Integrated magnetic probes for neuronal current imaging. – NeuroTMR

Neuronal activity is based on charge transfers, which create electric potentials and ionic currents. These currents are generating magnetic fields which are detectable. These low-frequency magnetic fields pass through biological tissues without significant distortion, thus enabling efficient, remote interaction with devices inside a biological system. Previously, we have realized the first experimental proof of concept of locally recording the activity of neuronal networks in vivo with a new type of tool based on spin electronics magnetic sensors. To realize single-event recordings at neuron scale, we need to improve the sensor sensitivity and to co-integrate the electronics with the sensor for an improved form factor and signal integrity. To achieve this, in this project, we will use very low-noise Tunnel Magneto Resistance sensor and incorporate all relevant electronics directly onto the probe. The resulting new tool will open the field of magnetophysiology to understand the mechanisms of neuronal information transmission by realizing a mapping of the ionic flows in the neuropil, including vectorial information and multi-neurons simultaneous recordings, paving the way for durable implants, possibly for brain-machine interface.