The most important feature of neonatal seizures is the difficulty of identifying seizures based solely on clinical manifestations even by experienced physicians (Murray et al. 2008; Aileen et al. 2009). Many physicians have probably encountered cases where it is challenging to confirm a true neonatal seizure, even after receiving a report of a “seizure” from nursing staff. On the other hand, there are cases that present only with symptoms such as apnea, which are unlikely to be seizures. Moreover, there are subclinical seizures that are not accompanied by any clinical symptoms.