There is also the "person lives normal life, found to have almost no brain" phenomenon: https://www.newscientist.com/article/dn12301-man-with-tiny-brain-shocks

There is also the "person lives normal life, found to have almost no brain" phenomenon: https://www.newscientist.com/article/dn12301-man-with-tiny-brain-shocks-doctors/ https://www.newscientist.com/article/dn12301-man-with-tiny-b...