Final answer:
Loss of memory for personal information and past events is known as retrograde amnesia, where one cannot recall past episodic memories due to brain trauma, unlike anterograde amnesia which affects new memories.
Step-by-step explanation:
Loss of memory for personal information and past events is known as retrograde amnesia. This condition involves an inability to recall episodic memories due to brain trauma. Imagine the profound impact of not recognizing your own family and having no recollection of your past, as can happen in severe cases. Unlike anterograde amnesia, where new information cannot be retained, retrograde amnesia affects memories formed before the injury. Studies, such as those on individuals like K.C. and H.M., reveal the fragility of our memory systems and the various ways they can fail.