A catheter includes a distal distension balloon and circumferentially arranged motility measurement balloons proximal of the distension balloon. A manifold includes balloon ports each configured to fluidly couple to a motility measurement balloon, pressure transducer ports, and a priming port. A port selector is coupled to the manifold and movable between different positions. Each port selector position causes the manifold to establish different fluidic couplings between the respective motility balloon, pressure transducer, and priming ports. A pressure sensing device includes pressure transducers each fluidly coupled to one of the pressure transducer ports. The pressure sensing device is configured to coordinate calibration of the pressure transducers at atmospheric pressure with the port selector in a first position and motility balloon pressure measurements with the port selector in a third position. Priming of the motility measurement balloons is implemented by moving the port selector to a second position.
