In the yellow wallpaper, the theme of deterioration is caused by the theme of isolation and vice versa. The woman in the Yellow Wallpaper is diagnosed with a nervous condition. She sees the "best" doctor around and is sent to bed rest. Now, with the jist of the plot out of the way, let's delve into the explanation of the themes. The woman is fully isolated from everybody and everything in an attic of an old family home. She has windows that face every direction, but they are barred. The only thing in the room is a bed, a desk, and the walls covered in yellow wallpaper. This is where her isolation causes her deterioration. She becomes so lonely, that she starts to see women in the wallpaper. Now, if she really saw women or if it was her shadow from the sun and the moon is up to debate, but she started to go a little bit psycho. She used to write everyday, but eventually that was taken away from her. With no outlet to express her emotions and no way to occupy her mind, the only thing of sensation to her was the yellow wallpaper. As her mind deteriorated more and more, she became even more sick in the head. Her loneliness, so extreme, caused her to start talking to the women in the walls. On the last day, she had finally cracked. She began ripping and tearing at the wallpaper to set the women free. Her isolation and deterioration created figments of her imagination that influenced her to move all the furniture in front of the door and to rip and shred until no wallpaper was left. As her husband finally barged in, the deterioration of her mind was fully evident. Because the narrator describes her as creeping over her husband's fainted body.
Bonus opinion:
In the yellow wallpaper, it seems that the narrator's name isn't really mentioned. Now I think because of the deterioration of the woman's mind, she thinks that because she released the woman in the wallpaper, she became that woman. The woman in the wallpaper is actually the one talking to John, and refers to the woman that was sick as Jane.
Bonus opinion:
In the yellow wallpaper, it seems that the narrator's name isn't really mentioned. Now I think because of the deterioration of the woman's mind, she thinks that because she released the woman in the wallpaper, she became that woman. The woman in the wallpaper is actually the one talking to John, and refers to the woman that was sick as Jane.