[pixl97]

https://en.wikipedia.org/wiki/Reflex_arc

Simple answer: No, it does not go to the brain

Detailed answer: We are complex as all hell.

>A reflex arc is a neural pathway that controls a reflex. In vertebrates, most sensory neurons do not pass directly into the brain, but synapse in the spinal cord. This allows for faster reflex actions to occur by activating spinal motor neurons without the delay of routing signals through the brain. The brain will receive the input while the reflex is being carried out and the analysis of the signal takes place after the reflex action.

[TeMPOraL]

One way of seeing a subset of reflex behavior is speculative execution - as in, you'll start executing on stimulus before the brain has a chance to evaluate it, but when it eventually does, it may cancel the reflexive action. This is absurdly efficient if your reflexes are well-calibrated.