ANNs aren't supposed to model biological neurons, they're more inspired by them. We actually know a great deal about how real neurons work, although the emergent effects keep us from learning much about the brain as a whole.
But modeling biological neurons is expensive; they're far more complex than a logistic function. Just modeling a worm is taking them an entire cluster, and they appear to be using a pretty simple model (the Hodgkin–Huxley equations way back from 1952). I don't think we'll ever simulate real neurons to detect cat photos. Instead, modeling entire brains might allow us to see how learning happens, which could be simplified into new algorithms for machine learning.
But modeling biological neurons is expensive; they're far more complex than a logistic function. Just modeling a worm is taking them an entire cluster, and they appear to be using a pretty simple model (the Hodgkin–Huxley equations way back from 1952). I don't think we'll ever simulate real neurons to detect cat photos. Instead, modeling entire brains might allow us to see how learning happens, which could be simplified into new algorithms for machine learning.