Wearable RF-EEG Cap for closed loop TMS/fMRI/EEG Applications - Project Summary Functional MRI (fMRI) is the prevailing method for both basic research and clinical functional neuroimaging in humans. A key component behind state-of-the-art fMRI is the multichannel radio frequency (RF) receive coil technology, which enables parallel imaging acceleration for improved spatial and temporal resolution. However, these imaging coils are usually fabricated on a hard helmet-shaped plastic chassis. This constitutes a critical barrier for multimodal approaches combining fMRI with other non-invasive brain imaging and stimulation methods such as electroencephalography (EEG) and transcranial magnetic simulation (TMS). While invaluable for large-scale imaging of both superficial and deep brain structures with high resolution, fMRI is an indirect measure of neuronal activity: it assesses brain function through the measurement of hemodynamic changes driven by local neuronal activity. Therefore, research approaches that combine fMRI with TMS would greatly benefit from the capability to concurrently also record EEG to obtain a direct neurophysiological measure of the underlying electrical brain activity. Specifically, the availability of simultaneously acquired EEG data would help us to (i) address fundamental questions on the mechanisms of TMS-induced changes in network-level brain activations and (ii) enable closed loop therapeutic applications for individually tailored treatment protocols. We propose to overcome the critical technological barriers for combined non-invasive stimulation (TMS) and multimodal imaging (EEG-fMRI) by applying flexible RF coil technology. Our overarching goal is to build and test a first-of-its-kind TMS compatible integrated multimodal imaging array, a “RF-EEG cap”, to allow simultaneous fMRI and EEG acquisition concurrently with TMS. To achieve this, we will employ flexible TMS-compatible RF coil elements sewed to a specifically tailored cap directly integrated with a commercial MRI compatible EEG cap. Used in conjunction with an MRI-compatible TMS coil to modulate ongoing brain activity, the system will enable studies of causal relationships between brain regions noninvasively with unprecedented spatiotemporal resolution, thus contributing to one of the main goals of the BRAIN Initiative. The project utilizes the extensive knowledge of the team mentors and collaborators in the fields of RF coil design and TMS/multimodal imaging and the availability of MR compatible TMS and EEG systems at MGH/Martinos Center. The candidate’s goal is to achieve the skills needed to launch her independent long-term research program on developing multimodal TMS/EEG/fMRI instrumentation and applying these methods in studies on the human brain. The proposed project will complement the candidate's strong prior expertise in designing and building TMS-compatible MRI hardware. The main training elements are 1) to extend the applicant's RF engineering skills to optimize the proposed flexible RF coil technology and 2) to advance her simultaneous multimodal neuroimaging/stimulation expertise for leading projects that use EEG/fMRI/EEG to test human neuroscience hypotheses.
