Sure biological NN are much more complicated, but basically action propagation can travel in both directions, and evolution should optimize for that.
In contrast, current ANNs are focused on unidirectional propagation, and are much worse at training from single samples - to reach abilities of biological, maybe it is worth to start thinking about multidirectional?
Neurons containing joint distribution model can do propagate conditional distributions in various direction, and it is not that difficult to represent - maybe something like that could be hidden in biological (?)
In contrast, current ANNs are focused on unidirectional propagation, and are much worse at training from single samples - to reach abilities of biological, maybe it is worth to start thinking about multidirectional?
Neurons containing joint distribution model can do propagate conditional distributions in various direction, and it is not that difficult to represent - maybe something like that could be hidden in biological (?)