MEMORY
Memory: Models and Research Methods
By Wajiha Ghazal
FEEDBACK ACTIVITY
• How do illusions help us understand
perception?
• What are iconic storage and echoic
storage, and how do they help us
understand the “real” world?
• What is “automatic processing?” Give
some examples of automatic
processing from your everyday life
experiences?
• What have cerebral imaging
techniques told us about attention?
MEMORY IS …
• Memory is the means by which we retain
and draw on our past experiences to use
that information in the present.
• The mechanism we use:
• to create, maintain and
• retrieve information about the past
experiences
Cognitive Psychologists have identified three common
operations of memory: Encoding, Storage, and Retrieval
PROCESSES IN
MEMORY
Encoding
Sensory data is transform into a form of mental
representation.
Storage
Encoded information is kept into memory.
Retrieval
Information stored is pull out or use from the memory
Tasks Used for
Measuring Memory
RECALL VERSUS
RECOGNITION TASKS
• Recall, you produce a fact, a word, or other item from
memory. Fill-in-the-blank and most essay tests require
that you recall items from memory.
• Recognition, you select or otherwise identify an item as
being one that you have been exposed to previously.
Multiple-choice and true-false tests involve some
degree of recognition.
TYPES OF RECALL TASKS
• Three main types of recall tasks are used in experiments.
 Serial recall (you recall items in the exact order in which
they were presented.)
 Free recall (you recall items in any order you choose)
 Cued recall (you are first shown items in pairs, but during
recall you are cued with only one member of each pair
and are asked to recall each mate. Cued recall is also
called “paired-associates recall” )
 Relearning, which is the number of trials it takes to learn
once again items that were learned in the past.
RECOGNITION TASKS
•
Recognition memory is usually much better than recall.
•
A study by Standing and colleagues (1970) demonstrated
that participants could recognize close to 2,000 pictures in a
recognition-memory task.
•
Some psychologists refer to recognition-memory tasks as
tapping receptive knowledge. Receptive means
“responsive to a stimulus”.
 Recognition-memory task, you respond to stimuli presented
to you and decide whether you have seen them before or
not.
 Recall-memory tasks, you have to produce an answer,
require expressive knowledge.
IMPLICIT VERSUS EXPLICIT
MEMORY TASKS
•
•
Explicit memory tasks
– Involves conscious recollection
– Participant knows they are trying to retrieve information
from their memory
Implicit memory tasks
• unconscious recollection of information
• priming tasks and tasks involving procedural knowledge
– Require participants to complete a task
– The completion of the task indirectly indicates memory
MEMORY TASKS
• imp_ _ _ _ _.
– Priming is the facilitation
of your ability to utilize
missing information
– Priming even works in
situations where you are
not aware that you have
seen the word before
PROCEDURAL MEMORY OR MEMORY
FOR PROCESSES
– Procedural memory include the procedures involved in riding a
bike or driving a car.
– Many of the activities that we do every day fall under the
purview (influence) of procedural memory; these can range
from brushing your teeth to writing.
– Procedural memory is sometimes examined with the rotary
pursuit task.
•
The rotary pursuit task requires participants to maintain contact
between an L-shaped stylus and a small rotating disk
•
This disk is placed on a quickly rotating platform.
•
After learning with a specific disk and speed of rotation,
participants are asked to complete the task again,
•
either with the same disk and the same speed or with a new
disk or speed.
•
when a new disk or speed is used, participants do relatively
poorly as compare to same disk and speed, even if they do not
remember previously completing the task
•
Motor learning and hand-eye coordination
Mirror-tracing task
MIRROR-TRACING TASK
• A plate with the outline of a shape drawn on it is put behind a barrier
– Watch mirror image to trace a figure
– With practice, however, participants become quite efficient and accurate with this
task. Participants’ retention of this skill gives us a way to study procedural
memory.
– Mirror-tracing task is also used to study the impact of sleep on procedural
memory.
– Patients suffering from schizophrenia often have memory deficits as well as sleep
problems.
– Göder and colleagues (2008) found that when those patients received a
medication that increased the duration of their slow-wave sleep, their procedural
memory performance increased as well.
– learning a new motor skill
• Cognitive psychologists have developed models that
assume that both implicit and explicit memory influence
almost all responses. One of the first and most widely
recognized models in this area is the process-dissociation
model.
• Implicit memory is sometimes referred to as unconscious
memory or automatic memory. Implicit memory uses past
experiences to remember things without thinking about
them.
• Explicit memory requires conscious thought it is also known as
declarative memory
PROCESS-DISSOCIATION MODEL
(JACOBY, 1991)
• This model assumes that implicit and explicit memory both
have a role in virtually every response.
