Adequate Spatial Sampling

For many years, biophysical analyses have shown that information is lost unless an intersensor distance of 1 to 2 centimeters is achieved with EEG sampling (Malmivuo & Plonsey, 1995; Ryynanen et al., 2004; 2006; Srinivasan et al., 1998).

Achieving a 1 to 2 centimeters sampling density would require 500 EEG channels distributed evenly over the surface of the head.  With 256-channel sampling, dEEG now approximates adequate spatial sampling.  With EGI's medical grade EEG systems, this accuracy is now available to clinicians wherever brain monitoring is required.

Malmivuo, J. & Plonsey, R. (1995). Bioelectromagnetism. New York: Oxford University Press.

Ryynanen, O. R., Hyttinen, J. A., Laarne, P. H., & Malmivuo, J. A. (2004). Effect of electrode density and measurement noise on the spatial resolution of cortical potential distribution. IEEE Trans Biomed Eng, 51(9), 1547-1554.

Ryynanen, O. R., Hyttinen, J. A., & Malmivuo, J. A. (2006). Effect of measurement noise and electrode density on the spatial resolution of cortical potential distribution with different resistivity values for the skull. IEEE Trans Biomed Eng, 53(9), 1851-1858.

Srinivasan, R., Tucker, D. M., & Murias, M. (1998). Estimating the spatial Nyquist of the human EEG. Behavioral Research Methods, Instruments,; Computers, 30, 8-19.