Transcript Module 33
Forgetting, Memory
Construction, and Improving
Memory
Module 33
Forgetting
An inability to retrieve information due to
poor encoding, storage, or retrieval.
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
Implicit Memory
H.M. is unable to make new memories that are
declarative (explicit), but he can form new
memories that are procedural (implicit).
A
B
C
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.
Encoding Failure
We cannot remember what we do not
encode.
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
Storage Decay
Poor durability of stored memories leads to
their decay. Ebbinghaus showed this with
his forgetting curve.
Retaining Spanish
Bahrick (1984) showed a similar pattern of
forgetting and retaining over 50 years.
Andrew Holbrooke/ Corbis
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
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).
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.
Interference
Learning some new information may disrupt
retrieval of other information.
Retroactive Interference
Sleep prevents retroactive interference. Therefore, it
leads to better recall.
Interference
Interference isn’t always negative
Positive transfer: previously learned information
facilitates learning of new information
Motivated Forgetting
Motivated Forgetting:
People unknowingly
revise their memories.
Culver Pictures
Repression: A defense
mechanism that banishes
anxiety-arousing
thoughts, feelings, and
memories from
consciousness.
Sigmund Freud
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
Why do we forget?
Forgetting can occur at
any memory stage. We
filter, alter, or lose
much information
during these stages.
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.
Misinformation and Imagination Effects
Elizabeth Loftus Experiments: Eyewitnesses reconstruct
their memories when questioned about the event.
Depiction of the actual accident.
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?
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).
Broken Glass? (%)
50
40
32
30
20
14
10
0
Group A (hit)
Group B (Smashed into)
Verb
Eyewitness Testimony
https://www.youtube.com/watch?v=nbARxiM0W_
Q
https://www.youtube.com/watch?v=I4V6aoYuDcg
Source Amnesia
Source Amnesia: Attributing an event to the
wrong source that we experienced, heard, read,
or imagined (misattribution).
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.
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.
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
Loftus TED Talk
https://www.youtube.com/watch?v=PB2OegI6wvI
Consensus on Childhood Abuse
Leading psychological associations of the world agree
on the following concerning childhood sexual abuse:
1.
2.
3.
4.
5.
6.
7.
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.
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:
1.
2.
3.
4.
5.
associate with peg words — something already
stored
make up a story
chunk — acronyms
Improving Memory
5.
6.
7.
Activate retrieval cues— mentally recreate
the situation and mood.
Recall events while they are fresh — before
you encounter misinformation.
Minimize interference:
1.
2.
Test your own knowledge.
Rehearse and then determine what you do not
yet know.
© LWA-Dann Tardiff/ Corbis