Resting-State Functional Electrical Properties Tomography (rsfEPT)

Motivation: Recent studies show task-evoked functional electrical properties tomography (fEPT) may detect neuronal activations, but the underlying neurophysiological substrates are unclear. Moreover, analysis of resting-state fEPT (rsfEPT) has not yet been reported. Goal(s): To investigate rsfEPT fluctuations to reveal/elucidate potential neurophysiological, noise and artifactual contributions. Approach: We performed independent component analysis (ICA) of rsfEPT in three healthy volunteers and compared it with ICA-based rsfMRI. We analysed power spectra of independent components (ICs) and compared rsfEPT ICs with the rsfMRI default mode network (DMN). Results: Compared with rsfMRI, rsfEPT had more ICs which had broader spectra and different spatial distributions compared with the rsfMRI DMN. Impact: We demonstrated rsfEPT for the first time using ICA. In addition to elucidating potential contributions to task-based fEPT, both neurophysiological and noisy or artifactual, this rsfEPT technique opens the possibility to reveal new conductivity-based resting-state networks in the human brain.