The primary goals of the neurophysiology Core are to develop state-of-the-art electrophysiological and optical imaging to support MR studies and to make these multi-modal methods available to collaborating Yale neuroscientists. The multi-modal methods (electrical, optical, MR) provide complementary information about brain function. While MR provides unparalleled 3D coverage of brain function it lacks the temporal resolution of electrical and optical methods. In addition optical methods can provide complementary molecular level information about ion channel or protein activity associated with cellular function. MR in parallel with electrophysiology allows the regions of activation in the MR image to be interpreted in terms of neuronal ensemble activity. Combining the three methods is being increasingly recognized as critical for obtaining a comprehensive understanding of brain function.