By the numbers
Princeton’s MRI scanner
Princeton NJ — Among the most sophisticated tools for probing the brain is the magnetic resonance imaging scanner, and Princeton is one of the few academic institutions to have its own. Located in the basement of Green Hall, the device — commonly called an MRI — is in high demand among scientists at Princeton’s Center for the Study of Brain, Mind and Behavior and constitutes the human brain imaging facility of the new Princeton Neuroscience Institute.
• The MRI provides a visual cross-section of the brain in real time, but uses a non-invasive technique that does no harm to living tissue. It has allowed campus neuroscientists to conduct a wide array of pioneering experiments, ranging from some of the most detailed studies of the brain’s visual system ever to be carried out in a human, to the first studies of characteristically human faculties such as moral reasoning and economic decision-making.
• The MRI generates a magnetic field that is about 60,000 times stronger than the Earth’s. Because of the magnet’s intense attractive force, no iron-based objects are allowed into the scanning room.
• When operating, the device requires 80 kilovolt amperes, or the amount of power used by about 1,000 household light bulbs.
• Scientists use the scanner seven days a week, from 9 a.m. to 9 p.m. on weekdays and variable hours on the weekends. As it requires from 60 to 90 minutes to scan a subject, the facility must be reserved for a minimum of two hours.
• Roughly half of a subject’s body passes into the MRI during a scan. Medical facilities usually have an MRI that can scan the entire body, but because Princeton’s device is only used to observe the brain, a subject’s legs and lower torso remain outside it.
• About 15 research groups use the scanner regularly. Though the majority are psychologists, their collaborators often include scientists from other departments, including chemistry, molecular biology, mathematics and several engineering disciplines.
• The MRI scanner, installed in November 2000, weighs approximately 4 tons and requires 335 square feet of space.
• The University’s planned new buildings to house the neuroscience institute and psychology department — to be located south of the Icahn Laboratory — are expected to include space to significantly expand the MRI facilities.
