate binds, a neurotransmitter essential for neuronal connection, which slows down the transmission of information between neurons and therefore their future fixation in the form of memory. It is also impossible to recall later these memories carried away by alcohol.
The blackout, a widespread temporary amnesia
Long labeled as being the prerogative of long-term alcoholics, recent studies show that the phenomenon turns out to be much broader than it seems. In effect, 50% of people under 25 say they have experienced at least one in their lifetime.
“For a long time, we believed that only alcoholics were subject to this kind of amnesic episode” explains Professor Mickael Naassila, addiction researcher at the University of Picardy. Now we also know that blackout can happen to anyone who drinks too quickly or too much. If the regularity in consumption turns out to be indeed one of the factors of the black-out, many other phenomena come into account. such as age, gender, build.
A group of researchers from the University of Palo Alto in California published a study showing that women have amnesia while drinking on average three glasses less than men.
Sources used:
Le Monde: “alcoholic blackout”, an unknown amnesia in front of which “we are not equal”
The Conversation: when memories dissolve in alcohol
In your body: why alcohol makes you forget the end of the evening
JAMA Network : Genetic Epidemiology of Alcohol-Induced Blackouts