Low Field NMR as a Tool for Neuronal Current Detection: A Feasibility Study in a Phantom
The detection of neuronal currents (NC) may foster the understanding of the flow of information in the brain. Existing methods of NC detection like electro- and magnetoencephalography (EEG/MEG) are limited by the ambiguity of the inverse problem, while imaging methods like fMRI monitor secondary effects (e.g., blood oxygenation changes). On the other hand, attempts to directly detect NC in high field NMR techniques by a local shift of the 1H resonance frequency have yielded controversial results. In magnetic fields around 1 microTesla, the relative contribution of the biomagnetic field generated by neuronal currents is orders of magnitude higher than in conventional high fields. This may make the situation much more favourable.