**4.1 EEG characteristics, frequency**

GPDs are symmetric, bilateral, repetitive discharges with regular morphology and a frontal or occipital predominance; they show the same morphology and in general the same interdischarge interval (quasi-periodic in more than 50%); slowing of the delta or theta range, frequently a background suppression of cortical activity accompagny GPDs (**Figure 8**). Their occurrence with LPDs and BIPDs in the same patient is not rare [26]. GPDs are frequently encountered in comatose patients (>55%) and very early during cEEG Monitoring and are observed in 5–10% during cEEG [26].
