Apparently only a certain percent of the population gets that Wasabi burn and not all experience it the same way.
For me when it kicks in, i get what feels like a little warning shock, that is immediately followed by what feels like someone running an electric current all throughout my brain. I literally feel like its a rolling current as i feel it move around and i am reacting the entire time.
It is very similar, in a way to the brain freeze I sometimes get from biting into something cold, but the sensation is different as the freeze feels like just that. Cold or a freezing moving across the brain where this feels like electricity.
And while I hate brain freeze, I enjoy wasabi burn.