This study is researching how the anorectal area works in healthy adults. The anorectal area is where the end of the digestive system is, near the anus and rectum. The study will compare two types of tools called catheters, which help measure how this area functions. One catheter is air charged, and the other is solid state. Catheters are small tubes inserted into the body to help doctors see how things work inside. The study's goal is to find normal values for these measurements using a special method called the IAPWG protocol and the London classification.

To participate, you must be 18-65 years old, willing to sign a consent form, and follow study instructions. People with certain digestive problems, like IBS (Irritable Bowel Syndrome) or frequent diarrhea, can't join. Also, if you've had certain surgeries or injuries in the pelvic area, or are pregnant, you're not eligible.

• Participants must attend all study visits.
• No compensation is mentioned for participants.
• Risks include discomfort from catheter insertion.