Parameters of spikes in human epilepsy.

The parameters of 600 spikes were studied in 100 epileptic patients. Spikes were subdivided morphologically into: monophasic spikes, diphasic spikes, spike-slow wave complexes, polyspike-slow wave complexes and spike followed by spike. The following parameters were analyzed: polarity, amplitude, duration and sequence, 88% of spikes were negative. 98% of spikes raised 30% above the background activity. Spike duration varied, the shortest spike had a 9 msec duration. The range of duration varied from 9 to 200 msec with a mean of 45.06. 75% of spikes were followed by a deflection lasting from 130 to 200 msec. No evidence was found in our study for the differentiation of sharp waves from spikes.