Epileptiform K Complexes

ABSTRACT. The term “dyshormia” implies paroxysmal responses to arousing stimuli, either electrographically [spiky K complexes in non-rapid eye movement (NREM) sleep] or with clinical seizures (Niedermeyer 1972). It has been shown, however, that focal temporal spikes may also occur in conjunction with K complexes. Accordingly, arousal-induced spiking may occur not only in primary generalized epilepsy (PGE) but also in focal forms of epilepsy. In PGE, the dyshormia phenomenon is obligatory and a basic element. K complexes with focal spikes in temporal lobe epilepsy are rarely observed and facultative, providing evidence of the powerful “drag” of the K complexes from the midline to the area of the focal spike.