We are all walking brains.
While a lot of the schooling many of us have grown up with talks about human anatomy in sections, such as the nerves and the brain, the reality is that the nerves distributed throughout the body aren't that different from the neural networks in the brain. In fact, during the human maturation process, the neural network in the brain also produces the body's nerves and there are neurons (brain cells) distributed throughout the human body — both in tissue and at junctures in the nerve network — which is why we are able to process sensory information so rapidly.
The way it works is that these helper cells essentially work as signal amplifiers.
Due to the weak strength of the electrical signals coming from the extremities — coupled with the level of electrical resistance in the nerves themselves — without the amplifier neurons we would lose a lot of the information before it ever reached the brain and those signals that did make it, would be comparatively slow and very weak, which would make things like high-speed driving, impossible.
Another deficit humans encounter is the aging process which actually increases the resistance in the nerves as the tissues breakdown over time — which, naturally, reduces the information that is able to reach our brains.
The neurons which are distributed throughout the nervous system work as relays that take any given signal and provide it fresh strength to propel it along the nerves either to the brain or from the brain to the muscle actuators.
It's that networked system, carefully evolved over eons, that allows us to have reflexes capable of driving and the fine motor control necessary to work with the tiny nuts, bolts, and screws we inevitably lose in that special Bermuda Triangle built into each of our rides at the factory.