The original reason that the grandmother cell idea was viewed as preposterous was that even though we seem to have a lot of neurons in the brain — O(billions) — we can recognize a seemingly infinite set of objects. But, perhaps you might argue that a few billion different objects looks essentially like infinity to us. Okay, but there is still a further more troubling implication of the GC theory: If an object is represented by just one cell (as sparse as one can imagine without resorting to synapses), then we might worry that the death of a single cell can totally wipe out the knowledge about a particular object. Does this every really happen? My intuition is no but I’d love to know if there’s any applicable research to think about here.

Anyways, I should say that I think Leila and Christof are great scientists and the study itself is without a doubt very, very interesting. It’s nice to see that something like a GC theory but less extreme (ie. sparse coding) can explain this kind of high-level visual recognition. To me, it’s intriguing that the representation at this level wouldn’t be ultra-distributed.