rmorey parent
Yes. The C. Elegans brain (~300 neurons) was the first organism to be completely mapped to a connectome (the map of all connections). The first complete connectome of any centralized brain, the fruit fly, is about to be completed by the Flywire project (https://home.flywire.ai/) ~100,000 neurons and ~70,000,000 synapses. We have just a little idea how it works ;)
A bit of extrapolation might suggested we could map out the connectome of a human brain in 40-50 years. Not that I’d suggest a linear extrapolation from two data points…