Neuroscience Ph.D. candidate Shannon Odell takes us through exactly what’s going on in your brain as you drink caffeine. Before we get started, make sure you’re good and caffeinated so you can follow along.

Humans have been drinking the stuff for thousands of years, and it’s actually the most regularly consumed psychoactive drug in the world. It’s a psychostimulant that stimulates the central nervous system. You know, kinda like cocaine, meth, and Ritalin. But it’s not a drug of abuse since it’s only a mild stimulant.

But as you slam coffee after coffee, the drinks aren’t just sitting around in your brain. Caffeine blocks the breakdown of certain messengers in your body, mainly cAMP. Your body’s main drivers for the fight or flight response are signaled by caffeine the same way they’d be signaled by a terrifying sight or a rude comment.

You may feel ready to be the best you can be, but does coffee actually give you an edge? Well … maybe. Most studies that test caffeine’s effect on your reflexes are inconclusive. It may have neuroprotective properties, and lifetime coffee consumption may be linked to an increase in memory performance and attention in older women, but that’s a bit of a stretch, too.

Apparently it’s mostly just a delicious drink. Happy coffee drinking.

And here’s what happens to your brain when you drink that other common drug, alcohol (C2H6O):