Memory
Memory
Memory
Memory
Memory
Memory
Memory
Memory
Memory
Memory
Memory
Memory
Memory
True or False??
1. When people go around a circle saying their names,
their poorest memories are for what was said by the
person just before them.
2. Our experiences are etched on our brain, just as the
grooves on a tape receive and retain recorded
messages.
3. Although our capacity for storing information is
large, we are still limited in the number of
permanent memories we can store.
4. The hour before sleep is a good time to commit
information to memory.
Recall vs Recognition
Grouchy
Gabby
Fearful
Sleepy
Smiley
Jumpy
Hopeful
Shy
Droopy
Dopey
Sniffy
Wishful
Puffy
Dumpy
Sneezy
Lazy
Pop
Grumpy
Bashful
Cheerful
Teach
Shorty
Nifty
Happy
Doc
Wheezy
P-Diddy
The Answers
• Research suggests the order, from
most likely to least likely recalled
is as follows:
–
–
–
–
–
–
–
Sleepy
Dopey
Grumpy
Sneezy
Happy
Doc
Bashful
Seven Dwarfs and STM
• Now, turn over the sheet and recall
the names of the seven dwarfs on
the back of the sheet
Memory
•Memory
– persistence of learning over time
via the storage and retrieval of
information
Memory
•Encoding
– the processing of information into the
memory system
•Storage
– the retention of encoded information
over time
•Retrieval
– process of getting information out of
memory
Ebbinghaus and Memory
•Systematic and
controlled study of
memory in
laboratory
H. Ebbinghaus (1850-1909)
Ebbinghaus and Memory
• Ebbinghaus
– Used nonsense syllables: TUV
ZOF GEK MONUL WAV
FALEM
– the more times practiced on
Day 1, the fewer repetitions to
relearn on Day 2
Ebbinghaus’ Retention Curve
Time in
minutes
taken to
relearn
list on
day 2
20
15
10
5
0
8
16
24
32
42
53
Number of repetitions of list on day 1
64
Ebbinghaus and Forgetting Curve
• Most forgetting
occurs right
after learning
– approx. 50% in
first 40 min
• Relationship
between delay
and forgetting
not linear
Ebbinghaus and Memory
•Other important findings
– Beneficial effects of distributed
practice for repetitions (ie.,
‘spacing effect’)
– List-length effect
Encoding
•Automatic Processing
•Effortful Processing
Encoding
Effortful
Automatic
Types of Encoding
•Encoding Meaning
•Acoustic Encoding
•Visual Encoding
Encoding Aids
•Meaning (semantics)
•Imagery
•Mnemonics
– memory aids
– E.g., ‘peg-word’ system
Encoding Aids
•Mnemonics
– Method of loci
Encoding Aids
•Chunking
–organizing items into
familiar, manageable units
–use of acronyms
•HOMES-Huron, Ontario,
Michigan, Erie, Superior
Remember as many of the
following numbers as you can:
•1776198514922004
•1776198514922004
Remember as many of the
following letters as you can:
•XIBMSATMTVPHDX
•X IBM SAT MTV PHD X
Encoding Aids
•Hierarchies
– Organization of knowledge
under narrower
concepts/headings
•Rehearsal
– conscious repetition of
information
Memory Storages
•Sensory
•Short term (working memory)
•Long term
The Modal Memory System
Stage 1: Sensory Memory
• Iconic memory was demonstrated in
Sperling’s classic experiment, and
lasts about 1/3 second
• Echoic memory
• Iconic and echoic memory systems
may allow us to experience the world
as a continuous stream
Stage 1: Sensory Memory
Stage 2: Short-Term Memory
•Short-Term Memory
– limited in duration and capacity
– George Miller’s “magical” number
7 +/- 2
Stage 2: Short-Term Memory
Percentage
who recalled
consonants
90
80
70
60
50
40
30
20
10
0
Rapid decay
with no
rehearsal
3
6
9
12
15
18
Time in seconds between presentation
of contestants and recall request
(no rehearsal allowed)
Stage 3: Long-Term Memory
• Rajan Mahadevan’s Amazing
Memory
– Memorized first
30,000 numbers of PI
• Solomon
Shereshevskii
– “What a crumbly yellow voice you have.”
