2.2 Forgetting

Why we forget

Encoding failure happens when information never enters long-term memory in the first place — you never really paid attention. Decay theory says memories fade over time if not used, weakening the memory trace. Retrieval failure occurs when the memory exists but you can't access it, as in the tip-of-the-tongue phenomenon.

Interference: memories competing

Proactive interference is when old information disrupts recall of new information (an old phone number blocks a new one). Retroactive interference is the reverse — new learning disrupts recall of older information. Both show that memories can interfere with each other rather than simply disappearing.

Motivated forgetting & cues

Repression, a Freudian concept, is the idea that people unconsciously push disturbing or threatening memories out of awareness to protect themselves. Retrieval also depends on cues: without the right context or state, memories may seem forgotten even though they're stored, illustrating encoding specificity — cues present at encoding aid later retrieval.

Key terms

Encoding failure

Information never enters long-term memory due to lack of attention or processing.

Decay theory

The idea that memory traces fade over time if not accessed or used.

Proactive interference

Old information disrupts the recall of newly learned information.

Retroactive interference

New information disrupts the recall of previously learned information.

Repression

A Freudian concept describing the unconscious blocking of disturbing or threatening memories from awareness.

Try an AP-style question

What is this?

1. Motivated forgetting
2. Source amnesia
3. Proactive interference
4. Retroactive interference