1. Forgetting, Memory Construction, and Improving Memory Module 33

2. Forgetting
An inability to retrieve information due to poor encoding, storage, or retrieval.
Preview Question 10: Why do we forget? At what points in the memory system can our memory fail us?

3. H.M. H.M. became unable to form new conscious memories
This is called anterograde amnesia
He did have the ability to learn nonverbal tasks
Can be classically conditioned
They are able to form implicit memories
Retrograde amnesia: inability to recall past memories

4. Implicit Memory H.M. is unable to make new memories that are
declarative (explicit), but he can form new
memories that are procedural (implicit). C B A
HM learned the Tower of Hanoi (game) after his surgery. Each time he plays it, he is unable to remember the fact that he has already played the game.

5. We cannot remember what we do not encode.
Encoding Failure
We cannot remember what we do not encode.

6. Encoding Failures Age can effect ability to encode
Brain areas are less responsive in older adults
Attention failures—can’t encode what we aren’t attending to

7. Storage Decay
Poor durability of stored memories leads to their decay. Ebbinghaus showed this with his forgetting curve.

8. Retaining Spanish
Bahrick (1984) showed a similar pattern of forgetting and retaining over 50 years.
Andrew Holbrooke/ Corbis

9. Storage Decay The physical storage of memory is still a mystery
BUT…scientists think memories may be inaccessible because:
They were never encoded
They were discarded
They cannot be retrieved

10. Retrieval Failure
Although the information is retained in the memory store, it cannot be accessed.
Tip-of-the-tongue (TOT) is a retrieval failure phenomenon. Given a cue (What makes blood cells red?) the subject says the word begins with an H (hemoglobin).

11. PORN: Proactive. Old. Retroactive. New.
Types of Interference
Proactive interference: OLD learning disrupts recall of new information
Retroactive interference: NEW learning disrupts recall of old information
PORN: Proactive. Old. Retroactive. New.

12. Interference Learning some new information may disrupt
retrieval of other information.

13. Retroactive Interference
Sleep prevents retroactive interference. Therefore, it
leads to better recall.

14. Interference Interference isn’t always negative
Positive transfer: previously learned information facilitates learning of new information

15. Motivated Forgetting
Motivated Forgetting: People unknowingly revise their memories.
Repression: A defense mechanism that banishes anxiety-arousing thoughts, feelings, and memories from consciousness.
Culver Pictures
Sigmund Freud

16. Today’s View
Most memory researchers think repression rarely, if ever, occurs
We can forget unnecessary, neutral information
We have a really hard time forgetting emotionally charged events

17. Why do we forget?
Forgetting can occur at any memory stage. We filter, alter, or lose much information during these stages.

18. Memory Construction
While tapping our memories, we filter or fill in missing pieces of information to make our recall more coherent.
Misinformation Effect: Incorporating misleading information into one's memory of an event.
Preview Question 11: How accurate are our memories?

19. Misinformation and Imagination Effects
Elizabeth Loftus Experiments: Eyewitnesses reconstruct their memories when questioned about the event.
Depiction of the actual accident.

20. Misinformation
Group A: How fast were the cars going when they hit each other? Group B: How fast were the cars going when they smashed into each other?

21. Memory Construction
A week later they were asked: Was there any broken glass? Group B (smashed into) reported more broken glass than Group A (hit).

22. Eyewitness Testimony https://www.youtube.com/watch?v=nbARxiM0W_Q

23. Source Amnesia
Source Amnesia: Attributing an event to the wrong source that we experienced, heard, read, or imagined (misattribution).

24. Children’s Eyewitness Recall
Children’s eyewitness recall can be unreliable if leading questions are posed. However, if cognitive interviews are neutrally worded, the accuracy of their recall increases. In cases of sexual abuse, this usually suggests a lower percentage of abuse.

25. Memories of Abuse
Are memories of abuse repressed or constructed? Many psychotherapists believe that early childhood sexual abuse results in repressed memories. However, other psychologists question such beliefs and think that such memories may be constructed.

26. Constructed Memories
Loftus’ research shows that if false memories (lost at the mall or drowned in a lake) are implanted in individuals, they construct (fabricate) their memories.
Don Shrubshell

27. Loftus TED Talk

28. Consensus on Childhood Abuse
Leading psychological associations of the world agree
on the following concerning childhood sexual abuse:
Injustice happens.
Incest and other sexual abuse happen.
People may forget.
Recovered memories are commonplace.
Recovered memories under hypnosis or drugs are unreliable.
Memories of things happening before 3 years of age are unreliable.
Memories, whether real or false, are emotionally upsetting.

29. Improving Memory Study repeatedly to boost long-term recall.
Spend more time rehearsing or actively thinking about the material.
Space rehearsal is better than mass rehearsal
Make material personally meaningful.
Use mnemonic devices:
associate with peg words — something already stored
make up a story
chunk — acronyms
Preview Question 12: How might we apply memory principles to everyday situations, such as remembering a person’s name or even the material of this chapter?

30. Improving Memory
Activate retrieval cues— mentally recreate the situation and mood.
Recall events while they are fresh — before you encounter misinformation.
Minimize interference:
Test your own knowledge.
Rehearse and then determine what you do not yet know.
© LWA-Dann Tardiff/ Corbis