I was demonstrating spinning at a living history museum when a woman came up to see my method of spinning. After I told her about drop spindles and she figured out how they worked, she excitedly called a man over. The man had considerable vision impairment. He got to feel the spindle and the strand of spun wool, which was pretty long because I hadn't wound on, and up to the mass of fluffy BFL top. We described to him how the spindle spins in mid-air, creating twist that goes up the strand and forms yarn out of the wool.
I have heard or read that blind people can spin. I use my sight almost all the time to help me control my gauge so I don't know how well I would do.