From Source to Scalp

THE EEG FORWARD PROBLEM · WHY A SCALP MAP CANNOT LOCATE ITS SOURCE

A cortical current dipole spreads its potential through the head and arrives at the scalp as a broad, attenuated profile. Computing that surface pattern from a known source is the forward problem, and it is well-posed. Reversing it, recovering the source from the scalp, is the inverse problem, and it has no unique solution. The colour field is a homogeneous-medium schematic, not a solved layered model.

References: Buzsáki et al. (2012) · Hallez et al. (2007) · Grech et al. (2008)