ABSTRACT
Positron Emission Tomography (PET) is an imaging modality that uses radiotracers to measure receptor levels in the brain. Radiotracers are molecules that bind to a specific receptor and are labeled with a positron-emitting radionuclide, usually carbon-11 (11C) or fluorine-18 (18F). This allows investigators to quantify neurotransmitter and other related receptors in the human brain. There are radiotracers available to image a number of different brain receptors, including dopamine receptors and transporters, serotonin receptors and transporters, GABA and glutamate receptors, opioid receptors, and others. In addition to PET, Single Photon Emission Computed Tomography (SPECT) can also be used to image receptors.
