Healthy Brain, Happy Life (31 page)

However, there are specific features of exercise that suggest that it would have a similarly positive effect during withdrawal from a much wider range of drugs. Specifically, all the data showing that exercise can decrease signs of depression and stress. Stress is a key trigger for relapse in recovering addicts, and as discussed, exercise works to decrease stress in myriad ways. With less stress comes less depression.

So, it is clear that exercise could be useful during the initiation, escalation, and recovery/withdrawal of addiction. All the neuroscience data suggest that this is because exercise uses many of the same pathways and activates the same reward centers of the brain as drugs, without a real addiction developing.

TAKE-AWAYS: BRAIN AREAS IMPORTANT FOR THE WANTING PART OF REWARD

•  Drugs become addictive by overactivating the reward system that puts into motion immediate and very long-lasting genetic and anatomical changes in the reward circuits if the drug use continues.

•  Because exercise activates the same reward circuits as addictive drugs it can help decrease the chances that drug use is initiated, it can curb the escalation of drug use if it has already started, and it can curb cravings in some cases and decrease stress levels that can decrease the chances of relapse.

•  Exercise can become addictive itself and caution must be used when trying to design a program to replace drug addiction. It is important to monitor and minimize the shift to an exercise addiction.

ACTIVATING MY REWARD SYSTEM BY GIVING BACK

Life outside the lab was now just plain fun for me, with more and more social time and a growing circle of friends. We spent time eating, drinking, going to movies, and seeing shows together in the city. While I loved every minute of my new social life (I was finally starting to make up for my hermitlike early years at NYU), I found some of my greatest pleasures in activities in which I could give something back to the world. Since the summer of 2009 I have been teaching a free weekly and year-round exercise class for the NYU students, faculty, and staff. It’s also free and open to anyone outside of NYU. At first the class was a great way to practice leading an exercise class right before the start of my “Can Exercise Change Your Brain?” class. But it became so much fun that I just kept on doing it. Many students in my “Can Exercise Change Your Brain?” class continued taking my weekly exercise class long after the semester was over, and I’ve met many students from all over the school whom I would have never met otherwise.

Some of my most memorable experiences from my weekly exercise class have come from the transformations that I have seen in my students. When I first started teaching the class, Pascale, a very bright, gregarious postdoctoral fellow in my department at NYU, was the only guy who came to class regularly. This did not bother him at all. Week after week, he took his place in the center of the front row and did the class with gusto. One morning, we both got on the elevator in our building at NYU, and Pascale asked if he could tell me something.

“Of course,” I said.

He said, “You saved my life!”

I thought he was joking around. Or perhaps my lab had loaned him something he needed for his experiments. He went on to explain that when he started my classes he weighed close to fifty pounds more than he did now. Only then did I realize that the sweat shirt and pants he was wearing were hanging off him like a scarecrow. Then he showed me his old NYU ID, and the difference hit me like a ton of bricks. His face looked so much thinner and angular (in a healthy way) now! I don’t know how I could have missed it. He went on to explain that he was in bad shape when he started taking class, in part because his work and school schedule meant he had not been exercising at all. He told me it was my regular class, together with the motivation of seeing one of the professors in his department teaching it each week, that kicked him into gear to exercise and start losing weight himself. He supplemented his classes with me with other exercises at home, but he credited my class with jump-starting his progress.

Pascale not only has kept the weight off but is keeping fit in new and innovative ways. He recently told me he had just gotten a treadmill for his desk at work so he could walk and work at the same time. He invited me to his office to check it out, and it was impressive. A beautiful shiny new treadmill that he had set up in front of his desk computer so he could keep walking during the many hours a day spent at his desk working, reading, and typing. For the last several years I have used a standing desk while I work to help decrease the inevitable slouching that happens when I type while sitting down, but I never considered adding a treadmill to my setup. Pascale has definitely inspired me!

My weekly exercise class is not the only way I give back. In fact, the reason I am familiar with the great work at the Odyssey House is that I organized a group of several exercise instructors to provide six months of free exercise classes for Odyssey House clients at the main Harlem branch. I loved getting to know my O House regulars, and it truly warmed my heart to see how grateful they were for the classes and all the teachers who donated their time.

