New imaging methods can now directly link ongoing brain function to human behavior. This breakthrough is producing a wealth of new information about cognitive functions and should eventually uncover the roots of neurological and psychiatric diseases.

It is now possible to visualize activity in localized regions of the human brain by using techniques such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET). The value of these imaging techniques depends upon knowledge of human cognition that corresponds to the underlying physiological measurements. This knowledge must combine experimental psychology with a quantitative understanding of the computational and algorithmic aspects of brain function. Research at the McGovern Institute will therefore coordinate brain-imaging studies with studies of behavior and computational modeling.

Current imaging techniques are limited in spatial and temporal resolution. For example, the smallest spatial area of the brain that can be examined by functional magnetic resonance imaging (fMRI) is roughly a cubic millimeter, a volume that contains roughly 10^5 nerve cells! Similarly, current imaging techniques detect changes in physiological activity only over the course of a few seconds, whereas important aspects of neural processing frequently occur in milliseconds.

Greater resolution may be achieved by combining techniques such as fMRI with reporter molecules that change their properties with neural activity. Molecular probes can also be developed to signal very specific neural activities based on changes in optical properties. These and other advances might enable researchers to eventually achieve a major breakthrough in neuroscience by directly imaging the activity of single neurons. The McGovern Institute will sponsor interdisciplinary research to extend the limits of current imaging techniques by working closely with engineers and basic scientists at MIT and around the world.