Why we forget The 7 causes of memory failure

The importance of forgetting  At this point in the unit, you know the three types, processes, and stages of memory. Now, let’s move on to an equally important topic: forgetting.  “Forgetting is as important as remembering. If we remembered everything, we should be as ill off as if we remembered nothing. It would take as long for us to recall a space of time as it took the original time to elapse, and we should never get ahead with our thinking.” –William James

The dynamics of forgetting  Forgetting can occur at any memory stage  As we process information, we filter, alter, or lose much of it

Reason #1: Encoding failure  Information never enters long-term memory; not paying attention to details produces encoding failure (bigger problem as you get older) External events Sensory memory Short- term memory Long- term memory Attention Encoding failure leads to forgetting

Remember the penny activity?  Which penny is the real thing? Do you know now? Probably not.

Reason #2: Storage decay  Physical fading away of a memory trace over time when it is not used: “use it or lose it” Time in days since learning list Percentage of list retained when relearning

Reason #3: Retrieval failure  Forgetting can result from failure to retrieve information from long-term memory External events Attention Encoding Retrieval failure leads to forgetting Retrieval Sensory memory Short-term memory Long-term memory

Reason #4: Interference  Learning some items may disrupt retrieval of other information  Proactive interference:  Retroactive interference:

The two directions of interference

Limiting retroactive interference: a tip  The hour before bed is a good time to memorize new material! Without interfering events, recall is better After sleep After remaining awake Hours elapsed after learning syllables 90% Percentage of syllables recalled

Reason #5: Motivations for Forgetting  Motivated Forgetting  Repression

Reason #6: Memory Construction  Memories are not files retrieved from a hard drive; they are actively and imperfectly constructed every time you retrieve them from a vast network of associations  We filter information and fill in missing pieces, often leading to distortions;  Retrieval of memories is subject to bias and suggestibility; imagination inflation  Misinformation Effect  Source Amnesia

Reason #7: Memory Disorders  Age-associated memory impairment:  Prospagnosia:  Post-concussion syndrome:  Alzheimer’s Disease: degenerative condition of the brain; affects 4 million Americans today  Other strange stories related to #6 and #7 to come…