Bladder filling attenuates spinal cord nociceptive reflexes in humans.

•The effect of bladder filling on the nociceptive withdrawal reflex (NWR) was evaluated in healthy subjects to examine the viscerosomatic interaction between bladder afferents and somatic nociception.•The NWR was reduced in both upper and lower limbs during bladder filling which strongly indicates that bladder control and nociception share common modulatory descending pathways.•The effect of bladder filling on the NWR may represent a useful tool to investigate interactions between the neural pathways controlling the bladder and pain.