Long-term Memory Classification

Beyond the declarative/procedural and episodic/semantic distinctions, research has identified several further phenomena that reveal just how complex and varied long-term memory really is.

Flashbulb memories are unusually detailed memories formed of events that were highly arousing or surprising at the time. They function almost like a photograph taken with an advanced camera: once 'captured', the same detailed scene can seemingly be looked back at again and again, essentially unchanged. One explanation for why flashbulb memories are so vivid is that people may put in extra mental effort while forming them — engaging in deeper processing and generating more retrieval cues than they would for an ordinary event.

Autobiographical memory refers to a person's own personal memories, and these are not distributed evenly across a lifetime. Some periods of life produce noticeably more memories than others. Almost no memories are typically reported from very early childhood, particularly the first four to five years of life — a phenomenon called childhood amnesia. There is then a sharp increase in the frequency of memories from just after early adulthood, roughly the twenties, while a decline in certain kinds of memory tends to begin around thirty years of age. In old age, the most recent years of life are usually the best remembered of all. Emotionality, novelty, and the personal importance of events are all thought to contribute to how much autobiographical memory a given period of life leaves behind. …