Essentials: Understanding & Treating Addiction | Dr. Anna Lembke

**Andrew Huberman** (0:00)
Welcome to Huberman Lab Essentials, where we revisit past episodes for the most potent and actionable science-based tools for mental health, physical health and performance.
And now for my discussion with Dr. Anna Lembke. I and many listeners of this podcast are obsessed with dopamine. What is dopamine? And what are maybe some things about dopamine that most people don't know? And probably that I don't know either.

**Anna Lembke** (0:30)
So dopamine is a neurotransmitter, and neurotransmitters are those molecules that bridge the gap between two neurons. So they essentially allow one neuron, the presynaptic neuron, to communicate with the postsynaptic neuron. Dopamine is intimately associated with the experience of reward, but also with movement, which I think is really interesting, because movement and reward are linked, right? If you think about, you know, early humans, you had to move in order to go seek out the water or the meat or whatever it was. So dopamine is this really powerful, important molecule in the brain that helps us experience pleasure. It's not the only neurotransmitter involved in pleasure, but it's a really, really important one. And if you want to think about something that most people don't know about dopamine, which I think is really interesting, is that we are always releasing dopamine at a kind of tonic baseline rate. And it's really the deviation from that baseline, rather than like hits of dopamine in a vacuum that make a difference. So when we experience pleasure, our dopamine release goes above baseline. And likewise, dopamine can go below that tonic baseline. And then we experience a kind of pain.

**Andrew Huberman** (1:54)
Interesting. So is it fair to say that one's baseline levels of dopamine, how frequently we are releasing dopamine in the absence of some, I don't know, drug or food or experience, just sitting, being, is that associated with how happy somebody is, their kind of baseline of happiness or level of depression?

**Anna Lembke** (2:16)
There is evidence that shows that people who are depressed may indeed have lower tonic levels of dopamine. So that's a really reasonable thought. And there is some evidence to suggest that that may be true. The other thing that we know is that if we expose ourselves chronically to substances or behaviors that repeatedly released large amounts of dopamine in our brain's reward pathway, that we can change our tonic baseline and actually lower it over time as our brain tries to compensate for all of that dopamine, which is more really than we were designed to experience.

**Andrew Huberman** (3:00)
Interesting. And is it the case that our baseline levels of dopamine are set by our genetics, by our heredity?

**Anna Lembke** (3:08)
Well, I think, you know, if you think about sort of, you know, the early stages of development in infancy, certainly that is true. You're kind of, you know, born with probably whatever is your baseline level. But obviously, your experiences can have a huge impact on where your dopamine level ultimately settles out.

**Andrew Huberman** (3:28)
Do you think that's a set in terms of our parents and obviously, nature and nurture interact? But is that, is dopamine at the core of our temperament?

**Anna Lembke** (3:41)
I don't really think we know the answer to that. But I will say that people are definitely born with different temperaments. And those temperaments do affect their ability to experience joy. And, you know, we've known that for a long time and we describe that in many different ways. One of the ways that we describe that in the modern era is to use psychiatric nomenclature like this person has a disthymic temperament or, you know, this person has chronic major depressive disorder. In terms of looking specifically at who's vulnerable to addiction, that's an interesting sort of mixed bag because when you look at the research on risk factors for addiction, so what kind of temperament of a person makes them more vulnerable to addiction, you see some interesting findings, first you see that people who are more impulsive, who have a thought to do something and just do it impulsively, are people who are more vulnerable to addiction. What we now conceptualize in our current ecosystem as mental illness are actually traits that in another ecosystem might be very advantageous. They're just not advantageous right now because of the world that we live in.
And I think impulsivity is potentially one of those, right? Because we live in this world that's such a sensory rich environment, right? That we're being bombarded with all these opportunities, these sensory opportunities, and we have to constantly check ourselves. And so impulsivity is something that right now can be a difficult trait, but isn't in and of itself a bad thing.