Ooh I see what you mean edna, it's a bit like when someone turns off a light and you still see spots. Here's a link to the game in the arcade if anyone wants to see spots before their eyes:
reaction game
The final scores don't show much info as they are displayed rounded up or down to the nearest figure, so with everyone averaging under half a second they all show as 0. Out of interest I checked the full figures in the database and it turns out you are not rubbish at all edna and all the scores are really close. The current fastest time averaged 0.21 seconds and you averaged 0.24 seconds.