His Utsusemi shadows are actual clones of himself, all capable of doing Mijin Gakure. In other words, be careful of his Shadow-Clone Jutsu! Believe it!
Eidolic vision is the ancient term; Eidetic is what the term became with the movement from qualitative to quantitative. Eidetic vision includes a special type of persistent afterimage, which has conscious qualities. This is all beyond neurology. It is an ability to process or reshape remembered forms and images. Memory is a reconnection with real things _ with eidetic or eidolic images. A similar concept, using different terminology, is developed in the book Scientology 8-8008 by L. Ron Hubbard.)
Well, the shadow image part is correct...but this concept can be traced back to Plato...who definitely pre-dates Naruto. XD
It starts as one, however after so long it duplicates itself, Kage bunshin no jutsu style. I think only one of them has the ability though so destroying that one should stop anymore from spawning. Anyone that can confirm this I'm sure would be muchly appreciated.