He has a big seizure ... tonic clonic aka grand mal.
It was likely triggered by stress ... he had one of his most stressful weeks ... plus dehydration ... plus the flickering of the light in our basement when we turned it on.
We had gone down there after the ride Rowan mentions to build my new rowing machine. Flicked on the light ... and that was apparently the "last straw".
I am just glad I was here with him when it happened.

Machka tells me I basically collapsed, and was transferred to a 20-hour stay in the same neurological ward at the hospital where I was very first admitted last year. Much of what we have been able to configure is that I didn't drink during the ride and that contributed largely to setting off the problems. The CT scan at the hospital also demonstrated to me that the brain injury I sustained last year is somewhat permanent, and recovery has been based on being able to work to other undamaged parts of my brain to return to some level of normality.

My basic message these days is don't ride a bike without a helmet... or work by operating high-ish equipment without similar head protection.