A concussion is a mild form of traumatic brain injury (TBI) that affects how your brain functions. These effects can be short-term, lasting only a few hours or a couple of days, or cause long-term problems. After juvia is told to have a concussion her personality changes and she remembers. But as this is happening she captures two more harts and it seems her short term memory won't help them win her heart but who will she fall for at the end and who will stay after brain injury.