NIDA for Teens: The Science Behind Drug Abuse
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Brain Reward System

So... Why Do People Like Drugs?

Is there something magical about drugs and alcohol with us humans? So what's our fascination and why do some of us like them so much?! Actually, before we try and answer that one, let me just say: we are not alone. Some of the drugs we use, abuse, and become addicted to today were actually "discovered" by animals first.

For example, you know why we have coffee today? Well, the "legend of the dancing goats" says that coffee beans were first discovered in a field in Ethiopia by a goat herder who noticed that his goats were acting weird sometimes, running around and dancing wildly. He couldn't figure out why and so decided to study them. He saw them eating small red berries on a certain shrub found in the area—turns out they were coffee plants. After eating the berries with the coffee beans inside, the goats started their "dancing." Legend also has it that the goat herder also started eating the berries and dancing with them!

Photo of a cat with a chicken hat on.

Plenty of similar stories and observations have been made of other animals that seem to get "high" from naturally occurring drugs or fermented fruits. Cats are attracted to the valerian plant and to catnip, which seems to give them extreme pleasure. In parts of Africa, the marula fruit ripens, and animals—from monkeys to elephants—are attracted to the overripe and fermenting fruits that make them act "funny." Birds have been seen sitting on smoking tree trunks after bush fires and seem to be intoxicated—they get dizzy and fall off of the smoldering trunk only to get up and do it over and over.

Back to our question…so why do we (or at least some of us) and our animal counterparts like these natural-occurring substances and synthetic or man-made drugs? The answer is simple…blame it on our brains! We have evolved a brain that allows us to see, hear, taste, move, think, etc., and also to repeat things that feel good. That happens because a part of our brain sends out feel-good signals when we do something we enjoy, like eating good food, playing a video game, kicking a goal in soccer, listening to our favorite music, or going upside-down on a roller coaster. The system that says to us: "hey, that was good, do it again!" is called the "reward system".

Turns out that alcohol and drugs affect this system really well; they are effective at going right to our brain's "reward system" and putting it into high gear. This very effective stimulation of the reward system is why many people can become addicted to drugs, since feeling good is what drives much of our behavior. Drugs, in a sense, trick the system that has evolved for helping us in our world and instead can turn our world upside down.

As a scientist and Division Director at NIDA, I am committed to learning more about how drugs exert their effects in the brain so that we can come up with better ways to prevent young people from getting "tricked" by drugs and sliding into addiction without even realizing it.

Photo of John Frascella: Director of NIDA's Division of Clinical Neuroscience and Behavioral Research.

As Director of NIDA's Division of Clinical Neuroscience and Behavioral Research, Dr. Joe Frascella heads up a program that supports studies in humans to advance our understanding of brain and behavior in drug abuse and addiction. Studies are mainly on neuroscience, adolescent development, and treatment, with a goal of translating research results into real-world use.

Goat

Word of the Day: Euphoria

Euphoria: A feeling of well-being or elation.

Euphoria is that excitement you get from getting a perfect score on a test, or attention from someone you have a crush on. It can come from a roller coaster ride or as the rush from a physical activity like downhill skiing, especially the first time. These feelings of euphoria are all healthy and natural.

What's not healthy or natural is taking drugs to feel "euphoric." Drugs of abuse artificially produce euphoria by manipulating your brain chemistry to make it seem that something exciting is happening. To get this feeling again, you may choose to use the drugs again-and again. And that can lead to craving and addiction.

Over time, the brain needs more of the drug to get the same feelings of pleasure. Why? The drug causes surges, like waves, of the brain chemical dopamine, which initially produce the euphoria. After repeated hits, though, the brain adjusts to this higher level of dopamine by making less of it and by reducing the number of receptors that can receive and transmit the signals it sends. Pretty soon, the drug abuser is taking the drug just to bring the dopamine functions back up to normal and to avoid the horrible craving that compels them to seek and use drugs even when their lives and health are falling apart. That is really the essence of addiction.

People jumping in the air.

But the good news is that natural, healthy experiences of euphoria don't wreck the brain's chemistry. So think about what you do in life that makes you feel good. Spending time with friends, playing with your dog, doing sports, seeing a good movie? Any of these activities can create a natural euphoria by triggering the brain's reward system the way it was meant to work.

So don't let drugs fool your brain, and then wreck it.

image of Euphoria

The Different Angles of Addiction

You may think you know what addiction is—lots of people have many different opinions about addiction and different ways of defining it. Here are some myths you may have heard:

  • Getting over addiction to drugs is a choice.
  • In order for treatment to work, the person has to hit “rock bottom.”
  • People have to choose to get treatment or it won’t be effective, such as when a judge sends a person to treatment facility instead of jail.

