rationalskepticism.org

Witticism wrote:

Federico wrote:... while reasonable animal lovers would agree they have no judicial nor philosophical rights since they have no responsibilities.

Many humans have "no responsibilities".

Should we use them as experimental subjects

No, because they are humans, and -- under our present code of moral responsibility -- even if incapacitated or brain dead or in any way incapable of performing his duties a human remains human and will not become a vegetable or an animal.
Under our present moral code humans don't eat humans or experiment with them, like the Nazis did while operating under a different (im)moral code.