One of the oldest psychedelics meets modern brain imaging

For millennia, people have used the psychedelic mescaline as a spiritual and religious tool.

Mescaline is a naturally occurring chemical found in cacti, mainly peyote cacti, that are located in the Southwest United States and Mexico.

The drug has been used for 5,700 years, according to archaeological evidence, making it one of the oldest hallucinogens. ...