How are sentences stored in LTS?
Explicit tasks; episodic memory
Sachs (1967)
STUDY subjects hear a story
“…A wealthy manufacturer,
Matthew Boulton, sought out
the young inventor…”
TEST
yes-no recognition
(1) identical sentence
(2) change form, but not
meaning (formal)
(3) active/passive change
(4) semantic change
correct response
yes
no
ONLY (4) CHANGES MEANING
no
no
Sachs Results
Form
Change
50%
Active/
Passive
False
Alarms
Semantic
Change
10%
|
immediate
|
80 syllables
later
|
160 syllables
later
Test is
You forget the form of the sentence, but
remember the meaning
In STS, you remember the actual words of the
sentence.
In LTS, you remember the meaning, but forget
the wording.
False Alarm Method
Try to get subjects to make a false alarm on a
yes-no recognition test
It shows what part of the episode they
remembered and what part they forgot
e.g., in Sachs (1967), false alarms to items with
same meaning, but different wording
Sentences in LTS are stored as propositions
Ratcliff & McKoon (1978)
Study list of sentences
.
.
.
“The geese crossed the
horizon as the wind shuffled
the clouds.”
.
.
.
1. CROSS (GEESE, HORIZON)
2. SHUFFLE (WIND, CLOUDS)
3. AS (1,2)
Predict
horizon “closer” to
geese than to wind
Item recognition priming test
“clouds”
“yes”
“chair”
“no”
.
.
.
“geese” OR “wind” “yes” PRIME
“horizon”
“yes” TARGET
RT to horizon
when geese is prime
600 msec
when wind is prime
630 msec
Why?
Either because GEESE is closer to HORIZON
in sentence
(surface structure)
Or because GEESE and HORIZON are in the
same proposition
(propositional hypothesis)
STUDY
“The kitten that the girl was
carrying scratched the lawyer”
SCRATCH (KITTEN1, LAWYER1)
CARRY (GIRL1, KITTEN1)
TEST (item recognition priming)
PRIME
“kitten”
“girl”
TARGET
“lawyer”
“lawyer”
Integration Hypothesis
Propositions that contain the same concepts
connect together in memory
Example:
“A car hit a tree. The tree fell on a wire,
and the wire touched another car.”
HIT (CAR1, TREE1)
FALL-ON (TREE1, WIRE1)
TOUCH (WIRE1, CAR2)
Concepts already in semantic memory
Car
Tree
Wire
Integration Hypothesis
Propositions that contain the same concepts
connect together in memory
Example:
“A car hit a tree. The tree fell on a wire,
and the wire touched another car.”
 HIT (CAR1, TREE1)
FALL-ON (TREE1, WIRE1)
TOUCH (WIRE1, CAR2)
Concepts already in semantic memory
Tree
Car
is
Car1
is
hit
Tree1
Wire
Integration Hypothesis
Propositions that contain the same concepts
connect together in memory
Example:
“A car hit a tree. The tree fell on a wire,
and the wire touched another car.”
HIT (CAR1, TREE1)
 FALL-ON (TREE1, WIRE1)
TOUCH (WIRE1, CAR2)
Concepts already in semantic memory
Tree
Car
is
Car1
is
hit
Tree1
Wire
is
fall on
Wire1
Integration Hypothesis
Propositions that contain the same concepts
connect together in memory
Example:
“A car hit a tree. The tree fell on a wire,
and the wire touched another car.”
 HIT (CAR1, TREE1)
 FALL-ON (TREE1, WIRE1)
 TOUCH (WIRE1, CAR2)
Concepts already in semantic memory
Tree
Car
is
Car1
is
hit
Tree1
is
Car2
Wire
is
fall on
Wire1
Based on Bransford & Franks (1971)
tree
in
shaded
man
front
yard
tall
smoked
pipe
Actually presented
“The tree shaded the man who was
