Peri-ictal yawning lateralizes the seizure onset zone to the nondominant hemisphere in patients with temporal lobe epilepsy.

The main aim of this retrospective study was to investigate the incidence and lateralizing value of peri-ictal yawning in patients with temporal lobe epilepsy (TLE) who underwent successful surgery for epilepsy (Engel class I outcome at the 2-year follow-up visit). We reviewed a total of 97 patients (59 men and 38 women). Fifty-three patients had TLE arising from the nondominant temporal lobe, and 44 had TLE arising from the dominant temporal lobe. In total, we reviewed 380 seizures. Of those, 202 seizures arose from the nondominant temporal lobe and 178 from the dominant one. Peri-ictal yawning was observed in 4 of 97 patients (4.1%) and in 7 of 380 seizures (1.8%), in the postictal period in all cases. Peri-ictal yawning occurred only in patients with right-sided, nondominant TLE. It may have a lateralizing value.