Take my friend, Claire. She's a highly-skilled cartographer, holds down a hugely important job and happens to have had epilepsy since she was very young. She makes me laugh when she tells me of one particular kind of seizure she's experienced: basically, wandering.
I'll let her explain...
"There was a time when I was at a conference at Gatwick and walked out, though security, all in a trance. I walked along the Gatwick to London road which is rural at the Gatwick end and when I came round, thought 'Where am I!'
"There were just cars whizzing by; no houses, no people to ask - just grass, well that doesn't help much does it! All I could do was walk one way or the other and I didn't even know which way I'd come from. If there'd been houses I would probably have acted the 'lost tourist' and knocked at a door but I had to walk to the next sign. I got to a junction that said London and remembered I hadn't been in London.
"Meanwhile back at the conference they'd realised I was missing and had phoned my late father, who I'd given as next-of-kin. He was dying of cancer at the time but was calm, telling them not to worry. I eventually made my way back just by walking in the right direction. I didn't know for what reason I was going there - just hoped it would become clear when I arrived."
The episode took a total of three hours out of Claire's life: missing moments which, added to her many other walkabouts, add up to a sizeable chunk of missing time from her life. That, in itself, is an odd concept. It's also a specific example of the 'other' type of seizures, post-epileptic automatism in this case, that are rarely talked about but make a colossal impact on people's lives.