R. NAQUET 639 



often found repetitive discharges on the side of the lesion and at the same time dc- 

 synchronization on the opposite side. 



Garcia-Austt. In my experience the possibihty of modifying the seizure takes 

 place within a certain range of intensity, judged by the frequency of the spikes and 

 tlie amplitude. If the spikes are not too frequent, central brain stem excitation may 

 block them, but if the seizure has a certain degree of intensity then you cannot 

 block it by reticular stimulation. I would like to ask whether you tried to develop 

 an inhibitory stimulus and if this stimulus was capable ot inhibiting the discharge. 



Naquet. In the cat we were able to block the discharge by some negative tone. 

 I did not try it on man. 



Garcia-Austt. Another point is that the patient learned to produce seizure 

 discharge, a phenomenon of which he was not conscious. Now, it is hard to con- 

 ceive learning without a certain degree of consciousness. How would you interpret 

 this contradiction if there is not an intermediate mechanism that could be activated 

 by the flicker? 



Naquet. The patients are not unconscious when we use light and during the 

 spike-and-waves discharge. They may have the discharge without any impairment 

 of consciousness. Regarding the development of inhibition, our experiments with 

 lesions in cats and some results we have in man with this type of experiment, may 

 prove that inhibition may start in the cortex rather than in some other subcortical 

 structure. 



