Lecture 21 - Schemas and Scripts Flashcards
Schemas
scripts?
knowledge about the world
− Scripts are a specific type of schema: sequence of events in schema
structure in memory
pre-loaded experiences telling you how to encode current info: shapes interpretation of what’s happening now and how you recall that info later
So far, out study of memory (STM/WM and LTM) has focused
on lists or words or simple sentences. Is this what memory is
typically used for?
• Outside the laboratory, our memory encodes current information
to help us understand situations and act within them.
• Memories of similar/relevant instances in the past reduce the
cognitive complexity of the present situation.
• Memory is a constructive process, using current input + topdown
(previously encoded) knowledge.
Outside the laboratory, our memory encodes…
…current information
to help us understand situations and act within them.
Memories of similar/relevant instances in the past reduce the…
…cognitive complexity of the present situation.
it simplifies the present moment because some of the things that have been experienced before don’t need to be encoded
Memory is a constructive process,
using current input mixed with topdown (previously encoded) knowledge.
all memories being dynamically mixed with what you’re experiencing now
A study by Anderson et al (1977) used the same text,
interpreting the same information in different ways
took different populations of students instead of priming them with images like we did in class
• 64% of physical education majors interpreted the passage as having to do with wrestling.
• Only 28% of music majors thought it was associated with
wrestling.
• Default: Most interpreted it as a prisoner planning escape.
suggests: you bring a certain background anytime you’re interpreting new information - but if someone is primed with an image that interpretation can be altered
recall
is a reconstructive process
In a similar study by Bransford and Johnson (1972) using
passages of complex text describing a scene, recall for
events in the story doubled (32% vs 16%) when a
descriptive title ("the doctor" or the dentist") was provided.just enough to activate top-down info to shape how you recall
able to frame things, encode them within this schema
Clearly some semantic priming is occurring, but how does
it work for a complex event?
A schema is….
…..a general knowledge structure used for
understanding or interpreting complex situations (information).
- any real world setting
something you do repeatedly you will build a schema for that event (dinner, lecture, travel, ect…)
qualities of schemas
• A schema is general for a type of situation, and helps give organizational structure to an specific event.
- helps you structure individual episodes
• Schemas are more than a bunch of facts – they are structured to include the relationships between facts.
• Most importantly, schemas provide relevant top-down knowledge.
- what you bring to bear in any new situation
• For example, you might have schemas for what to expect and what to do at the movies, a basketball game, lecture, family
dinner, etc.
A schema is general for a type of situation, and helps give
organizational structure to an specific event.
Based on an accumulation of events, you build up schemas
for different situations. This builds….
…. expectations for specific elements during some episode.
because you know what to expect you don’t have to do as much detection
e.g. The last time you went out to a restaurant:
Typical ‘dining’ schema elements: • What kind of food do they serve? • What did you eat? • Was it good? • Was it expensive? • Was the service good?
Less typical ‘dining’ schema elements:
- Did the server write down your order?
- Were any children present?
- Were there any clowns?
any schema will be general for a specific situation and will have typical and nontypical elements
slots
values
default assumption
Each schema has slots that are placeholders for expected (typical) items. Each slot can be filled with (appropriate) values from the current situation. If no value for a slot is
provided, the schema may have a default assumption.
Restaurant dining slots
EX
- Food types served:
- Food purchased:
- Food quality:
- Cost:
- Service quality:
more declarative stuff
Your individual defaults
EX
Italian Chicken parmesan Fair Cheap Just okay
Current values
EX
Italian Ravioli Good Cheap ? - fill in default value of "just okay"
default value
When some information is
incomplete or isn’t encoded, you
can assume the default value.
are both what you expect to happen and what is pre-built into the schema
episodes over time build up your defaults
you fill in default values when you don’t remember
they tend to be more individual related
Schemas are more than a bunch of facts –
they are structured
to include the relationships between facts.
Most importantly, schemas provide
relevant top-down
knowledge.
example schemas
you might have schemas for what to expect and
what to do at the movies, a basketball game, lecture, family dinner, etc.
The default values in schemas can lead to characteristic mistakes.
Brewer and Treyens (1981) examined schemas for places.
- doctor office, dentist office, library, etc… (you expect certain things there)
- Participants waited in a graduate student office for 35 seconds.
- They were then taken out and asked to recall the items in the office.
Subjects had good recall for items that fit a graduate office schema
(i.e. desk, chair). However, 30% of
subjects reported seeing books, even though none were present.
