A Better Brain Scanner

Continued from page 1

Siemens is now working on a commercial version of the 32-channel array developed at MGH, which is expected to be on the market later this year. The imaging device, now being tested by some of Siemens's customers, "increases spatial or temporal resolution," says Jeffrey Bundy, vice president of the MR division at Siemens Medical Solutions, headquartered in Malvern, PA.

The device is likely to have important applications in functional magnetic resonance imaging (fMRI), a variation of standard MRI that tracks blood flow in the brain as an indirect measure of activity. The technique is often used to locate the parts of the brain that control specific functions, such as speech and movement. The first clinical application for the device will likely be fMRI for neurosurgery planning, says Bundy. "Surgeons want to know where speech and motor areas are when they take a tumor out--the more precise, the better."

The instrument could also impact our basic understanding of the brain. "The spatial resolution of fMRI is somewhat limited," says Gabrieli. "We've hit the wall on a lot of scientific questions." With higher-resolution images, scientists could try to determine neurological basis of various aspects of cognitive function. Gabrieli, for example, says that he'd like to figure out if different parts of the amygdala--a small structure deep in the brain that plays a key role in emotion--regulate different emotions, such as fear and joy.

While Siemens is putting the finishing touches on the 32-channel array, Wald and his colleague Graham Wiggins, also at MGH, are already developing new scanners with even more channels, including 96-channel and 128-channel arrays. "These are the highest-resolution brain images being taken today," says Wald.