The truth is that addiction is a complex brain disease that scientists are still figuring out. For instance, one person may use a drug once or many times and nothing bad happens, while others may overdose with the first use. Some people use drugs regularly and never become addicted, while others try drugs once or twice and do become addicted. There is no way of knowing in advance how a person may react to these dangerous substances. Whether or how quickly addiction takes hold in individuals depends on many factors, including:

  • Genes: Research shows that some people’s genes may leave them more susceptible to addiction than other people’s.
  • Environment: Kids who are exposed to drug use in their families or neighborhoods are at greater risk of engaging in drug abuse themselves.
  • Age at first use: The younger a person uses drugs, the more vulnerable he or she is to addiction in adulthood. Since the brain continues to develop well into a person’s twenties, using drugs in the teen years can set a person up for later drug problems.

What scientists know for sure is that many drugs “turn on” the brain’s reward circuit, which is part of the limbic system. The person then learns to associate the drug with pleasure and starts to crave it more and more, leading to compulsive drug use and often to addiction. In an addicted person, the brain changes in ways that cause compulsive drug seeking and use, despite negative consequences, so even if they want to quit, they can’t without treatment and support. That’s why addiction is considered a brain disease. Other activities in life also activate the brain’s reward circuit and can cause “driven” behaviors, such as compulsive overeating or video game playing. However, scientists are still trying to figure out why this happens in non-drug contexts—it may be connected to dopamine levels in the brain. Learn more about the science behind drug addiction by visiting http://nida.nih.gov/scienceofaddiction/.

Electric human brain.

Addicted to French Fries: Is Food a Drug?

According to the American Heart Association, about one in three kids and teens in the United States is overweight or obese. Obesity can lead to chronic health problems like heart disease, diabetes, and high blood pressure. Obesity can even shorten your life. You probably already heard this in the news. But, did you know that a diet high in saturated fats, refined sugars, corn syrup, and carbohydrates literally tricks our brains into craving more unhealthy stuff? Brains React to Food Most people don’t just consume food for “fuel” or energy. Most of us enjoy eating, especially our favorite foods. Science backs this up: Consuming tasty foods can satisfy the natural brain reward system, releasing the chemical dopamine in the brain to add to overall feelings of contentment and satisfaction. This is good for our survival since we have to eat to survive. Overeating is different, but is also based in the brain. Scientists now understand that, for a growing number of people, certain foods trick the brain into wanting more. Pizza, French fries, chocolate, and colas are high on the list of foods that trigger dopamine. In this way, food causes reactions in the brain similar to those caused by some drugs, like cocaine, methamphetamine, and marijuana, which also affect dopamine levels and lead to compulsive drug seeking and use. According to NIDA Director Dr. Nora D. Volkow, “We are finding tremendous overlap between drugs in the brain and food in the brain.” Steps You Can Take It’s important to balance your diet with healthy choices and right-sized portions to ensure you get all the nutrition you need to be healthy. Here are a few tips from Michelle Obama’s Let’s Move! Campaign:
  • Try new fruits and veggies. Add variety to your meals to make eating healthier, fun, and interesting.
  • Drink smart. Skip soda and other drinks flavored with sugar or high-fructose corn syrup. Choose water—make it more exciting by adding a splash of lemon or a few mint leaves.
  • Move every day. Walk or bike to your destination. Turn off the TV and go outside.
Now you tell us: What do you do to eat well, keep fit, and stay healthy? French fries

Chasing the Runner's High

Dr. Nora Volkow, Director of NIDA, is an avid runner—6 miles a day!

We all know the benefits of physical activity on the body, but as a neuroscientist, Dr. Volkow is also interested in how exercise helps the brain.

Working your body can definitely make you feel good—but can you really get a “high” without drugs?

Doing exercise like running actually stimulates the brain's reward system and releases the same feel-good brain chemicals that drugs do. The best part of “getting high” through exercise is that you avoid the negative health effects of drugs, while also making your body stronger.

What causes this natural high?  Here are a couple theories from research:

Theory 1: Endorphins and Dopamine

The body produces its own kind of opioids—chemicals closely related to the drugs morphine or heroin—called endorphins. Endorphins are produced when we feel excitement or love, or when we eat tasty food. The brain also produces endorphins during intense workouts.

The release of endorphins stimulates the brain's reward system to release dopamine—the brain’s #1 feel-good chemical. Increased dopamine in the brain causes the euphoria people get from drugs and may explain the runner’s high too.

Theory 2: Endocannabinoids

Other research suggests that a different class of chemicals, called cannabinoids, are also released by exercise and may contribute to the runner’s high.

Your body actually makes cannabinoids—called endocannabinoids—that act on the same brain receptors as the THC in marijuana. It’s no surprise then that cannabinoids are associated with the pleasant sensation, reduced anxiety, and pain reduction that marijuana can bring.

The runner’s high might even help people who are addicted to drugs. NIDA is supporting research to find out how exercise and the release of those feel-good brain chemicals might help prevent substance abuse, or even encourage people who do drugs to replace one habit with another—in a good way.

So, does knowing that exercise can make you feel happy make you want to pop in your earbuds and take a run??

Girl Running