The poem "I felt a Funeral in my Brain" by Emily Dickinson is in the form of an allegory, a tale with a literal level and one or more symbolic levels; the funeral is an exterior structure that gives coherence to the speaker's mental state. Because the loss of the speaker's mind is simultaneous and tortured, the funeral provides a symbol for what transpires in the speaker's mind, a symbol that does not reveal the inner thoughts of the speaker, thus allowing her feelings some privacy.
Without the structure of the funeral, the reader might have no idea what happens with the speaker's mind. The images in the second and third stanzas clearly convey the speaker's growing sense of despair, and the images in the fourth stanza convey her sense of isolation. Finally, when a "Plank in Reason, broke" the reader understands that the speaker has lost her mind.
The poem is in the form not so much of a dream but rather of a nightmare. A bad dream alone could not include the details Dickinson puts into this poem. The conclusion of the vision in the last stanza is diffcult to follow, for the speaker imagines that she has been walking on the floor of reason, but then a plank breaks; she plunges downward and has "Finished knowing – then -". It would appear that the speaker’s hurt is so great that she has no interest in any further kinds of experience from which she could learn.