Tactile self-induction of epileptiform EEG phenomena in the context of extreme somatosensory evoked potentials

This 3 year-old girl with severe psychomotor retardation and epilepsy was noticed because she clapped almost continuously. She appeared to experience this clapping as pleasurable. Whenever the child clapped her hands, the electroencephalogram (EEG) showed focal spikes. These tactile self-induced spikes corresponded with respect to latency and topography to midlatency somotosensory evoked potentials (SEPs), but had extremely large amplitudes and can thus be considered as extreme somato-sensory evoked potentials (ESEPs). The analogy of these tactile self-induced EEG spikes with self-induced seizure discharges in photosensitive epilepsy is suggested. There are arguments to hypothesize that ESEPs are more epileptogenic than simple SEPs.