Of course, I had to look into what was happening to my brain when I felt happy about giving back to the community. There are findings to explain the brain areas involved in those warm and fuzzy feelings that I always get when I’m giving back. Studies done at the University of Oregon measured brain activity in people given the opportunity to voluntarily donate to a charity. Many previous studies had shown that giving subjects money activates the brain’s reward circuit. That makes sense! Who doesn’t like getting money? What this study showed was surprising: When people voluntarily gave money to a charity on their own, it activated the same reward circuit as getting the money themselves. This is neuroscientific proof that giving is as rewarding as getting. In other words, generosity is rewarding and good for the brain. From a very personal perspective, I wholeheartedly agree with this finding. But it’s not just blatant donation that I find rewarding. That very first time I stepped up and started teaching my fellow anatomy students what I knew about the structure of the liver, I remember getting a little jolt of pleasure. I thought it was pleasure from the act of teaching, but it was really pleasure from the act of giving. I think most teachers, and certainly all great teachers, are great because they are doing something that they love doing. Teaching is what is activating their reward systems, and it’s the altruistic nature of the job that seems to be the key.

BRAIN HACKS: ALTRUISM

Try some of these four-minute Brain Hacks to activate your reward system through altruism.

•  Pay the toll for the person behind you.

•  Help a stranger in the street.

•  Smile and greet someone you don’t know in the street.

•  Be kind to someone you dislike (extra points for this one!).

•  Pick up trash on the street or on the beach.

•  Tape your extra spare change to the jungle gym in the park for kids to find.

•  Write a handwritten thank-you note to someone.

•  Share your knowledge with someone.

LOVE, ROMANCE, AND THE REWARD SYSTEM

On the dating front, I was convinced that all the exciting new and sometimes altruistic adventures in my social life would soon attract equally exciting adventures in my romantic life. As I’ve mentioned, I am a firm believer in the idea that you attract into your life the kind of person that you are. I loved my life now, the person I was becoming and all the new friendships I had formed. I was ready and willing to start my next romantic relationship, and before too long someone new came into my life.

His name was Michael and we were introduced by a mutual friend.

The very first thing I noticed about Michael was his positive energy. He had a kinetic personality but also made you feel like you were the center of the universe when he was talking to you. He was funny and very sweet. The first time we met for a casual lunch, all I remember was how easy it was to talk to him. We chatted all through the meal and all the way out the door after lunch was over. When we finally reached that point where we had to walk in opposite directions, I remember thinking he actually looked sad to say good-bye to me!

It was the most endearing first-date moment that I have ever had.

For the next date we planned to meet up for a drink but I was (conveniently) starving so we went out for dinner instead. Despite his energy, Michael was quite shy at first, which was great because it provided a calm atmosphere as we got to know each other. We seemed to have lots of important things in common. We were both passionate about our jobs, mine in science and his in government, we both loved living in New York and had both spent time living in Washington, D.C. We also seemed to have the same family and life values. I particularly admired his close and loving relationship with his extended family. And he could really make me laugh.

Talk about activating the reward centers in the brain! I had this image of the dopamine neurons in my VTA firing like mad. In fact this image I had of my own VTA activation was accurate. Neuroscientists have started to study the parts of the brain activated in the early stages of intense romantic love, just like what I was experiencing, and it turns out that studies done in England, the United States, and China give surprisingly consistent results. All of these studies showed that the parts of the brain that become activated when subjects are looking at a picture of their beloved, compared to the activation seen when subjects are looking at a picture of an acquaintance, include the VTA and the caudate nucleus (also a major target of the VTA’s projections). All studies agree that VTA activation represents the high reward value associated with seeing your sweetheart when you are in the throes of early romantic love. The caudate nucleus, like the VTA, has been associated with reward and motivation. For example, another study reported that when a monetary reward was predictable (in other words, if you find yourself a rigged slot machine that gives a payout every time you play), this same region of the caudate nucleus gets activated. So things that are a sure bet for high levels of reward activate the caudate nucleus. In addition to observing the consistent areas of activation when someone is looking at a photo of her beloved, researchers noted a consistent inhibition of the amygdala. The idea is that fear, processed by the amygdala, is decreased during periods of intense love. Based on my own personal experience, I would agree with this interpretation. These findings suggest that during the early stages of intense romantic love, your dopamine reward and motivation systems are working in overdrive and your fear response is inhibited. No wonder I felt so good!