The neurophysiological features of benign partial epilepsy with rolandic spikes.

SEPs were performed in 44 children with benign partial epilepsy with rolandic spikes (BERS). High-amplitude mid- or long-latency SEPs were recorded in 17 patients (38%). These giant responses showed normal latency values but reached an exceedingly high amplitude (up to 200 microV). They showed the same reactivity characteristic of normal long-latency SEPs. In a 3-year follow-up study, the giant responses were shown to disappear in some patients and to shift from side to side in others. Our study demonstrates that giant SEPs are relatively common in BERS and give further support to the concept of a functional nature of rolandic foci.