Positron emission tomography

Positron emission tomography (PET), technique used to study brain activity. A person undergoing a PET scan is injected with a glucose solution containing low-level radioactive particles that produce positrons, electrically charged particles that help produce gamma rays. The person places his or her head inside a ring containing sensors that measure gamma ray signals from the brain, and these signals are translated by colors onto a screen. Scientists reading the screen can interpret the colors in a way that measures brain activity.

See also: Brain.