At 06:13 PM 10/02/97 +0000, you wrote:
>Its not the brain that is slow.  It is retinal persistence that causes
>images to merge.  I recently made a light listner converting light to
>sound.  The ear can hear 50Hz mains hum for example and much above.  I have
>a 50Hz monitor and it flickers if I do not directly view it.  Does the
>retina respond slower in the center?

You missed my point, I think, if there is less retinal persistence then
you are more likely to notice flicker. The brain response is there as well
and is not independent - for example in the human eye there is less
structure for detecting moving edges than say in the frogs eye. The whole
issue is actually quite complex - and yes the retinas response is highly
non-linear - there are structures that respond better to moving edges
outside the center of vision.

Rgds

Mike