Mituru Ebe

Elimination of EKG artifacts from EEGs recorded with balanced non-cephalic reference electrode method.

The EKG artifacts contaminating EEGs recorded by the balanced non-cephalic reference electrode system were removed from EEGs by using a device composed of a one channel averager and simple hardware. This device has the following advantages to the others which have been previously proposed: (1) it is possible by averaging of a few (i.e., 5) EKG artifacts in EEG records successfully with only one channel averaged EEG derived from an earlobe; (2) the averaged EKG pattern is able to follow rapid EKG pattern change due to altered body position; (3) the possibility of being affected by another kind of artifact was decreased, because the time of averaging process to obtain averaged EKG became shorter. A remaining problem in achieving a complete removal of EKG artifacts (maximally of 100 micro V) was beat-by-beat small changes in EKG wave forms due to the respiratory cycle. Therefore, it was felt that our method was sufficiently accurate for clinical examination of EEG.

Studies of rod-process by polarization method.

Based upon differences in velocity of changes in electrical sensitivity of the eye after exposure to a flash of light, it is possible to isolate a rod-process from a mixture of cone- and rod-processes. By means of this method rod-responses to spectral lights were measured at 20° from the fovea as a function of wavelengths. The spectral distribution of rod-responses determined in this manner is found in satisfactory agreement with the scotopic visibility curve.Rod-responses to a flash of weak white light were measured at various parts of the retina. The spatial distribution of rod-responses so obtained is found to show close resemblance to the density distribution of rods in the retina, although the maximum of the former is displaced farther in the periphery beyond the maximum of the density as the intensity of the flash is reduced.