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In addition to standard pattern-reversal VEPs, the motion-onset VEPs were examined in 50 patients with acute unilateral retrobulbar neuritis (RN) and in 187 patients with possible or definite multiple sclerosis (MS). In MS patients (without sign or history of RN), the results of both types of VEPs correlated only partially. 26.2% of them displayed changes only in the motion-onset VEPs having the pattern-reversal VEPs completely normal. That is why we suppose that the magnocellular system (tested by motion-onset VEPs) can be affected by demyelination separately. In 28 patients with "pure" RN (without any other sign indicating demyelination disease) the always abnormal pattern-reversal VEPs were accompanied by delayed motion-onset VEPs in only 28.6% of patients. In contrast, much higher rate--68.2%--of delayed motion-onset VEPs was found in the 22 RN patients simultaneously suspected of MS These results indicate that RN affects predominantly the parvocellular visual system (tested by reversal VEPs). Distinct latency changes of the motion-onset VEP's in RN patients seem to signal a linkage between RN and demyelination.

The technique of investigating evoked visual potentials (EVP) is resumed within the context of electrophysiological methods as applied in optic neuritis. Several typical courses of the disease are case-reported in this account. In conclusion, authors recommend further on EVP implications due to its objectivity, non-invasiveness and time-sparing with a possible automated evaluation.

Stimulation by means of moving the structure in the visual field is used to produce visual evoked responses (VER) only rarely. The authors attempted to verify the fact how VER to the movement depended on some stimulation parameters and to compare them with VER to the most frequently used stimulation method, i. e. reversal. Horizontally moving black and white vertical stripes were used with special frequency 2.3 cycles/deg on the screen. It was found that at least 3s interval between two stimuli (between the end of the preceding and onset of the following movements) was necessary and sufficient period of the moving was about 100 ms. Resultant VER are then a reaction on the onset of the movement and are characterized mostly only by marked negative peak with latency being 140 to 200 ms. Opposite to reversal VER, those to the onset of the movement were obtained just in 87.5% of the persons examined (n = 40), in five cases, however, the response to the onset of the motion was higher than that to reversal VER amplitudes were in the latter case highest in the unipolar lead from the right occipital region with the rate of the structure movement being 42 to 84 mm/s.