Does scp-173 account for sight problems?

My question is that if someone who was completely blind were to stare at where scp-173 was, and they knew it was there, would scp-173 snap their neck? And if not, what if the blind person didn't know it was there? Also, if someone couldn't make out that they were looking at scp-173, because of cataracts or just poor vision, would it move?