If seizures were random processes in the brain, you might expect them to stop after an arbitrary time period, just as it stops raining as soon as the built up moisture in the clouds has depleted.
Imagine instead that rain showers always lasted exactly 10 minutes (give or take a few seconds). You would suspect that the process was deterministic. Would that help you predict rain? Not necessarily – rain initiation might still be due to other random processes, but once things get started there is a well defined sequence of events that must happen before the end of the storm.
Similarly, we found that epileptic seizures lasted for a surprisingly consistent amount of time. Some patients have two (or more) distinct groups of seizure duration, indicating two different seizure pathways.
This could be important for treating epilepsy – if a patient has different seizure mechanisms they may need to use separate drugs for each category of seizure.