Recently, a number of studies have shown that EEG recordings also carry important information minutes prior to the seizure onset to distinguish between
preictal and interictal states [3-15].
After training, the classifier should be able to classify and estimate the
preictal phase.
Although, compared to interictal spikes, HFOs were found to show a higher level of correlation with seizures and expose a more stable localisation, assessed ictally versus interictally [17], and their suitability as a predictive marker in the
preictal period could not be confirmed [18].
Epileptic seizures have four different states: the
preictal state, which is a state that appears before the seizure begins, the ictal state that begins with the onset of the seizure and ends with an attack, the postictal state that starts after ictal state, and interictal state that starts after the postictal state of 1st seizure and ends before the start of
preictal state of consecutive seizure.
EEG signals are divided into
preictal, ictal, and postictal sessions accordingly.
Rubboli, "Permutation entropy to detect vigilance changes and
preictal states from scalp EEG in epileptic patients--a preliminary study," Neurological Sciences, vol.
Using 5 Hz trains of repetitive TMS, the impaired homeostatic plasticity has been reported in individuals with episodic migraine during the
preictal and postictal stages of the migraine cycle [12].
Hence, the transition from
preictal to ictal state for an epileptic seizure contains a gradual change from a chaotic to ordered wave forms.
Three minutes
preictal and 10 min interictal ECoG as recorded in 39 channels in the SOZ and 256 channels in the NSOZ were analyzed.
EMU nurses also help to prevent
preictal (before the seizure), intraictal (during a seizure), and postictal (after a seizure) complications.
Also, spatiotemporal changes in
preictal spike activity in human temporal lobe epilepsy [2] revealed that the degree of bilateral interdependence in medial temporal lobe spike activity increased prior to onset of a seizure, thus indicating that spikes may herald the interictal to ictal transition.
applied PE to detect vigilance changes and the
preictal phase from scalp EEG in three epileptic patients [35].