No one knows yet how big the leap needs to be, but the most amazing thing about ANN's is that the feature layers a CNN arrives at may functionally resemble some of those found in the visual cortex:

"The oft-cited resemblance of the imagery to LSD- and psilocybin-induced hallucinations is suggestive of a functional resemblance between artificial neural networks and particular layers of the visual cortex, a matter which merits further study." [0]

Also see "How brains learn to see" from Pawan Sinha [1].

[0] https://en.wikipedia.org/wiki/DeepDream

[1] http://www.ted.com/talks/pawan_sinha_on_how_brains_learn_to_...