Distinguish the types of forgetting: anterograde amnesia, retrograde amnesia, encoding failure, retrieval failure, and interference (both retroactive and proactive). I already know the answer to this, here you go peeps: Anterograde amnesia is a decreased ability to retain new information. Retrograde amnesia is when you lose existing, already made memories. Encoding failure is when information does not get stored properly in the memory. This could alter memories or not store them entirely. Retrieval failure is when previously made memories can't be accessed. Retroactive interference is when new learning interferes with old learning, whereas proactive interference is when old learning interferes with new learning.