MAGNETOMETRY OF EVOKED FIELDS FROM HUMAN PERIPHERAL-NERVE, BRACHIAL-PLEXUS AND PRIMARY SOMATOSENSORY CORTEX USING A LIQUID-NITROGEN COOLED SUPERCONDUCTING QUANTUM INTERFERENCE DEVICE

Superconducting Quantum Interference Devices (SQUIDs) can be used to d etect neuromagnetic fields evoked in the peripheral and central nervou s system. Up to now, such measurements had to be based on SQUIDs with a low critical temperature (T-c) requiring liquid helium cooling. Rece nt improvements in high-T-c SQUID technology relying on liquid nitroge n cooling led to a significant reduction in the system's noise level. Here, first high-T-c recordings of weak neuromagnetic fields are demon strated. In particular, along the entire somatosensory afferent pathwa y including peripheral nerves, brachial plexus and primary somatosenso ry neocortex evoked neuromagnetic activities were detected using conve ntional recording parameters for bandwidth and number of averages. Thi s opens up a wide perspective for cost-effective high-T-c magnetometry in clinical neuroscience.