1. Department of Biomedical Engineering, Carnegie Mellon University, 346 Hamerschlag Drive, Pittsburgh, PA 15213-3815, USA
2. Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213, USA
3. Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15213, USA
4. Department of Radiology, University of Pittsburgh, Pittsburgh, PA 15213, USA