Thirdly, K-complex are almost invariably present at the start of seizures.

Delta waves are often associated with another EEG phenomenon, the K-complex.

The K-complex was discovered in 1937 in the private laboratories of Alfred Lee Loomis.

A K-complex is an electroencephalography (EEG) waveform that occurs during stage 2 of NREM sleep.

A simplicial k-complex is a simplicial complex where the largest dimension of any simplex in equals k. For instance, a simplicial 2-complex must contain at least one triangle, and must not contain any tetrahedra or higher-dimensional simplices.