smoking a pipe”
Never presented (but consistent)
“The tree in the front yard shaded
the man”
Never presented (inconsistent)
“The tree broke the window”
Support for integration hypothesis
Bransford & Franks (1971)
McKoon & Ratcliff (1980)
“The lawyer gestured to a waiter.”
The waiter brought coffee.
The coffee stained the napkins.
The lawyer flourished documents.
The documents explained a contract.
The contract satisfied a client.
Propositions
GESTURE TO (LAWYER1, WAITER1)
.
.
.
etc.
is
is
is
Waiter
1
Coffee
1
Napkins
1
Document
1
is
Contract
1
is
Client
1
is
Lawyer
1
is
Waiter
is
Coffee
Napkins
is
is
is
Waiter
1
Coffee
1
Napkins
1
Document
1
is
Contract
1
is
Client
1
is
Lawyer
1
Lawyer
Document
Contract
Client
Nodes for Concepts
already in semantic memory
is
is
is
Waiter
1
Coffee
1
Napkins
1
Document
1
is
Contract
1
is
Client
1
is
Lawyer
1
is
Document to Waiter = 2 links
Document to Napkins = 4 links
Prediction
“waiter” primes document more than “napkins” does
Recognition Test
client
pen
lawyer
sofa
waiter OR napkins
documents
PRIME
TARGET
RT to say “yes” to documents
665 msec with waiter as prime
704 msec with napkins as prime
Supports integration hypothesis
“Sally likes pets. She has a black cat.”
LIKES (SALLY, PETS)
HAS (SALLY, CAT1)
IS (CAT1, BLACK)
humans
keep
pets
cats
chase
mice
dogs
like
bones
“Sally likes pets. She has a black cat.”
LIKES (SALLY, PETS)
HAS (SALLY, CAT1)
IS (CAT1, BLACK)
humans
keep
pets
is
Sally
cats
chase
mice
dogs
like
bones
“Sally likes pets. She has a black cat.”
LIKES (SALLY, PETS)
HAS (SALLY, CAT1)
IS (CAT1, BLACK)
humans
keep
pets
is
Sally
cats
chase
cat1
mice
dogs
like
bones
“Sally likes pets. She has a black cat.”
LIKES (SALLY, PETS)
HAS (SALLY, CAT1)
IS (CAT1, BLACK)
humans
keep
pets
is
Sally
cats
chase
cat1
mice
black
dogs
like
bones
Directly stated propositions and inferences
“Sally likes pets. She has a black cat.”
Directly-stated
SALLY HAS A CAT
Inferences
Propositions that follow from the
directly-stated propositions
or from other inferences
SALLY LIKES CATS
(1) Logical inferences
necessarily follow from directlystated propositions
e.g.,
Sally has a pet
Sally’s cat is a mammal
(2) Pragmatic inferences
are probably true, but not
necessarily true
e.g.,
Sally takes good care of
her cat
Sally buys cat food
Inferences in Real Life
Commercials
“Four out of five doctors recommend
the ingredients in Anacin”
Court Room
Harris, Teske & Ginns (1975)
Witness:
“I went up to the
burglar alarm”
Memory test
“Did the witness say that they rang the
burglar alarm?”
Nearly everyone said “yes” even when instructed
not to draw inferences
Turtles Experiment
Bransford, Barclay & Franks (1972)
Group 1
STUDY
“Three turtles rested beside a floating log
and a fish swam beneath them.”
TEST
“Three turtles rested beside a floating log
and a fish swam beneath it.”
Result: very few false alarms
Group 2
STUDY
“Three turtles rested on a floating log
and a fish swam beneath them.”
TEST
“Three turtles rested on a floating log
and a fish swam beneath it.”
Result: many false alarms!
Group 2 propositions
rest on
floating
log
swim
beneath
3
turtles
fish
Inference added to memory:
causes false alarms to test
sentence with fish swimming
