So as to define a few terms for others who may benefit from this question and answer, I need to first define the term "reader response".
Reader response is a critical approach, based upon subjective thought (influenced by ones feelings, tastes, and/or opinions), in which the reader's interpretation and analysis is more heavily considered over that of the author's intent for the work.
This being said, reader response is defined simply through how a reader interprets a text, how they feel reading a text, and what the meaning of the text is for them.
Given that the work of Edgar Allan Poe has been defined by his texts (which are filled with images of death, premature burials, and mental instabilities), Poe, himself, is renowned for the bizarre life he led which adds to the mystery and intreague of his stories.
As for his texts, Poe embedded imagery dark and mysterious characters, murderous plots, fear, revenge, and supernatural events and apparitions. Through this, Poe is able to twist his works into pieces which fill the mind with all that is morbid and grotesque.
Poe's use of setting is important for reader response. If Poe succeeds at painting a picture whihc evokes images of haunted castles, abandoned places, and darkened passageways for the reader, he has succeeded at his purpose: to frighten the reader.
Poe's use of tone is perhaps even more important than that of the setting. It is through his setting, characterizations, and plans of revenge or murder which support the tone to depict the fear-evoking and anxiety-building a reader should feel when reading Poe's works.