You did not add any text, therefore it is unsolvable. It would be helpful to add the story and scene so that people who want to help you have something so work with.
Barney is a dinosaur from our imagination
Answer: The art of secret writing is called a cypher.
If we stare at a pattern for a sufficient amount of time, our brains will cause the pattern to spontaneously reorganize itself.
Many psychologists believed that humans' pattern recognition abilities exist to aid us in our survival. This ability make us able to quickly identify possible danger/occurrences from several sign, which will help us to produce faster fight or flight response.