These parasympathetic neurons make the rectum contract and the internal anal sphincter relax.

这些副交感神经元可以使直肠收缩，并使肛门内括约肌松弛。

Symptoms of cauda equina include decreased bowel and bladder control due to a decreased tone of anal sphincters and muscle wall of the bladder and decreased sexual function.

马尾神经综合征的症状，包括排便和膀胱控制能力；这是由于肛门括约肌和膀胱壁肌肉张力下降引起的，以及性功能下降。

Meanwhile, signals are sent to the brainstem and thalamus, and when these decide the right moment has come, they allow the external anal sphincter to relax - and feces goes, hopefully, into the toilet bowl.

直肠发出的信号同时也发送到了脑干和丘脑；当它们认定“时机成熟”时，便会下达指令使肛门外括约肌松弛；粪便就能——不出意外的话——顺利排入马桶。