Memory impairment Long term memory impairment 2021-03-07T22:48:25Z Long term memory loss A deficit in the ability to retrieve information from long-term memory, which can be defined as a seemingly unlimited capacity to store memories can last years and relate to the performance of actions or skills (i.e., procedural memories, knowing how) and memories of facts, rules, concepts, and events (i.e., declarative memories, knowing that).