How Your Brain’s Reward Circuits Drive Your Choices | Dr. Robert Malenka

Welcome to the Huberman Lab Podcast, where we discuss science and science-based tools for everyday life. I'm Andrew Huberman, and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. Today my guest is Dr. Robert Malenka. Dr. Robert Malenka is a professor of psychiatry and behavioral sciences at Stanford University School of Medicine. He is both a medical doctor, an MD, and a researcher, a PhD. His laboratory is famous for having discovered some of the key components allowing neuroplasticity, that is the nervous system's ability to change in response to experience. In addition, Dr. Malenka's research is considered central to the textbook knowledge about how reward systems in the brain are organized and function. Indeed, Dr. Malenka's research over the last 10 or 15 years has merged what was once two disparate fields, the first being the study of neuroplasticity, again, the nervous system's ability to change in response to experience, and the other field being the field of dopamine as it relates to pleasure and addiction. His laboratory has shown, for instance, that when we seek out particular forms of pleasure, regardless of whether or not they are healthy for us, that changes the way that our reward circuitry works, and actually changes the way that dopamine is released and how it impacts the brain. And his work has also informed how we seek out healthy pleasures, including healthy food and social connection. Today's discussion explores all of these topics and by the end of today's discussion, you will have a rich understanding of how neurochemicals like dopamine and serotonin work in parallel to reinforce, that is, to increase the probability that we will engage in certain types of thinking and behaviors. So if you are somebody interested in neuroplasticity, that is, how the nervous system can change in response to experience, and/or you are interested in reward systems, what motivates us, and what we are likely to pursue in the future given our choices of past, and if you are interested in things like social connection, and empathy, or lack thereof, today's discussion encompasses all of those topics. It is worth mentioning that Dr. Malenka is a true luminary in all of the fields I just mentioned, as well as several other fields. In fact, when you look out on the landscape of modern neuroscience, what you'll discover is that a very large percentage of the top laboratories studying neuroplasticity and reward systems and so on all stemmed from having trained in Dr. Malenka's laboratory. So it's a real honor and pleasure to be able to host him today, and I'm sure that our discussion is going to greatly enrich the way that you think about brain function, neuroplasticity, and reward. Before we begin, I'd like to emphasize that this podcast is separate from my teaching and research roles at Stanford. It is, however, part of my desire and effort to bring zero-cost-to-consumer information about science and science-related tools to the general public. In keeping with that theme, I'd like to thank the sponsors of today's podcast. Our first sponsor is ROKA. ROKA makes eyeglasses and sunglasses that are of the absolute highest quality. The company was founded by two all-American swimmers from Stanford, and everything about ROKA eyeglasses and sunglasses were designed with performance in mind. I've spent a lifetime working on the biology of the visual system, and I can tell you that your visual system has to contend with an enormous number of challenges in order for you to be able to see clearly. ROKA understands those challenges, and the biology of the visual system such that they've designed sunglasses and eyeglasses that always allow you to see with crystal clarity. Now initially, ROKA eyeglasses and sunglasses were designed for sports performance, and as a consequence, all of their glasses are designed to be very lightweight and to not slip off your face if you get sweaty. However, the design of the glasses include some that are specifically for sport and others whose aesthetic really allows you to use them for sport as well as out to dinner or to work, et cetera, and that's how I use them. If you'd like to try ROKA eyeglasses and sunglasses, you can go to roka.com, that's R-O-K-A .com, and enter the code Huberman to save 20% off your first order. Again, that's ROKA, R-O-K-A, .com and enter the code Huberman at checkout. Today's episode is also brought to us by Levels. Levels is a program that lets you see how different foods and behaviors affect your health by giving you real-time feedback on your diet using a continuous glucose monitor. One of the most important factors impacting your immediate and long-term health is the way that your body manages its blood glucose, or sometimes referred to as blood sugar, levels. To maintain energy and focus throughout the day, you want to keep your blood glucose steady without big spikes or dips. Using Levels, you can monitor how different types of foods, and different food combinations, as well as food timing, and things like exercise combine to impact your blood glucose levels. I started using Levels a little over a year ago and it gave me a lot of insight into how specific foods were spiking my blood sugar and then leaving me feeling tired for several hours afterwards, as well as how the spacing of exercise and my meals was impacting my overall energy. And in doing so, it really allowed me to optimize how I eat, what I eat, when I exercise, and so on, such that my blood glucose levels and energy levels are stable throughout the day. If you're interested in learning more about Levels and trying a continuous glucose monitor yourself, go to levels.link/huberman. Right now, Levels is offering an additional two free months of membership. Again, that's levels.link, L-I-N-K, /huberman to get two free months of membership. And now for my discussion with Dr. Robert Malenka. Dr. Malenka, Rob, welcome.