==> Books are a default expectation, so they are recalled even though
they were not present in that instance.
People in the same cultures…
…tend to share the same slots in schemas, but your individual defaults may vary based on personal experience and preferences.
the schema is your…
framework for interpreting things and you have certain expectations and defaults
People in the same cultures tend to share the same slots in
schemas, but your individual defaults may vary based on
personal experience and preferences.
ex?
- People in the U.S. tend to tip after a meal, but the default amount may vary.
- People in different cultures may not tip at all.
• You can also embed schemas. For example, the going-to-dinner
schema could be part of a going-on-a-date schema.
A script is a…
… specific type of schema. They are much more
structured and have a specific order of events.
* lots of scripts often embedded in a schema. * There are causal links between events in the script. Changing an event (outcome) changes the script.
script or schema?
what happens if you change the outcome of the slot?
Food purchased: (?)
Script slots • Order is placed: True • Food arrives: True • Order is correct: False • Pay for food: False
Do people actually use scripts? Bower and colleagues (1972)
did a number of experiments regarding how people produce and
use scripts.
Experiment 1
• Participants were asked to free-associate and write a list of actions
that they think people do in various situations (e.g. go to a lecture, get up in the morning, go to a restaurant, etc.).
• They found great uniformity for “basic actions” described in scripts (e.g. out of 730 total actions (total slots to be filled by schemas) for ‘restaurant’ only four were completely unique and were given by a single person).
• This suggests that people encode and later recall similar elements
from a similar type of event.
Bower and colleagues (1972) also asked (different)
participants to recall facts about stories.
• People were presented with passages that contained six ordered events/actions. They each had a title (e.g. “The
Doctor).
− Stories could be in typical order (typical script) or scrambled.
- They were later (after a 20 minute delay) provided with just the title and asked to recall each line from the story.
- Stories presented in the correct order were recalled with 50%
accuracy. Stories in scrambled order can 18% accuracy.
- causal relationship made recall easier: logical: easier to encode, easier to recall
- Recall was better when the items followed the typical script, suggesting an organization role in understanding and memory.
- Additionally, people added 1 fact (on average) that was plausible given the context.
Schemas and scripts seem most compatible with which
model of memory?
PDP model: encoding context at the same time that we’re encoding declarative facts
- we make up a story that fits the high points
The descriptions of schemas and scripts seem very vague
and hard to characterize.
Although schemas seem to be made of _____, much of the activity appears more ____ and harder to state (confabulate).
declarative facts
procedural
The rules and dependencies seem like post hoc confabulation
have this memory system to encode or recall or a system to make up stories (rules for confabulation)
because we’re doing stuff in a scene and then we have to state later
How are the dependencies established, particularly when
slots can be filled with new items?
PDP may be a way of addressing this, as experience
forms the dependency
use episodic info to build semantic info
but no two situations are exactly the same - details always in flux
Schemas and scripts should break down when
some defaults are violated.
The descriptions of schemas and scripts seem very vague
and hard to characterize.
- describe things in terms what you’ve seen before: what’s your memory? stuff that happens a lot: circular: just remembering those things that have happened before
because things are responding largely to the context
Just as we use schemas to understand (encode) events, we also use them later during recall.
• Source monitoring is the process of determining the origin of
some memory or belief.
• Sometimes we use stereotypes (a schema for a person) to
reconstruct a memory.
• This can be very useful – as with all schemas you don’t need to
recall every detail, but can fill-in with defaults.
• However, this can (and does) lead to many errors.
Source monitoring
is the process of determining the origin of
some memory or belief.
trying to decide: where did that memory come from?
what is the original source for the thing currently in working memory?
Sometimes we use stereotypes (a schema for a person) to
reconstruct a memory.
reduces computational complexity: know what to expect
don’t have to pay as much attention: you know what to expect
fill in with default values
if you build up episodes and build up schemas to deal with situations and people
it takes a lot of new episodes to change
Marsh, Cook, & Hicks (2006) examined the
role of gender stereotypes on source (what produced the memory) attributions.
• Subjects read statements (e.g. “I like
baseball.”), that were attributed to one of two
people: Chris or Pat.
• Sentences were masculine, feminine, or
neutral.
• Subjects were given a puzzle (delay) and later
told the gender of the people (Chris is a
heterosexual male, Pat is a heterosexual
female).
• They then re-read the statements, and asked
the source (who had said them).
• People were more accurate when the
statements matched the stereotypes
(schemas).
