Concerned by the growing numbers of people using stimulant medications such as methylphenidate (MP)—either legally or illegally—to improve attention and focus, researchers used positron emission tomography (PET) imaging with the radiotracer fluorodeoxyglucose (FDG) to assess the effects of the drug on brain function in the normal human brain.

Abuse of psychostimulants such as amphetamine remains a serious public health concern. Amphetamines mediate their behavioral effects by stimulating dopaminergic signaling throughout reward circuits of the brain.