Zhadin M N, Karnup S V
Zh Vyssh Nerv Deiat Im I P Pavlova. 1977 Mar-Apr;27(2):289-96.
Spike activity of cortical units and EEG on the surface of the cortex near the microelectrode were recorded simultaneously in alert non-immobilized rabbits. The technique of synchronous summation used in the data processing has revealed a statistically significant interrelation between background spike activity of the cortical units and the surface biopotentials. A predominant tendency was revealed toward generation of a spike during the maximal surface-positive deviation of slow biopotentials. The average level of cross-correlation between the spike and slow processes in the background has a magnitude of the order of +/- 10(-2), while individual cross correlation coefficients attain the magnitude of 10-1.