There are many mysteries behind the science of dreams. There are also many questions about why you keep having that dream where Jeff Goldblum asks to borrow your calculator. (Why is Jeff in your middle school math class? Where did his calculator go? Why isn’t he wearing pants?) The biggest mystery about dreams, however, is why you can’t read in them.

This phenomenon goes widely unnoticed and unbelieved among the sleeping population. Of course, you’ve read a book, a clock, or a sign in your dreams before. How else would you know the way to Santa’s Sweet 16 party? Well, as it turns out, this is most likely not true. Scientists and dream experts believe that reading, writing, and most aspects of language are nearly impossible to use while dreaming.

Your brain is still relatively functional while you sleep but certain parts are far less active. Broca’s area and Wernicke’s area, for instance, two parts of the brain responsible for interpreting language, show significantly less activity while you dream. Stringing a coherent sentence together is much more difficult when your Wernicke’s area is off duty.

This doesn’t mean that dreamers can’t understand ideas; it just means that the way those ideas are interpreted is different. Most people can identify what someone is saying in their dreams, but they can’t really pinpoint the specific words. Some even describe their communication in dreams as a form of telepathy.