– Would “feel” images, “taste” colors, and “smell”
sounds
Stage 3: Long Term Memory
Long Term Memory Systems
• Explicit memory involves
conscious effort
• Implicit memory occurs
without deliberate effort
Explicit Memory
• Explicit memory involves the
processes used to remember specific
information which can be declared
• Episodic memory is personal
• Semantic memory involves
knowledge of facts
Implicit Memory
• Implicit memory is the pervasive process
by which people show without awareness
that they are remembering something
• Implicit memory does not require
attention and is automatic
• Consider “procedural memory”
• Repetition priming
Retrieval
•Recall
– retrieve information learned earlier
•Recognition
– identify items previously learned
Retrieval Cues
•Reminders of information we
could not otherwise recall
•Guides to where to look for info
– Context Effects
•Priming
– the activation, often unconsciously, of
particular associations in memory
Retrieval: Priming
Retrieval: State Dependence
Percentage of
words recalled
40
30
20
10
0
Water/
land
Land/
water
Different contexts for
hearing and recall
Water/
water
Land/
land
Same contexts for
hearing and recall
Retrieval
•Mood-Congruent Memory
– tendency to recall experiences
that are consistent with one’s
current mood
Forgetting
•Interference
– Proactive (forward-acting)
Interference
– Retroactive (backwards-acting)
Interference
Interference and Forgetting
Interference and Forgetting
Percentage
of syllables
recalled
90%
Without interfering
events, recall is
better
80
After sleep
70
60
50
40
30
20
10
After remaining awake
0
1
2
3
4
5
6
7
Hours elapsed after learning syllables
8
Amnesia
• Retrograde
Amnesia
– Loss of past
memory
• Anterograde
Amnesia
– Can’t form new
memories
Anterograde Amnesia
Demonstration
•Take out paper and pen…
How many of you
remembered…
•Flame
•Smoke
•Fire???
•Bed
•Snore
•Sleep???
Flashbulb Memories: Where
were you when…
•Brown & Kulik
– JFK assassination
•Neisser & Harsch
– Challenger explosion study
Are traumatic memories
accurate?
•Generally accepted theory:
– Central facts remembered more
accurately
– Peripheral details inaccurate and
often fabricated in later stories
Eyewitness Testimony
Method:
Show video of car
accident
2 conditions: “hit” vs.
“smash”
Results:
Broken glass? No, but
one week later:
“smashed” = 33% yes
“hit” = 14% yes
False Memories
•Loftus
– Imagination inflation
– Mall study
•Leo
– Suspects found to make false
confessions during police
interrogations
Attention and Memory
•Attention: internal processes
used to focus our awareness on
a subset of perceptual
information
•Attention affects what we
remember
Cocktail Party Phenomenon
Cocktail Party Phenomenon
•Studied in labs using the
dichotic listening technique
– Two different messages presented, one in
each ear
– Participants later asked to recall
information, or sometimes have to
“shadow” the words presented to one ear
“Much of intelligent behavior
depends on successfully
managing your attention. For
example, while driving a car,
you might devote most of your
attention to the conversation,
but if the traffic gets bad or if
you have to look for a particular
street, you might shift you
attention more to the driving…”
CHAIR
LEOPARD
SNOW
TISSUE
COFFEE
GRASS
CHURCH
CHAIR
LEOPARD
Selective Attention:
Recognition Test
Circle the words that you think were on the list that was presented
to your unattended ear.
tiger
tree
snow
igloo
leopard
coffee
church
wine
carrot
grass
chair
mail
book
temple
novel
tissue
Biology of Memory
•Karl Lashley (1950)
– trained rats to solve maze, then
cut out pieces of their cortex and
retested their memory of maze
– partial memory retained
Biology of Memory
• Lashley found beer to have same
effects as cortex removal on rat
maze performance
Biology of Memory
•Hippocampus
– Involved in explicit memory
•Cerebellum
– Involved with implicit memory
– Skills, conditioning, procedural
memory
Improve Your Memory
• Study repeatedly to boost recall
• Spend more time rehearsing or
actively thinking about the material
• Make material personally meaningful
• Use mnemonic devices
– associate with peg words--something already stored
– chunk information into acronyms
• Study in spaced intervals
Improve Your Memory
• Activate retrieval cues--mentally
recreate situation and mood
• Minimize interference
• Test your own knowledge
– to rehearse it
– to determine what you do not yet know