What Is a MRI Scan?

Magnetic Resonance Imaging (MRI) is a special type of procedure that allows a doctor to see what is happening inside your child's body. Unlike X-rays, the MRI scanner uses a magnetic field and radio waves to produce very clear and detailed pictures of parts of the body, such as the head, heart, chest, abdomen, pelvis, spine and extremities. MRI gathers soft tissue images and is used to evaluate function and structure of organs and to distinguish normal, healthy tissue from tissues that may need to be studied for disease.

Position Emission Tomography (PET) measures emissions from radioactively-labeled chemicals that have been injected into the bloodstream, and uses the data to produce images of the distribution of the chemicals in the body.
In drug abuse research, PET is being used for a variety of reasons including: to identify the brain sites where drugs and naturally occurring neurotransmitters act; to show how quickly drugs reach and activate receptors; to determine how long drugs occupy these receptors; and to find out how long they take to leave the brain. PET is also being used to show brain changes following chronic drug abuse, during withdrawal from drug use, and during the experience of drug craving. In addition, PET can be used to assess the effects of pharmacological and behavioral therapies for drug addiction on the brain.

What is MEG?


Marker coils placed on volunteer's head

Magnetoencephalography (MEG) is a non-invasive neurophysiological technique that measures the magnetic fields generated by neuronal activity of the brain. The spatial distributions of the magnetic fields are analyzed to localize the sources of the activity within the brain, and the locations of the sources are superimposed on anatomical images, such as those obtained through MRI, to provide information about both the structure and function of the brain.