Young Miles hears and finds dead man in an apartment

The episodes opens with a microwave showing the time 3:16, the same number as the Ajira flight. Miles' mother Lara is being shown an apartment by a man named Trevor. A young Miles comes to the door and asks his mom for a quarter for the vending machine. Trevor is hesitant to rent the apartment to Lara because she has a child, but Lara tells him that Miles is very quiet. Lara gives Miles a quarter and he heads out into the courtyard.

As Miles approaches the vending machine, he slows down and sees a man lying dead on a floor. He looks towards apartment #4 (one of the numbers) and goes to the door and places his hand on it. He looks down at a rabbit statue (hello white rabbit reference) and looks under it to find a key to the door. He opens the door and looks stunned.

Miles yells for his mom and she and Trevor head towards the apartment. When they enter, Miles is standing at the far side of the room. The same body that Miles saw in his head is lying on the floor. Trevor says the man's name is Mr. Vonner. Lara asks Miles what he is doing in there. Miles says "He was all alone. He's scared. His chest hurt. He kept calling out for Kimberly." Trevor says Kimberly was Mr. Vonner's wife who died last year. He asks Miles how he knows that. Miles says "I heard him. He's still talking right now." Lara says that he's dead. Miles starts screaming he can hear him and covers his ears.

So Miles' ability has been present since an early age. Why does he have this ability though? Was it caused by the island?