• Thus, only one task is needed to measure both these processes
• In an implicit memory test, subjects might try to complete a
word fragment with the first word that comes to mind
Conscious memory could contaminate the test if a subject
thinks back to a studied list for cues to the completion.
• In an explicit test, subjects might be instructed to intentionally
think back to the studied list to complete the word fragment. In
this case, unconscious memory could contaminate the test, if a
person cannot remember the item but guesses based on the first
item that comes to mind
•
Jacoby’s first innovation was to separate intentional
and unintentional influences by placing them in
opposition.
•
One study asked subjects to study a list of non-famous
names, and either a few minutes or a full day later, to
discriminate between famous and non-famous names
•
Subjects were told that none of the names on the
studied list were famous
•
if they consciously remembered studying a name they
could reject it as non-famous.
•
But studying the names made them more familiar, an
automatic influence that could easily be misattributed
to the name being famous.
•
Thus, subjects were more likely to call non-famous
names famous when they had been previously studied,
but only after a day’s delay when recollection for the
list was poor.
•
Placing conscious memory and automatic influences
of memory in opposition allowed them to be clearly
separated
•
Demonstrate that two processes are mediated
by separate brain systems
•
Kaufman has also argued that implicit memory, like
explicit memory, is an important part of human
intelligence
MODELS OF
MEMORY
• Represent ways that memory has been
conceptualized
– Atkinson & Shiffrin’s 3 Stage Model of
Memory
– Craik & Lockhart’s Level of Processing Model
– Baddeley’s Working Memory Model
– Tulving’s Multiple Memory Systems Model
– McClelland & Rumelhart’s Connectionist
Model
TRADITIONAL MODEL OF
MEMORY
• Atkinson & Shiffrin (1968) 3 Stage
Model
Stimuli
Sensory
Store
Short -Term
Store
Information Processing Model
Long -Term
Store
•
a sensory store, capable of storing relatively limited
amounts of information for very brief periods;
•
a short-term store, capable of storing information for
somewhat longer periods but of relatively limited capacity
as well; and
•
a long-term store, of very large capacity, capable of
storing information for very long periods, perhaps even
indefinitely
SENSORY STORE
•
The sensory store is the initial repository of much
information that eventually enters the short- and longterm stores. Strong evidence argues in favor of the
existence of an iconic store.
•
The iconic store is a discrete visual sensory register that
holds information for very short periods. Its name derives
from the fact that information is stored in the form of
icons.
•
These in turn are visual images that represent something.
Icons usually resemble whatever is being represented.
•
SENSORY MEMORY: SPERLING
•
DISCOVERY (1960) ICONIC
MEMORY RESEARCH
Whole report procedure
– Flash a matrix of letters for 50 milliseconds
– Identify as many letters as possible
– Participants typically remembered 4 letters
• Partial Report Procedure
– Flash a matrix of letters for 50 milliseconds
– Participants are told to report bottom row
– Participants were able to report any row
requested
B 5 Q T
2 H S 9
O 4 M Y
Averbach & Coriell (1961)
Iconic Memory Research
N M L C WD PQ
A X I N YK J U
- Showed matrix for 50 msec
- Place a small mark above a letter at different delays
- Results indicated that as many as 12 letters could be stored in
sensory memory
•
additional important characteristic of iconic memory: It
can be erased
•
Backward visual masking was also discovered with this
technique
•
If the mask stimulus is presented in the same location as
a letter and within 100 milliseconds of the presentation
of the letter, the mask is superimposed on the letter
•
For example, F followed by L would be E
•
Visual information appears to enter our memory system
through an iconic store.
•
This store holds visual information for very short periods.
•
In the normal course of events, this information may be
transferred to another store. Or it may be erased.
•
Erasure occurs if other information is superimposed
(overlap) on it before there is sufficient time for the
transfer of the information to another memory store.
SENSORY
STORES
• Iconic store or Visual sensory register
– Holds visual information for 250 msec longer
– Information held is pre-categorical/ HAVE
NO MEANING
– Capacity – up to 12 items
– Information fades quickly
• Echoic or Auditory sensory register
– Holds auditory information for 2-3 seconds
longer to enable processing
• Attention
SHORT-TERM
MEMORY
– Attend to information
in the sensory store, it
moves to STM
• Rehearsal
– Repeat the information
to keep it maintained in
STM
Rehearsal
Short Term
Memory
(STM)
• Retrieval
– Access memory in LTM Attention
and place in STM
• Information is stored
acoustically (by the way it
sounds) rather than
visually (by the way it
Storage &
Retrieval
Research on Short-Term Memory
• Miller (1956)
– Examined memory capacity
– our immediate (short-term) memory capacity for a
wide range of items appears to be about seven items,
Chunking - organize
the input into larger units
plus or minus two
– 1 9 8 0 1 9 9 8 2 0 0 3 - Exceeds capacity
– 1980 1998 2003 - Reorganize by chunking.
