字幕列表 影片播放 列印英文字幕 Part 3: The Reward Circuit In this graphic you can see the limbic system in dark color and the cerebral cortex on the outside, which is very large in humans and much smaller in monkeys and rats and other animals. You can think of cerebral cortex as the rational, logical brain, sort of like Spock on Star Trek. It's not emotional, it's the planning, thinking part of our brain, which comes up with clever ideas. Now, the cerebral cortex understands the consequences of our actions; the limbic system does not. Like car engines, all have the same basic design, so do all limbic systems. Whether it belongs to a rat, cat, dog, or us. Now, whether it's hunger, mothering, mating or sexual desire, or even addiction, the same brain chemicals and structures do the same jobs in all mammals. You see, scientists aren't studying rat brains to trying to figure out how to help rats. No, they're studying them to help us with our addictions and other reasons. The study is useful to us because limbic systems are so similar in all mammals. It's important to remember that the chemical balance of our limbic system shapes how we see the world, shapes our mood. If our limbic brain is out of balance, so is our decision making. At its most basic, the limbic system is all about avoiding pain and repeating pleasure. You see, survival depends on the avoidance of pain, both physical and emotional and the repetition of pleasure, hot stove = bad, ice cream = good, mommy = good, snake = bad. Porn = good? You get the idea. Now, you're looking at the center of the brain, sliced down in the middle and you can see there is this pretty small area called reward circuit. Sometimes you also hear the term reward center and you can see that it actually goes from the limbic system up to the rational brain. This is so important. We're going to be spending most of our time talking about this circuit. You see, this is where you experience all desire and most pleasures such as sex and orgasm. It's also where you decide what you don't like and what you do like and that's why it's pretty important. It's small, but in essence, it's running the show. You never make a decision without consulting your reward circuit. If you're addicted to anything, here's where it happened. The reward circuitry is activated whenever we engage in behaviors that further our survival or more importantly, the survival of our genes. The rule is this: To get motivated, you must be rewarded. So this circuit gives you feelings of pleasure and also the motivation to seek out pleasure. It drives you to eat, engaged in sex, take risks and bond. It's where you fall in love with your spouse and with your children and your parents. It also gets activated when your team wins, or you feel like an alpha male, or you're bungee jumping. The more exciting the experience, the stronger this reward circuitry is activated. But, keep in mind that it's also activated for simple pleasures like watching a beautiful sunset, or walk in the woods, or even a smile from a girlfriend. Chemicals turned on and off certain parts of the brain. For the reward circuitry, it's dopamine. It's the main chemical of a group called neurotransmitters. They turn the reward circuitry on. The reward circuitry is the engine, it truly is, and dopamine is the gas. If you really like high calorie foods, that maybe because you actually get a bigger blast of dopamine for it than you do for low calorie foods. You crave them more because their register is more rewarding. That's why you choose chocolate cake over brussel sprouts. It has been programmed: “Give me high calories!” Think about sugar. A sugar buzz is dopamine acting on the reward circuitry. It's not the sugar in your blood acting on the brain. Now, excluding drugs like meth or cocaine, orgasm is the biggest blast of dopamine. Dopamine has lots of nick names: The craving neurochemical, the “I got to have it no matter what” neurochemical. You see, it's behind all motivation to do anything. You're not craving ice cream or sex with a porn star. No, you're actually craving more stimulation of your reward circuitry. You don't want to win the lotto; you want to activate your reward circuitry. The bigger surge of dopamine in response to something, the more you want it. Here's a question. Why don't those hedge fund billionaires retire? They certainly don't need any more money. Yes, they want more dopamine in the form of winning at the stock market game. Donate and help us make Medical Education Universal, Free, State of the Art and Available to Every Human Being. For more such videos, join our Facebook group. Let's make Medical Education Universal, Free, State of the Art and Available to Every Human Being to enable the best medical facilities for everyone.