Recently, satisfying slime videos have become very popular on Snapchat stories, Instagram, and Youtube. The real question is, why are they so entertaining?

Studies say that watching videos like these are a calming technique for anyone. The oddly satisfying videos appear to tap into a subconscious urge toward what psychologists call a “just right” feeling. Teens are usually very stressed, and watching strange, mesmerizing videos of the gooey substance seems create a calming effect.

These videos feature hands mixing glitter, glue and other materials in a play-dough like substance called slime. There are now nearly 900k posts tagged as #oddlysatisfying on Instagram, but not just in slime-making. Other odd substances began to appear such as kinetic sand slicing, soap cutting, paint mixing, and sponges.

If you feel like just watching them isn’t enough, and you’d like to do it yourself, you just need all the right ingredients, utensils, and a camera.