Your mind is able to fill in missing details by matching them to existing information. It also cross-references and bounces between linked associations. This priming effect even works when you are not consciously aware of it. For instance, you can break an object or obscure part of it, and your brain can still recognize the object.
Be aware that seemingly subtle influences matter. If your senses perceive it, your mind is processing it. A slight change in input can have a notable influence on the outcome.