Basis and use of a true monopolar derivation: the neo-electroencephalography (N.E.E.G.)

A new method of monopolar recording is presented. This true monopolar derivation is based on a computer-reconstituted signals method: use of a reference electrode obtained by interconnecting two electrodes placed one on either side of the neck to form a common pole; detection by Fourier analysis of the various frequencies from 0 to 16 Hz in 1/4 Hz steps; continuous comparison of phase for each activity per 1/4 Hz between the signal PF left - Reference Neck (RC) and O right - Reference Neck (RC) in order to see whether the reference electrode is active or not; automatic subtraction of the value of the reference electrode from the value of all other reference channels if the reference electrode is active. The technique is available for routine purposes. The results are easy to read and provide more precise data as well as new parameters which could prove useful in current clinical practice. The first electroclinical correlations covered frequency, location of potential gradients and phase relations established for 40 adult normal subjects with a reading identified as normal, and for 60 adult pathological subjects with a reading also identified as normal. Clear differences appeared between these two types of supposedly normal readings.