If the brain has already stored someone’s face and name, why do we still end up remembering one and not the other? This is because the brain has something of a twotier memory system at work when it comes to retrieving memories, and this gives rise to a common yet infuriating sensation: recognising someone, but not being able to remember how or why, or what their name is. This happens because the brain differentiates between familiarity and recall. To clarify, familiarity (or recognition) is wh