本文主要内容：What Are Brain Waves?Hi, this is Kate from MinuteEarth.Animals move in all kinds of ways, but one thing all that motion …
What Are Brain Waves? 来自译匠 00:00 02:09
What Are Brain Waves?
Hi, this is Kate from MinuteEarth.
Animals move in all kinds of ways, but one thing all that motion has in common is rhythm. So it’s not really that surprising that the simple neural circuits driving these motions are basically little rhythm machines, with electrical patterns that give rise to coordinated motion. Perhaps more surprising is that crazy, complex neural circuits that aren’t dedicated to movement also have rhythm: All over our brains all the time, millions of neurons are syncing up – sometimes for just a fraction of a second – and generating electrical ups and downs that we can record as brain waves.
In healthy brains, these waves are really consistent – for instance, during normal waking activity, your brain produces a pattern called the beta rhythm, and, in deepest sleep, it generates a slower delta rhythm. In unhealthy brains, on the other hand, we see abnormal brain waves, which suggests that the rhythms do something important. The question is, what?
One of brainwaves’ roles seems to have to do with long-term memory. During one stage of sleep, short, powerful rhythms deep in the brain trigger the same sequences of neurons that were active before sleep, creating lasting connections between them. We’ve found that, without these rhythms, certain kinds of memories can’t form.
We have lots of other ideas about what exactly brain waves do – from holding information like phone numbers in our minds to dictating whether we’re even conscious. Or maybe the rhythms in our brains are even more important than that – maybe their main function is to keep time for the brain – to keep all the parts sufficiently synchronized so that they can work together. Synchrony in the brain not only enables groups of neurons to fire together and send a strong, clear signal from one part of the brain to another, it tunes different parts of the brain in to the same frequencies, coordinating the signals between them. In some ways, it’s crazy to think that the incredible things our brains do rely on repeating, yet fleeting patterns of electrical activity. But, on the other hand, generating rhythms is sort of what nervous systems evolved to do in the first place – we really can’t get anywhere without them.