Hard Time

Bashir makes reference to TNG: "The Wounded", as well as DS9: "Whispers" and "Tribunal". Obviously, this is another 'O'Brien Must Suffer' episode. Ira Steven Behr sums up the rationale for these episodes: "Every year, we like to drive O'Brien totally mad."

Dr. Bashir says it's impossible to erase only select incidents from O'Brien's memory without erasing his entire memory. There are previous Star Trek episodes where a person's recent memories or selective memories were erased with a device by a doctor, such as done for Tom Paris in VOY: "Ex Post Facto", and done by Dr. Crusher on TNG more than once. Also a Vulcan could have been brought in to erase that portion of O'Brien's memory with a mind-meld technique, as that had been done by Vulcans in the past, such as Spock did for Captain Kirk in TOS: "The Paradise Syndrome", intoning "Forget".