Neural control of bladder sensory nerves gives signals to the brain informing it that the bladder is full as soon as it is filled with urine. To transmit this information, the nerves make connections with other nerves in the spinal cord. In turn, the brain sends impulses back to the bladder telling it to empty its contents.
The lower urinary tract (LUT), which consists of a reservoir (the urinary bladder) and an outlet made up of the bladder neck, urethra, and urethral sphincter, is dependent on the coordinated activity of two functional units for the storage and periodic elimination of urine. Additionally, unlike many other visceral activities, which are controlled involuntarily, micturition is under voluntary control and depends on learned behavior that occurs during nervous system maturation. In order to integrate the activity of the urethral striated muscles with that of the visceral organs, the bladder, and the urethra, micturition also necessitates the integration of autonomic and somatic efferent systems.