STORAGE CAPACITY
OF STM
• Vogel,
Woodman &
Luck (2001)
• Used colors
and
orientations
90
80
70
60
50
East
West
North
40
30
20
10
0
1st
Qtr
2nd
Qtr
3rd
Qtr
4th
Qtr
VOGEL, WOODMAN
& LUCK
RESULTS (2001)
• Can retain 3-4 colors or orientations
• Stores integrated objects, not just features
• American Sign Language, researchers
have found that short-term memory can
hold approximately four items for signed
letters
• This finding is consistent with earlier work on
visual-spatial short-term memory
LONG-TERM
MEMORY
• Some theorists have suggested that
the capacity of long-term memory is
infinite, at least in practical terms
• Duration
•
•
•
What is stored in the brain?
Wilder Penfield addressed
found that patients sometimes would
appear to recall memories from their
childhoods
– Potentially permanent
Long Term
Memory
(LTM)
BAHRICK’S RESEARCH ON
VERY LONG
TERM
• High school year books containing all of the names and
MEMORY
photos of the students were used to assess
memory
•
•
392 ex-high school students (17-74) took 4 different
memory tests:
– Free recall of the names
– A photo recognition test where they were asked to
identify former classmates
– A name recognition test
– A name and photo matching test
For some of the participants, it was as long as 48 years
since they graduated from High school
•
Permastore refers to the very long-term storage of
information, such as knowledge of a foreign language
of mathematics
•
Schmidt and colleagues (2000) studied the permastore
effect for names of streets near one’s childhood homes
•
author just returned to his childhood home of more
than 40 years ago
•
These findings indicate that permastore can occur
even for information that you have passively learned
•
Some researchers have suggested that permastore is a
separate memory system
•
Neisser (1999), have argued that one long term
memory system can account for both.
LEVELS OF PROCESSING MODEL OF
MEMORY
•
Craik & Lockhart (1972)
•
memory does not comprise three or even any specific
number of separate stores
•
varies along a continuous dimension in terms of depth
of encoding
•
there are theoretically an infinite number of levels of
processing (LOP) at which items can be encoded
through elaboration
•
There are no distinct boundaries between one level
and the next.
•
The emphasis on processing as the key to storage.
LEVELS OF PROCESSING MODEL
OF MEMORY
• Craik & Lockhart (1972)
– Different ways to process information lead to different
strengths of memories
– Deep processing leads to better memory
•
elaborating according to meaning leads to a strong memory
– Shallow processing emphasizes the physical features
of the stimulus
•
the memory trace is fragile and quickly decays
SUPPORT FOR LEVELS OF
PROCESSING
• Craik & Tulving (1975)
–
–
–
–
Participants studied a list in 3 different ways
Structural: Is the word in capital letters?
Phonemic: Does the word rhyme with dog?
Semantic: Does the word fit in this sentence?
The
is delicious.
•
•
•
•
•
•
SUPPORT FOR LEVELS OF
PROCESSING
The levels-of-processing framework can also be
applied to nonverbal stimuli.
Melinda Burgess and George Weaver (2003)
showed participants photos of faces
asked them questions about the persons of the
photo to induce either deep or shallow
processing.
Faces that were deeply processed were better
recognized
A level-of-processing benefit can be seen for a
variety of populations
People suffering from schizophrenia often suffer
from memory impairments because they do not
process words semantically
•
In the self-reference effect, participants show very high
levels of recall
•
when asked to relate words meaningfully to the
participants by determining whether the words
describe them
•
Objects can be better remembered, for example, if
they belong to the participant
•
each of us has a very elaborate self-schema
•
This self-schema is an organized system of internal cues
regarding our attributes, our personal experiences, and
ourselves
•
Thus, we can richly and elaborately encode
information related to ourselves
CRITICISMS OF LOP
MODEL
• Circular definition of levels
• some researchers noted some paradoxes in retention
• For example, under some circumstances, strategies that use
rhymes have produced better retention than those using just
semantic rehearsal
• The sequence of the levels of encoding may not be as
important
• Two other variables may be of more importance: the way
people
• process (elaborate) the encoding of an item (e.g.,
phonological or semantic), and the way the item is retrieved
later on
•Transfer appropriate processing effect
– Morris, Bransford, and Franks (1977)
– Two processing tasks: semantic vs. rhyme
– Two types of tests: standard yes/no recognition vs. rhyme
test
– Memory performance also depends on the match between
• encoding processes and type of test
BADDELEYS’ WORKING MEMORY
MODEL
•
Working memory holds only the most recently
activated, or conscious, portion of long-term memory
•
it moves these activated elements into and out of
brief, temporary memory storage
•
synthesizes the working-memory model with the LOP
framework
•
Baddeley originally suggested that working memory
comprises five elements
•
The visuospatial sketchpad, the phonological loop, the
central executive, subsidiary “slave systems,” and the
episodic buffer
BADDELEYS’ WORKING MEMORY
MODEL
WORKING MEMORY
MODEL
• Phonological Loop
•
•
•
Phonological storage
– Used to maintain information for a short time and for acoustic
rehearsal
– Subvocal rehearsal
– Tree, pencil, marshmallow, lamp, sunglasses, computer,
chocolate
– This phenomenon is called articulatory suppression
Visuo-spatial Sketch Pad
– Used for maintaining and processing visuo-spatial information
Episodic Buffer
• Bind information from the visuospatial sketchpad and the
phonological loop as well as from long-term memory into a
unitary episodic representation
WORKING MEMORY
MODEL
•
•
•
so that they make sense to us.
