Interleaflet electrophoresis. Anionic phospholipids are electrostatically driven across the bilayer boundary at the periphery of a pore in the direction of the anode. This results in PS "flopping" (externalization) at the anode and "flipping" at the cathode (any PS present on the outer face of the membrane in the vicinity of a pore will be driven inward to the cytoplasmic leaflet of the bilayer).
Vernier et al. BMC Cell Biology 2006 7:37 doi:10.1186/1471-2121-7-37