Final answer:
Retrograde Amnesia is the correct answer as it describes the loss of memories for events that happened before the onset of amnesia.
Step-by-step explanation:
Understanding Types of Amnesia
The loss of memories for events that occurred prior to the onset of amnesia is defined as Retrograde Amnesia. This type of amnesia affects the ability to recall episodic memories that happened before a traumatic event. Conversely, Anterograde Amnesia involves the inability to form new memories after the traumatic event. This often results from damage to the hippocampus, impacting memory consolidation. Additionally, there are phenomena such as proactive and retroactive interference, which can affect memory recall of old and new information respectively.