Answer:
The bust of Pallas that the raven perches upon represents sanity, wisdom, and scholarship. When the raven perches upon this statue of Athena, it visually represents the way the speaker's rationality is threatened by the raven's message.
The raven by Edgar Allan Poe
The raven stands as a symbol of the loss of the narrator whose heart yearns for his beloved Lenore. The raven represents evil and death. The raven is also a symbol of the narrator's grief as well as the wisdom that the narrator gains through their exchange.