“In a nutshell, serotonin gives your neurons a thick skin, so they can withstand the pace of the bristling, bustling, neural metropolis

“In a nutshell, serotonin gives your neurons a thick skin, so they can withstand the pace of the bristling, bustling, neural metropolis. And then along comes a tiny army of LSD molecules, marching out of their Trojan Horse—a small purple tablet—and they look just like serotonin molecules. If you were a receptor site, you wouldn’t be able to tell the difference. Through this insidious trickery, LSD molecules fool the receptors that normally suck up serotonin. They elbow serotonin out of the way and lodge themselves in these receptors instead. They do this in perceptual regions of the cortex, such as the occipital and temporal lobes, in charge of seeing and hearing, and in more cognitive zones, such as the prefrontal cortex, where conscious judgments take place. They do it in brain-stem nuclei that send their messages throughout the brain and body, felt as arousal and alertness. And once they’ve taken up their positions, Troy begins to fall. Not through force, as with the devastating blows of alcohol and dextromethorphan, but through passivity. Once encamped in their serotonin receptors, LSD molecules simply remain passive. They don’t inhibit, they don’t soothe, they don’t regulate, or filter, or modulate. They sit back with evil little grins and say, “It’s showtime! You just go ahead and fire as much as you like. You’re going to pick up a lot of channels you never got before. So have fun. And call me in about eight hours when my shift is over.”

― Marc Lewis, Memoirs of an Addicted Brain: A Neuroscientist Examines his Former Life on Drugs