The narrator undergoes a mental conversion that leads her to the revelation about freedom. She fixates on the wallpaper and projects her issues onto this symbol. Her obsession gives the walls additional meaning, and she becomes the “creeping woman.”
Detailed answer:
The Yellow Wallpaper tells a story about a mentally unstable woman in an abusive marriage. The protagonist’s husband confines her to the premises of the home. Due to the mental and physical limitations, Jane starts to fixate on the yellow wallpaper. It becomes vital in her life as she uncovers more of its meaning.
At the start of the story, the character is disturbed by the peculiar pattern of the wallpaper. Then Jane sees a creeping female behind the design. Although the protagonist is disgusted by her at first, the meaning of “creeping” changes. Jane recognizes that she reflects the woman imprisoned by the walls and creeping on other people’s lives.
In the beginning, the word “yellow” represents the character’s mental illness. Then the meaning changes. The protagonist gets obsessed with the wallpaper. Jane identifies with the girl imprisoned by the walls. She starts to define “yellow” as the color of confinement. So the words’ meaning change along with the ill state of mind. It leads the character to the revelation about her figural imprisonment.