Also take into account that relatively speaking, humans are slow creatures. You make think that you are swatting a fly quickly, but by the time your brain told your hand and wrist to begin moving, a fly sensed that change your hand and before your arm even extended, it’s wings began beating. We are so slow at processing deliberate movement, that some of our limbs evolved bypass circuits (reflexes) that allow the muscle to move without having to tell the brain first, in order to protect it from damage.
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