Blackout
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A: How does alcohol cause blackout?
B: A single drink often contains hundreds of chemical compounds. Ethanol is responsible for alcoholâs effect on the brain. Ethanol is lightweight and lipophilic, meaning its structure easily dissolves into fats, like those in the membranes of the outer blood-brain barrier. Once inside the brain, ethanolâs unique structure allows it to bind to, interact and affect many different neuronal receptors, impairing pathways that allow you to make careful decisions, control your impulses, and even manage your motor skills
A: Why do drunk people experience memory lapses?
B: The networks that control memory are especially sensitive to alcoholâs effect. But first, I want to explain how your brain works to save memory
A: Ok
B: Typically, information about your surroundings is taken in by your sensory organs and sent to the brain. Neurons transfer this information to one another via chemical messengers called neurotransmitters, which are released by one neuron and received by receptors at another. When a neurotransmitter binds to a receptor, it unlocks an internal channel, allowing small ions to flow into the cell. If enough ions enter the cell, the neuron fires sending the signal forward. Through this process, different regions of the brain can communicate with one another in milliseconds, creating our moment-to-moment understanding of the world. But ethanol interacts with receptors, making it harder for neurons to communicate
A: Why do many intoxicated people seem somewhat capable of performing basic tasks?
B: Because while compromised, the brain is still able to transfer information. In other words, brain function is highly impaired but not completely broken, but memory storage is a different story. The transfer of moment-to-moment understanding to something we can remember is thought to depend on a process called long-term potentiation, or LTP
A: How does LTP work?
B: LTP happens throughout the brain, but it is especially important in learning and memory regions like the neocortex and the hippocampus. During LTP, the firing of a neuron triggers physical changes to its structure. For example, more receptors may be moved to the cellâs surface, making the neuron more sensitive to future signaling from its neighbors. These physical changes increase the likelihood that a cell will fire again at that connection, strengthening the wiring between neurons. Through this stronger connection, itâs thought that a stable memory is formed
A: So ethanol disrupts LTP, blocking the physical changes needed for memory formation. While moment-to-moment information is encoded and understood, the storage of that information is blunted, resulting in a blackout. But if I drink a little wine, does it still cause a blackout?
B: Not all levels of drinking result in blackouts. They happen when a concentration of alcohol in the blood, or BAC, exceeds a certain level, approximately 0.16. But there is no magic number. At slightly lower BACs, brownouts, or the spotty memory of events, can occur, as some neurons continue to function properly while others fail
A: I saw some people drink a lot but they donât experience blackout. Why is that?
B: Factors like dehydration level, genetic differences, medications, and even how much youâve eaten can affect the likelihood of a blackout. Teenagers appear to be especially vulnerable due to substantial changes in brain development during those years
A: What happens if a person repeatedly over-drinking?
B: Alcoholâs short-term effects usually donât last longer than the time it takes for the body to metabolize it, or about a day. But repeatedly over-drinking can damage neurons and permanently impair memory. It can also harm other organs like the liver, which works overtime breaking down alcohol