1. Memory: Persistence of learning over time through the storage and retrieval of information
Memory depends on encoding, storing, and retrieving information
STEPS: External events  sensory memory  short term/working memory  long term memory
WM: Automatic or effortful encoding
Can be aided by the timing of rehearsals, imagery, and mnemonic devices
WM has short duration and limited capacity
LTM: is limitless and constructive
Works by leaving traces of neural impulses
Long term potentiation  permanent change in synapses
Stress hormones influence memory
We have implicit (cerebellum) and explicit (hippocampus)LTM
Retrieval of information happens by recall, recognition or faster relearning
Priming (unconscious), context effects, and mood congruence help us retrieve relevant information

2. Answers to previous questions?
When we learn new things, do we forget some of the old things “to make room”?
No matter what we learn about “timing of rehearsals,” why do we learn much better just before an exam?
Why do we remember details of events surrounding a traumatic experience so clearly?
Why do we sometimes have the eerie sense that we have “lived this moment before” ?

3. Module 22 – Forgetting, Memory Construction and Improving memory
What if we remembered everything?

4. Today’s interesting questions
Do you think that you may have repressed some of your memories and that they may be resulting in some unexplained fears or anxieties?
If you attended a French, German, or Italian language high school  Do you feel that your previous language skills are poorer now? How is that possible if memory is limitless?
Do you remember stuff better if you work at night or in the morning?
Should you memorize formulas or definitions the day before an exam or during the week before an exam?
Did anyone ever lie about what they heard from you, or what they saw you do?

5. 7 sins of the memory 3 sins of forgetting 3 sins of distortion
Absent mindedness – failure to encode
Transience – decay of storage
Blocking – failure to retrieve
3 sins of distortion
Misattribution – source of information
Suggestibility – effects of misinformation
Bias – current information influencing recall
1 sin of intrusion
Persistence of unwanted memories

6. Forgetting as encoding failure
Some information is encoded without effort
Some information requires effortful encoding or it never enters long-term memory
External
events
Sensory
memory
Short-
term
Long-
Attention
Encoding
failure leads
to forgetting

7. Forgetting as storage decay1 2 3 4 5 10 15 20 25 30 40 50 60
Time in days since learning list
Percentage of list retained when relearning
Ebbinghaus forgetting curve:
How much information is retained long term?
Memory for novel information fades quickly over the first 3 days, then levels out.

8. Time in years after completion of Spanish course
What if the information survives the first 3 days?
Similar forgetting curve for Spanish vocabulary learned by students
Retention
drops,
then levels off
½ 14½ ½ ½
Time in years after completion of Spanish course
100% 90 80 70 60 50 40 30 20 10
Percentage of
original
vocabulary
retained

9. Forgetting as 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
Long-term

10. Retrieval failure: Interference
Learning some items may disrupt retrieval of other information
Proactive (forward acting) Interference
disruptive effect of prior learning on recall of new information
E.g., remembering the new phone number
Retroactive (backwards acting) Interference
disruptive effect of new learning on recall of old information
E.g., learning new students’ names interfere with the recall of the names of previous students.

12. Effects of sleep on information retrieval
Retroactive Interference is minimal during sleep
Without interfering
events, recall is
better
After sleep
After remaining awake
Hours elapsed after learning syllables
90% 80 70 60 50 40 30 20 10
Percentage
of syllables
recalled

13. Retrieval failure: Motivated forgetting
people unknowingly revise memories in self-serving ways.
Repression
We banish from consciousness anxiety-arousing thoughts, feelings, and experiences
Widely held belief  legacy of Freud
Memory researchers show that repression very rarely occurs

14. Forgetting Forgetting can occur at any memory stage
As we process information, we filter, alter, or lose much of it

15. Memory Construction We filter information and fill in missing pieces
Misinformation Effect: incorporating misleading information into one's memory of an event
Imagination Effect: incorporating imagined events into one’s “memory”.
Source Amnesia: attributing to the wrong source an event that we experienced, heard about, read about, or imagined (misattribution)

16. Misinformation Effect: Loftus experiment
Eyewitnesses reconstruct memories when questioned
Depiction of actual accident
We imagine information as we tell. After repeated retellings, imagined information is incorporated in the memory.
Leading question:
“About how fast were the cars
going when they smashed into / hit each other?”
Memory
construction

17. Source Amnesia
The frailest aspect of memory is the source of information
Imagination  recollection
Source amnesia of preschoolers: an experiment
Children did activities with “Mr. Science”
Mothers read stories about Mr. Science.
They recalled events that were only in the stories.

18. MEMORY IS RECONSTRUCTION
Children as eyewitnesses
Experiment by Ceci and Bruck:
A list of some likely and some very unlikely events
Children asked to think “very carefully” and report
After 10 weekly interviews, 58% of preschoolers produced vivid false memories of unlikely events
“Repressed” memories of abuse
Clinicians point of view differ from that of memory researchers
The difference in opinion has important legal and ideological ramifications
It is common to forget experiences that are difficult to interpret
We recover memories (good or bad) when cued
We cannot reliably report about things that happened before the age of 3 – infantile amnesia
Memories (real or false) can be stressful