The conductivity of the human skull in vivo and in vitro

The conductivity of the human skull was measured in vitro and in vivo. Both methods yielded a conductivity of about 0.015 Ω/m. For the ratio of the conductivities of the brain, the skull and the scalp a value of 1:1/15:1 was found. This is consistent with the some of the reports on conductivity values found in the literature, but differs considerably from the ratio 1:1/80:1, which is commonly used in neural source localization. An explanation is provided for this discrepancy, indicating that the correct ratio is 1:1/15:1