How Fast Is Reflex Action?

The fastest involuntary muscular reflex in the body fires at about 13 m/s — comparable to a sparrow flying. Reflex arcs are deliberately routed through the spinal cord rather than the brain, since waiting on conscious thought would be far too slow.

Reflex arcs route through the spinal cord, not the brain — bypassing conscious thought entirely for speed.

• Same speed as a sparrow flying
• Bypasses the brain entirely for speed