beneath log
Conclusion:
Memory contains inferences as well as
directly stated propositions
Schemas
An organized set of propositions that describes
the general characteristics of some thing or
activity. (Stored in semantic memory)
Restaurant Schema
roles: CUSTOMER
(human)
SERVER
(human)
1. ENTER (CUSTOMER, RESTAURANT)
2. SIT-AT (CUSTOMER, TABLE)
3. GREET (SERVER, CUSTOMER)
4.
.
.
.
BRING (BILL, TO CUSTOMER, BY SERVER)
PAY (CUSTOMER, BILL)
LEAVE (CUSTOMER, RESTAURANT)
Other examples:
Quiz show, coins
Restaurant Schema
Human
is
Restaurant
is
in
Customer
at
Table
Menu
Waiter
takes
Order
Schemas and Inferences
Schema Instantiation Inferences propositions that link concepts in a text to
concepts in a schema
TEXT: “John went to the White Horse”
“He sat down . . “
John
is
Restaurant Schema
go to
customer
White
Horse
go
to
restaurant
is
Schema instantiation inferences
IS (JOHN, CUSTOMER)
IS (WHITE-HORSE, RESTAURANT)
How memory and comprehension fail when you
do not make schema instantiation inferences.
Bransford and Johnson (1972)
“Clothes washing” experiment
No title
given
Title given
before reading
Recall
(number of
“ideas”)
2.8
5.3
Rated
comprehension
(1-7 pt. scale)
2.3
4.5
If you don’t know it’s about clothes washing,
you can’t connect the text to your clothes
washing schema.
Bridging Inferences
Inferences that fill gaps in the text by using
information from a schema.
“John went to the White Horse.
He ate and left.”
Inference
JOHN PAID HIS BILL
is
John
ate
go to
White
Horse
Restaurant Schema
left
is
customer
something
pays
bill
go to
restaurant
McKoon & Keenan (1974)
Investigation of Memory
for Bridging Inferences
Read
“A camper carelessly threw a match.
A great forest was destroyed.”
Camper
1
Forest
1
Great
threw
was
Match
1
Destroyed
McKoon & Keenan (1974)
Investigation of Memory
for Bridging Inferences
Read
“A camper carelessly threw a match.
A great forest was destroyed.”
Camper
1
Bridging
Inference
made by
consulting
“forest fire”
schema
Great
threw
start
Match
1
Fire
1
burn
Forest
1
was
Destroyed
True-false Test
Directly-stated
A great forest was destroyed.
T
or
F ?
Inferences
The match started a fire.
T
or
F ?
Conclude:
Inference
stored
in LTS
RT
to say
“true”
immediate
test
20 minutes
later
‘Nancy’ Experiment
Owens, Bower & Black (1979)
p.355 in text
Nancy woke up feeling sick again and
wondered if she was pregnant. How would she
tell the professor she was seeing?…
Nancy arrived at the cocktail party. She
looked around the room to see who was there.
She went to talk with her professor. She felt she
had to talk to him but was nervous. … Nancy
went over to the refreshments. The hors
d’oeuvres were good but she wasn’t interested in
talking to the rest of the people. ….
Nancy Experiment
Recall Results
Directly-stated
Propositions
Inferences
(Nancy got sick
at the party)
with
theme
29.2
without
theme
20.2
15.2
3.7
•Schema improves memory for directly-stated
proposition
•It also promotes recall of inferences which were
never mentioned
Childhood Amnesia
Recall
birth
now
serial position for your whole life
Repression? (Freud’s theory)
Language acquisition?
Difference between infant and adult schemas?
Waldvogel (1948)
number of memories


