Non-invasive integrated system for brain stimulation and magnetocorticography

DESCRIPTIONprovided by applicantUnderstanding the electrophysiology of neural circuits in the human brain is critical for advancing our knowledge of human nature since fast neural communication underlies our remarkable perceptualmotorand cognitive abilitiesStudying such networks requires a method to stimulate one or more nodes of any network with precise timing and a method to accurately measure electrophysiological activity with millisecond time resolutionAt presentsingle channel transcranial magnetic stimulationTMSdevices are used to stimulate one focal region of the cortex and an array of EEG electrodes to measure the consequences of such stimulations on network functionsThis type of device can stimulate only one region at a time with a rather diffuse area of stimulation and record brain activity smeared by the intervening scalpskull and cerebral spinal fluidCSFWe propose to develop and test a novel noninvasive system with the stimulation and recording capabilities required for understanding functional roles of neural circuits in the human brain with high time resolutionIn this SBIR Fast Track projectwe will first test the basicchannel unit during Phase IIn Phase IIwe will construct achannel cryogenically cooled high density TMS coil array integrated with achannel TMS compatible atomic gradiometerAGarrayPhase IAimAConstruct achannel cryoTMS system with amm OD coil encased in a tubular miniature cryostat with acm diameter hole in the middle and an OD ofmm and a remote control positioning mechanism for radially moving the probe to touch the scalpIt will be connected to a liquid nitrogenLNreservoir via a flexible transfer tube for cooling the TMS coilAimBConstruct an axial miniature AG encased in a rod likemmprobePhase IIAimAConstruct achannel TMS coil array based on thechannel system with an automated positioning systemcooled by a closed loopLNrecyclerAimBMagVenture will construct achannel TMS stimulator specifically for this project and deliver it to Tristan for integration with the TMS systemAimCConstruct achannel AG array based on thechannel AG and a controller with a high laser pump power for shortening the recovery time after each TMS pulse to andltms We will develop techniques for mass production of these AGs using the MEMS technologyAimDDevelop the software for controlling the TMS stimulator for targeting the E field to desired locations with optimal orientationsAimEIntegrate theTMS coils andAG probes into a single systeminserting an AG probe into the middle hole of each cryostat and between the cryostats for high spatial resolution and test the functionality of the systemPhase IIAimEvaluate its capabilities onhealthy adult volunteers in a magnetic shielding enclosureusing the software capable of controlling the TMS system and measuring MEG signals in real timeWe will test if the TMS MEG system can be used to stimulate one or more nodes of a sensorimotor network and to study functional roles of each node of the network PUBLIC HEALTH RELEVANCEWe propose to develop and evaluate a novel integrated multichannel system for human functional brain mappingThis system will consist ofa novel transcranial magnetic stimulationTMSsystem based on a dense array of cryogenically cooled TMS coils andmagnetoencephalography based on a dense array of room temperature miniature atomic magnetometer probesWe will evaluate the capabilities of the multichannel TMS system in stimulating one or more nodes of any cortical neural network and the capabilities of the novel MEG system for identifying the cortical activity produced by the TMS stimulation on cortical networks with sensitivies that arehigher than existing MEG and EEG systemsThis new system will provide a novel approach for determining functional connectivity and functional roles of cortical networks in human brain in health and disease