What happens when you smoke
The system that answers what happens to you
▶ Play this chapter The script
Every line as it is spoken in the film, in order.
So what actually happens when you smoke? First, one thing about your own cannabinoids. They work differently from almost every other messenger in your brain.
Most of those messengers are made ahead of time and kept in tiny packets at the tips of nerve cells. Dopamine, serotonin, glutamate. When a signal arrives, out they go.
Your cannabinoids aren't kept in packets. A cell makes them when something happens, cuts them from its own membrane, uses them right there, and breaks them down in moments.
So what makes a cell create them? Things that happen to you. In 2012, seventy-one adults gave a speech to a panel of strangers. Right afterwards, the anandamide in their blood had gone up.
Think about the feeling you had in your body the last time you were really scared. Your body made some of these keys right then.
In rats, stress makes these keys in the midbrain, and they dull pain. Block the lock there, and that pain relief disappears.
In rats that go without food, they rise in the parts of the brain that drive eating.
After a long run, they rise in your blood.
And when an old fear needs to fade, mice make more of them in the amygdala.
Each time, your body is answering something that just happened. The answer is made right where it's needed, and it's gone when the moment passes.
THC doesn't wait for a question. It comes in through your blood and turns locks all over your brain at once, whether anything happened or not. Your enzymes can't cut it, so it lasts two to three hours.
That's why being high feels the way it does. Where the locks are packed, things shift. In the cerebellum and the movement centers, coordination slips. In the hippocampus, short-term memory slips. If you've ever felt music land in your chest, or laughed your balls off uncontrollably at an inside joke with your BFF, or learned a profound insight, you've felt this system working.
But it isn't just memory slipping. Many people feel more in touch with the world around them. Music, food and touch feel more intense. In mice, CB1 even makes sweet taste stronger.
And the munchies? Remember the bulb that reads smells. In hungry mice, CB1 receptors there make food smell stronger, so they eat more. Cannabis turns up the same switch.
That's the high. THC gives your body's answer without a question, all over your brain, and for hours.
So the plant works through a system you were born with.
Sources
Every claim in this chapter with its grade: E established · M emerging (one or two studies, or animals only) · F framework.
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