Re: Putting blink-cursor-mode in Options menu.

["Lennart Borgman" <lennart.borgman.073@student.lu.se>]

----- Original Message ----- 
From: "Richard Stallman" <rms@gnu.org>

>       I clearly said in previous postings
>     that the blinking cursor produced discomfort to me because of
>     neuro-physiological differences with what presumably is the majority
>     of people.
>
> I believe you.
>
> What we should do depends on how common this condition is.  What
> fraction of users react this way?  Is it 10%?  1%?  .01%?
>
> Maybe someone can find something in the user interface literature
> which reports on this.

I know nothing about this particular matter, but it may be more common than
one expects. In a well controlled study of flourescent lighting it turned
out that about 25% of the population could be sensitive to that sort of
blinking. The study results showed increased headaches, stomach problems
etc. The blinking in this case is however invisible (around 100Hz) and the
magnitude only around 50%. (High frequency flourescent lighting was used for
comparision in this double blind study. This is around 30kHz and maybe a few
% in magnitude - if I remember correctly.)

Of course blinking light has a more overall impact on your eyes and brain.
So you can not compare directly. It seemed in that case however that young
people (with maybe faster neurology) had most difficulties with the blinking
light.