Fig. 1

Setup of the source, sensor and volume conductor models for the simulations. (A) The sensor (black dots) and medial source locations (red dots) relative to a structural scan of the example participant (grey surface). (B) The locations of 9 modelled source locations for a transverse “slice” of spinal cord, a cartoon slice of spinal cord has been superimposed to illustrate where these sources are sat. (C–G) Cartoon diagrams showing how the main conductivity boundary for each tested forward model (blue shaded area) is positioned. In addition to the main volume, sub-domains representing the lungs (green), heart (red), spinal cord (grey) and vertebrae (yellow) and depicted. Panel G also includes a transverse slice through the chest to show the locations of the conductivity boundaries in more detail.