Which condition features sudden onset of memory loss for new and recent information with both anterograde and retrograde amnesia lasting 3-24 hours, but has no stroke risk and no confabulation?

• A. Basilar artery TIA
• B. Transient ischemic attack
• C. Posterior circulation
• D. Transient global amnesia

Answer: (D)

Transient global amnesia presents with a sudden inability to form new memories (anterograde amnesia) and loss of access to recent past memories (retrograde amnesia) that lasts about 3–24 hours. During the episode the person is typically awake and alert but repetitive, asking the same questions as they try to learn new information, and there are no other focal neurological deficits. Importantly, memory for distant past and personal identity remains intact after the episode, and there is no confabulation. This full, isolated amnestic syndrome without other cognitive loss or behavioral changes is the hallmark.

This pattern distinguishes it from transient ischemic attacks or basilar artery–related events, where focal neurological symptoms (such as weakness, aphasia, visual changes, ataxia, or cranial nerve findings) accompany or precede symptoms. A marked memory disorder alone is not the typical feature of a TIA or posterior-circulation event, and confabulation is not expected in transient global amnesia, helping set it apart from conditions like Korsakoff syndrome.