Memory-loss cause #7: Concussion/head injury
Why it happens: It's little surprise that, although the brain is protected by a thick skull, brain tissue is vulnerable to trauma. Traumatic brain injury (TMI) can be caused by the brain tissue slamming into the skull itself during a fall or sharp blow, or by an object piercing the skull -- a more obvious explanation for memory loss. The force of impact can cause direct damage or bleeding that causes more widespread problems.
What else to look for:
Have the cognitive problems come on suddenly? Alzheimer's disease develops slowly, but memory loss from head trauma can trace to the single incident.
Are there other signs of brain injury? These include numbness, excessive drowsiness, severe headache, weakness in arms or limbs, dizziness, dilated pupils, and slurred speech.
Do you participate in contact sports? Sometimes athletes suffer concussions in knocks and falls they consider mundane.
Has there been a recent car, bicycle, or motorcycle accident? These are among the most common situations for head injuries, especially if the person wasn't wearing a seatbelt (car) or helmet (cycle).