14 Recall your
childhood
memories
12 -

10 86-


4-
females
2

|
0


|
1


|
2

males

|
3
|
4
|
5
|
6
|
7
Sheingold & Tenney (1979)
Asked questions about birth of younger
sibling.
Answers confirmed by parents.

accuracy
score



|
1-2
|
3-4

|
5-6
Age
|
7-8
No memories before 3
|
9+
Do animals show “childhood” amnesia
frogs
yes
guinea pigs
no
Rats
yes
May depend on how “advanced”
animal is at birth
Stoloff & Spear (1976)
15-day old rats (still infants)
36-day old rats (young, but not babies)
shock
Trained
until
perfect
in T-maze
Tested 1 day later and 21 days later
36-day olds
100%
correct
turn
chance
training
1-day
later
21-days
later
Older rats forget what they knew as babies
Conclude
Little evidence for repression explanation
Language may play a role (but only in humans!)
Schema Explanation
Schemas for early memories are
different than those for adults
can’t consciously access them
Early
sensory-motor
schemas
Later
proposition
schemas
The effects of schemas on judgment
Hindsight Bias
The outcome of an uncertain situation is judged
to be more likely if you already know what
happened.
Rochester Nuke Plant Case
Hindsight bias in assigning blame in
accident
steam
tube
tools
reactor
core
Experimental Demonstrations of
Hindsight Bias
Fischoff (1975)
•subjects read about war between British and
Gurkas
•then they judge the likelihood of the war
outcome
Estimated Probability
British
Gurkas
Nobody
win
win
win
Told nothing
(no hindsight)
.40
.20
.40
Told “British
actually won”
.55
.12
.33
Told “Gurkas
actually won”
.32
.35
.33
Arkes et al. (1981)
Doctors given a case history to read
Is it disease A or disease B?
Group 1 - told nothing about real diagnosis
Group 2 - told “correct” diagnosis was disease A
Group 3 - told “correct” diagnosis was disease B
Result: probability estimates were higher for
“correct” diagnosis
So:
Hindsight Bias
•Hindsight bias happens when you warn people
to avoid it
•It does not happen when subjects don’t believe
the outcome information
Explaining Hindsight Biases by Schemas
•Outcome info activates schema
•Schemas guide retrieval of facts
•Retrieved facts bias judgments of probability
Medical example: heart attack or indigestion
Symptoms
smokes
felt pain after dinner
skipped heart beats
burps a lot
Explaining Hindsight Biases by Schemas
•Outcome info activates schema
•Schemas guide retrieval of facts
•Retrieved facts bias judgments of probability
Medical example: heart attack or indigestion
Symptoms
smokes
felt pain after dinner
skipped heart beats
burps a lot
heart
attack
schema
indigestion
schema
Mnemonic Devices
External Aids -- notes, string . . .
Internal Aids
used at
encoding
used at
retrieval
Internal Aids used at Encoding
Basic Strategy
 make
each item distinctive
(reduce interference)
 make a collection of items meaningfully related
(instantiate a schema)
 use a retrieval strategy to make sure you don’t
miss anything
Method of loci
 used
for serial recall
 makes items distinctive and allows for a good
retrieval strategy
Peg words
serial recall
 distinctive
 good retrieval strategy

one - bun
two - shoe
three - tree
four - door
five - hive
six - sticks
seven - heaven
eight - gate
nine - wine
ten - zen
Keyword method
for foreign language vocabulary
Paling (Dutch) = Eel (English
make image of
Emphasizes distinctiveness and useful retrieval
strategy
Chunking Strategies
(for lists)
BROWN
EEL
sentence
story
image
NAIL
PAPER
Emphasize distinctiveness and meaningfulness
of collection
People with Good Memories
Exceptional ability or just good strategies?
How specific are the abilities
S. (studied by Luria)
 had
very vivid mental imagery

serial recall of 70-word lists
retained for years

used method of loci
An exceptional memory with no imagery
V.P. (studied by Hunt & Love)
Continuous Paired Associate Task
JUK - 23
ROQ - 29
CUH - 13
JUK - ?
CUH - 97
ROQ - ?
CUH - ?
VP
100%






|
2
|
4

College
Students

Recall


|
|
6
8
Lag

|
10

|
12
etc.
VP’s digit span = 25
Story recall - nearly perfect
after 1 year
•Used rapidly generated semantic associations
No mnemonic devices at all
Elizabeth (Stromeyer
Eidetic Memory
“Photographic”
10,000 dots
Results are questionable
No mnemonic devices at all
Elizabeth (Stromeyer
Eidetic Memory
“Photographic”
10,000 dots
Results are questionable
No mnemonic devices at all
Elizabeth (Stromeyer
Eidetic Memory
“Photographic”
10,000 dots
Results are questionable
Conclusions
•People don’t just have good or bad memory
as a whole -- they have good or bad memoryrelated skills.
(e.g., good imagery, good ability to form
semantic associations)
•For verbal memory, mnemonic devices are
needed for exceptional performance, but these
don’t need to involve imagery.
 THE CAR CLIMBED THE HILL.
 THE CAR CLIMBED THE HILL.