It is important that your thesis refers to the fact that as the story is a first-person account of events, the audience has only information from a clearly deranges source. The narrator’s words, action and diction all conspire to present him as an irrational, and therefore untrustworthy, narrator.
An exploration of the bizarre movements of the narrator would help to indicate his heightened consciousness and awareness, and may be called upon to support a claim that he is so precise in his actions and observations that his account is intensely precise. A possible question for debate and analysis could be the following:
‘The story of “The Tell Tale Heart" requires the audience to trust the account of an unreliable narrator.’ How far do you believe this to be the case?’
Like all the Poe-characters, the narrator in 'The Tell-Tale Heart' is also a hardened obsessional neurotic. What Freud defined as 'Repetition Compulsion' in Beyond The Pleasure Principle can be used as an accurate theoretical idea to explain his mindscape. He is obsessed with something horrendous, beyond the 'Pleasure Principle' and keeps repeating it compulsively throgh the course of his life. Narrators of 'Berenice' and 'The Tell-Tale Heart' are examples of this mental state with a situation of disclosure at the end. The narrator in this story is mortified by the sound of the heartbeats of his old and lousy master and goes on to strangle him to death just because he cannot tolerate the sound. But as always in Poe, the horror repressed will always stage a deadlier return. Since the story is written from his perspective, one can understand the psychic autonomy of this 'low' and 'grating' sound and the man's paranoid fixation with it is also revealed. The disclosure at the end is also brought about by his persistent fear-psychosis.