As far as I know they use adult brains as models. A functional brain has "meaningful synapses", i.e. neuronal assemblies that represent a given concept, shape,

As far as I know they use adult brains as models. A functional brain has "meaningful synapses", i.e. neuronal assemblies that represent a given concept, shape, etc... . Getting these out of the box is impossible AFAIK, because of the sheer number of neurons and connections to relate to one another. Especially, since the neural code is far from being decrypted. You'd have to replicate the development process, probably starting with a model of fetal brain. Is there anyone familiar with the research around? Are these concerns baseless? If not, how are they addressed?