At the University of Minnesota Medical School, Minneapolis, Kamil Ugurbil, PhD, is the leader of a team developing methods to increase the sensitivity and specificity of functional MRI at ultrahigh field strengths. Because these levels are still experimental in humans, more work is needed to determine how the added capabilities of high field strength can be set free from the drawbacks that now accompany them. For example, physiological noise may increase at the same rate as signal strength, perhaps even becoming strong enough, in some situations, to erase the advantages of high field strength. The first goal of this investigation is, therefore, to reduce noise and similar technical problems. The researchers will then determine whether sensitivity and specificity depend on field strength and how resolution (spatial and temporal) is affected.
High-resolution functional MRI of human brain regions (as opposed to the entire brain) will be used to improve understanding of high-field signal fluctuations and the blood oxygenation level dependent response at ultrahigh magnetic fields. The availability of a 7T whole body imager makes this work possible, bringing research on this topic out of the animal realm for the first time. It will eventually become possible to study neuronal function at the submillimeter scale.