Can you draw parallels with other texts by Poe to "The Raven"?
One of the many distinguishing marks of Poe's fiction is the way that he effectively uses an unreliable narrator to inject a profound feeling of unease in the reader. His first person narratives in poems such as "The Raven" and in short stories such as "The Tell-Tale Heart" and "The Black Cat" are so effective because they introduce us to first person narrators who, as the narrative progresses, we come to believe as being thoroughly unreliable.
This I would argue is the central link between "The Raven" and other Poe texts, such as those mentioned above. Another good one to look at might be "The Cask of Amontillado." All are linked through the way that unreliable narrators are used to tell us the story and the way in which their characters are presented as suffering from madness, insanity and/or psychological pressures that make their account of the story partial and incomplete.
If we examine the narrator of "The Raven" to look at this in more detail, we can see that the narrator is physically, emotionally and psychologically exhausted. Note the description we are given at the beginning of the text:
Once upon a midnight dreary, while I pondered weak and weary,
Over many a quaint and curious volume of forgotten lore,
While I nodded, nearly napping...
The narrator himself confesses that he is "weak and weary," straining himself to study late at night when he should really be in bed. In addition, the second stanza shows us how he is "vainly" trying to alleviate his grief for "Lenore." We are introduced to a man whose obsession with this woman has driven him to the edge of reason. What happens, therefore, and the sinister introduction of the raven, makes us see the event as showing more about his state of mind than anything else. This is the unifying factor that links this poem to so much of Poe's other works.
While much of Poe's writing can be compared to each other very easily, based upon his signature styles and texts (as pointed out by accessteacher), another parallel to "The Raven" can be seen in "Annabel Lee." Poe wrote both "The Raven" and "Annabel Lee" as poems used to help him get over the fact that his wife, and cousin, Virgina, was dying of consumption (or tuberculosis). "The Raven" was a poem which Poe used to reflect the fact that Virgina was not going to get better (as seen by the repetition of "nevermore"). "Annabel Lee" was a poem which spoke to the loss of Virgina. It was this poem which allowed Poe to move on (as much as he could) after the death of his wife.