A modelling study to inform specification and optimal electrode placement for imaging of neuronal depolarization during visual evoked responses by electrical and magnetic detection impedance tomography.

摘要: Electrical impedance tomography (EIT) has the potential to achieve non-invasive functional imaging of fast neuronal activity in human brain due opening ion channels during depolarization. Local changes resistance cerebral cortex are about 1%, but size and location recorded on scalp unknown. The purpose this work was develop an anatomically realistic finite element model adult head use it predict amplitude topography scalp, so inform specification for vivo measuring system. A detailed (FE) produced from high resolution MRI. Simulations were performed visual evoked with recording potentials by electrodes or magnetic flux density magnetoencephalography (MEG) response current injected electrodes. predicted validated recordings saline filled tanks boundary voltages measured scalp. Peak 1.03 ± 0.75 µV (0.0039 0.0034%) 27 13 fT (0.2 0.5%) respectively, which yielded estimated peak signal-to-noise ratio 4 averaging over 10 min 1 mA injection. largest occipital cortex. This modelling suggests, first time, that reproducible could be single channels, although a higher SNR would desirable accurate image production. findings suggest study is warranted order determine signal methods improve SNR, such as prolonged other processing may needed