Grant: Research Tools and Instruments - Category 1 (<$150,000)

Trans-cranial magnetic stimulation (TMS) has become one of the premier techniques for the Cognitive Neuroscientist. It complements fMRI (which correlates regions of brain activity to behavior) by allowing one to briefly and safely disrupt focal regions of brain activity and measure the changes in behavior that this causes. However, TMS is only as good as one's ability to properly aim it at the correct brain site. Originally we did this using EEG coordinates, and then using MRI coordinates. Now, we need a commercially available 'navigation system' that can pin-point TMS pulses over regions of functional activity identified in the same individual subject (using fMRI). This is now convenient, because York has purchased a 3-T fMRI that is now operational under our Vision Research Centre. (The parallel Discovery Grant proposal describes the principle applicant's previous and proposed work on MRI-guided TMS of cortical areas involved in visuospatial memory). In order to realize the power of this combined approach, we need a robust navigation system that has sufficient accuracy and precision, and is convenient to use in real-time conditions. We also need a system that can stabilize the subject and TMS coil in different configurations to obtain secure results. This proposal describes a system that will fulfill each of these requirements in the foreseeable future for my lab and for our collaborators. The research that this system will support is crucial to a basic understanding of how the brain represents and acts upon space, how different regions of the brain interact to guide behavior, and for the optimal integration of human sensorimotor systems with various technologies. Moreover, this equipment will be used in a research training program that involves students and investigators from multiple Institutions.