Here, we attempted to gain more insight into KCC2's role in the seizure propagation zone in human temporal neocortex.<h4>Methods</h4>We induced network activity in postoperative acute neocortical brain slices from humans with temporal lobe epilepsy under low Mg<sup>2+</sup> conditions, with and without elevated K<sup>+</sup>, and recorded it using microelectrode arrays. The gene discussed is SLC12A5; the disease is temporal lobe epilepsy.