What is the theme of "The Yellow Wallpaper" by Charlotte Perkins Gilman? Does it have a motif of creativity vs. insanity?

"The Yellow Wallpaper" by Charlotte Perkins Gilman is a quasi-autobiographical story about a rest cure prescribed for what was diagnosed in her period as a "nervous disorder". The protagonist of the story is portrayed as undergoing such a cure and going slowly insane over the course of the story. As we read it, though, we begin to understand that the so-called cure resembles something like the solitary confinement of prisoners or sensory deprivation, something we now understand as more likely to result in than to cure mental disorders.
The main theme of the story is the tension between the active creative role of the artist or writer and the passivity expected and limited opportunities available for women in Gilman's period. As the protagonist is confined, her creativity manifests itself in creating a story born in hallucination rather than one crafted in words. Thus we are led to understand that the creative imagination when thwarted in its need to create may escape into insanity. 
Shakespeare famously stated 

... the poet’s pen ... gives to airy nothing
A local habitation and a name.

Gilman argues that the creative urge, when deprived of its outlet in artistic creation, will turn to madness.