字幕表 動画を再生する 英語字幕をプリント Hey there! Welcome to Life Noggin. That… Oh… That subscribe button is not supposed to do that. Hey guys, the subscribe button is not supposed to do that! Who could forget their first time biting into a pizza bagel? The taste of that delicious morsel will stay in my memory forever. But what will happen to that memory after I die? It may help to first understand what memories are. Your brain contains around 100 billion neurons that communicate with each other across gaps called synapses using proteins and chemicals called neurotransmitters. A memory is formed when certain proteins, like AKT and CaMKII, strengthen the synaptic connections. The formation of long-term memories takes time and occurs over stages - a process known as memory consolidation. Once complete, the neurons involved in the original experience become a fixed combination to help you remember the entire event - from sound to taste. But over time, memories can alter or fade. Scientists have found that memories are malleable and can change during recall or from outside suggestion. And as we age, certain types of memories, like the association between two things or the recollection of specific details, diminish. Researchers think this may be due to the fact that the hippocampus shrinks as we age, which is the region of the brain that stores these types of memories. Compared to other organs, your brain requires much more energy to function. That is why it is the first organ to fail or become irreversibly injured when the heart stops pumping, such as during cardiac arrest. The first part of the brain to go is the hippocampus, which plays a big role in memory storage. If heart function isn't restored, the entire brain will shut down in just 4 or 5 minutes. But just 3 minutes without blood flow leads to brain injury that will progressively get worse and eventually become irreversible even if the person is resuscitated or brought back to life. That is why many survivors of cardiac arrest suffer from memory loss even years after the event. In a 2009 study of cardiac arrest survivors treated with hypothermia to protect brain function, one-third had moderate to severe memory difficulties and nearly half had mildly affected long-term memory measured by the Rivermead Behavioural Memory Test. But a number of cardiac arrest patients have reported memories of near death experiences that occurred after their heart had stopped beating and they were considered clinically dead. In one study, 40% reported having awareness during this time, and in another, 10% reported memories of this period. This may be caused by a surge in electrical activity in the brain after death. A 2013 study in rats found that within the first 30 seconds after death by induced cardiac arrest, they displayed neural patterns similar to a highly aroused brain. Though this doesn't necessarily mean the same thing occurs in humans, and many neuroscientists believe that near death experiences are born from the stress of the cardiac arrest and are memories of the events before death - not after. So, most likely, after we die and our brain shuts down for good, our memories will simply fade away like a deleted computer file. Anyway, I hope my last memories are of all the pizza bagels I've eaten. No need to think about bad things! Yay! So, do you have an earliest memory that you can remember? Maybe a favorite memory of yours? If you're comfortable with sharing it, let me know in the comment section below! Curious to know what would happen if you never forgot anything? Check out this video! Hyperthymesia is a rare mental state or neurological condition where a person has a very detailed autobiographical memory. Basically, they remember a lot about their past! As always my name is Blocko! This has been Life Noggin! Don't forget to keep on thinking.