Gradient based emulation of neuro-electro-magnetic oscillations: A validation technique for MRI-based detection of Biomagnetism

Abstract

Spin-lock based absorption of magnetic oscillations offers potential for direct detection of electrical neuronal activity. We propose a novel versatile validation and calibration technique which paves the way for emulation and quantification of biomagnetic fields. Using ultra-weak gradient waveforms, the method mimics brain activity and thus projects artificial fields onto the tissue under investigation. The method applicable for sequence validation or signal calibration was tested in phantom and in vivo experiments with the built-in gradient system providing sinusoidal field modulations down to 1 nT. It proved to be reliable and reproducible and hence can potentially enable quantification of biomagnetic fields.