This incorporation allows us to solve problems and reevaluate previous experiences with more recent knowledge
Central Executive
– Focuses attention on relevant items and inhibiting
irrelevant ones
– Plans sequence of tasks to accomplish goals, schedules
processes in complex tasks, often switches attention
between different parts
– Updates and checks content to determine next step in
sequence of parts
– subsidiary slave systems
TULVING’S MULTIPLEMEMORY
• Explicit memory SYSTEMS MODEL
•
•
•
•
Semantic Memory
– General knowledge
– Facts, definitions, historical dates
Episodic Memory
– Event memories (first kiss, 6th birthday)
Implicit memory
Procedural Memory
– Memories on how to do something (skiing, biking, tying
your shoe)
– Habits and priming
MULTIPLE-MEMORY
SYSTEMS
MODEL
• Nyberg, Cabeza, & Tulving (1996)
SUPPORT
– PET technology to look at episodic and semantic
memory
– Asked people to engage in semantic or episodic
memory tasks while being monitored by PET
• Results
– Left (hemisphere) frontal lobe differentially active in
encoding (both) and in semantic memory retrieval
– Right (hemisphere) frontal lobe differentially active
in retrieval of episodic memory
CONNECTIONIST
PERSPECTIVE
• Parallel distributed processing model
– Memory uses a network
– Meaning comes from patterns of
activation across the entire network
– Spreading Activation Network Model
– Supported by priming effects
• Amnesias
DEFICIENT
MEMORY
– Retrograde Amnesia
• Loss of memory for events that occurred
before the trauma
– Infantile Amnesia
• Inability to recall events of young childhood
– Antereograde Amnesia
• No memory for events that occur after the
trauma
Amnesia, memory loss that occurs without other mental difficulties
CONT…
Retrograde amnesia,
memory is lost for
occurrences prior to a
certain event
• Usually, lost memories gradually reappear
• certain cases, some memories are lost
forever
• But even in cases of severe memory loss, the
loss is generally selective
Anterograde amnesia
loss of memory occurs
for events that follow an
injury.
• Information cannot be transferred from
short-term to long-term memory
• inability to remember anything other than
what was in long-term storage before the
accident
Amnesia is also a result
of Korsakoff’s syndrome,
a disease that afflicts
long-term alcoholic
• many of their intellectual abilities may
be intact,
• symptoms, include hallucinations and a
tendency to repeat the same story
over and over
ALZHEIMER’S
• Leads to memory loss andDISEASE
dementia in older
•
population
Atrophy of the cortical tissue
– Alzheimer brains shows abnormal fibers that appear
to be tangles of brain tissue and senile plaques
(patches of degenerative nerve endings)
– The resulting damage of these conditions may lead to
disruption of impulses in neurons
• Over the age of 65 are labeled ‘late onset’
• ‘Early onset’ is rare but can affect those in their
mid 30's and in middle age
ALZHEIMER’S
DISEASE
•
•
Symptoms (Gradual, Continuous & Irreversible)
–
–
–
–
–
–
–
–
–
Memory loss
Problems doing familiar tasks
Problems with language
Trouble knowing the time, date, or place
Poor or decreased judgment
Problems with abstract thinking
Misplacing things often, such as keys
Changes in mood and behavior
Changes in personality
These symptoms could be an early sign of Alzheimer's
when it affects daily life
HIPPOCAMPUS AND
MEMORY
• Hippocampus
– Critical for integration and consolidation
– Essential for declarative memory
– Without the hippocampus only the
learning of skills and habits, simple
conditioning, and the phenomenon of
priming can occur