The electrical signals in brain are chemical reactions, not conductivity like a metal wire. They are slow! Synaptic junctions are a huge number of indirect chemical cascades, not a direct electrical connection, they are even slower! So brain morphology and connectome has a massive impact on what can be computed. Human twitch responses are done by cerebellum, not cerebrum. It's faster, but you can't do philosophy with the cerebellum, only learn to ride a bike etc. This is the brain doing the best it for the circumstances.