In this short film, you'll learn about how the brain and bladder connect and work together to control bladder emptying. The bladder stores urine until you are ready to empty it to urinate. The bladder send signals along the spinal cord to your brain that it's filling up. This signals the feeling that you need to urinate when everything is working normally.

You can then decide when to empty your bladder. The bladder receives signals as it fills with urine to indicate the need to urinate. When the bladder is about halfway full, around 250 milliliters, you get the first sensation you need to urinate. As the bladder continues to fill, the sensation becomes stronger and the urgency to urinate increases.

The bladder muscles relax as your bladder fills, but contract when you urinate. The sphincter muscle controls the flow of urine out of the bladder, which squeezes the urethra shut as the bladder fills and relaxes as the bladder is empty. How often you need to urinate depends on several things, such as your fluid intake, how much urine you produce, and how much urine your bladder comfortably holds. So that's a short explanation of the connection between your brain and bladder and how they work together when it comes to emptying your bladder.