Download ppt - BCE Lab

Dec 10th, 2012
Memory
 Memory: Active system that receives, stores,
organizes, alters, and recovers (retrieves)
information
 Acquired
 Encoding
 Stored in the brain
 Storage
 Later retrieved
 Retrieval
 Eventually (possibly) forgotten
Figure 7.2
FIGURE 7.2 Remembering is thought to involve at least three steps. Incoming information is first
held for a second or two by sensory memory. Information selected by attention is then transferred
to temporary storage in short-term memory. If new information is not rapidly encoded, or
rehearsed, it is forgotten. If it is transferred to long-term memory, it becomes relatively permanent,
although retrieving it may be a problem. The preceding is a useful model of memory; it may not be
literally true of what happens in the brain
Three-Box Model of Memory
Sensory Memory
 Function - holds information
long enough to be processed
for basic physical
characteristics
 Capacity - large
Sensory
Input
Sensory
Memory
 can hold many items at once
 Duration - very brief retention
of images
 0.3 sec for visual info
 2 sec for auditory info
Sensory Memory
Sensory
Input
Sensory
Memory
 Divided into two subtypes:
 iconic memory - visual
information
 echoic memory - auditory
information
 Visual or iconic memory
was discovered by Sperling
in 1960
Sperling’s Experiment
 Presented matrix of letters for
1/20 seconds
 Whole-report procedure
 Participants are asked to report
all the items of a display
 Partial-report procedure
 Participants are cued to report
only some of the items in a
display
Sperling’s Iconic Memory Experiment
Sperling’s Iconic Memory Experiment
Sperling’s Iconic Memory Experiment
Sperling’s Iconic Memory Experiment
Sperling’s Experiment
 Sounded low, medium or
high tone immediately after
matrix disappeared
 Tone signaled 1 row to report
 Recall was almost perfect
 Memory for images fades
after 1/3 seconds or so,
making report of entire
display hard to do
High
Medium
Low
Results from Sperling’s experiment demonstrating the existence of a brief visual sensory
store. Participants were shown arrays consisting of three rows of four letters. After the
display was turned off, they were cued by a tone, either immediately or after a delay, to
recall a particular one of the three rows. The results show that the number of items
reported decreased as the delay in the cuing tone increased.
Sensory Memory
 Sensory memory forms
automatically, without
attention or interpretation
Sensory
Input
Sensory
Memory
 Attention is needed to
transfer information to
working memory
Short-Term Memory (STM)
 A proposed intermediate system in which
information has to reside on its journey
from sensory memory to long-term
memory
Atkinson and Shiffrin (1968) Model
Proposes that as information is rehearsed in a limited-capacity
STM, it is deposited in long-term memory
Memory span
 The number of elements one can
immediately repeat back
 Typical short-term memory span is about
seven items of information (i.e., words)


George Miller (1957)
Shepard and Teghtsoonian (1961)

Information cannot be kept in STM indefinitely
George Miller
“The magical number
seven, plus or minus two:
Some limits on our
capacity for processing
information” (1956)
Working Memory
Holds the Information Needed to Perform a task
Memory system that provides temporary storage
for information that is currently being used in
some conscious capacity (Baddeley, 1986)
 Function - conscious processing of information
 where information is actively worked on
 Capacity - limited (holds 7 +/- 2 items)
 Duration - brief storage (about 30 seconds)
 Code - often based on sound or speech even with visual
inputs
 Reading 1
Baddeley’s theory of working memory in which a
central executive coordinates a set of slave systems.
Working Memory
 The Central Executive
 An attentional control mechanism for working memory
 Coordinating between the various subsystems
 Temporary activation of long-term memory
 Shifting between tasks or retrieval strategies
 Relying on the frontal lobe, mainly in the left hemisphere
 Use of language clearly relies on the central executive
Working Memory
 The visuospatial sketchpad
 Integrating spatial, visual, and kinesthetic information
 Phonological loop
 Articulatory loop
‘Inner voice’ used during rehearsal of verbal
information
 Able to maintain about 1.5 to 2 sec worth of material
in the loop
 Phonological store
 An ‘inner ear’ that hears the inner voice and stores
the information in phonological form

Word length effect
 wit, sum, harm, bay, top
 University,opportunity,aluminum,constitutional,auditorium
Working Memory
Phonological similarity effect
 "G, C, B, T, V, P” vs. “F, L, K, S, Y, G.”
 Performance is usually _____ when the items sound similar than when
the items sound different.
 The phonological store retains speech-based memory for a brief period
of time and unless material is rehearsed, it usually decays within 2
seconds.
 The articulatory control process, which is responsible for translating
visual information into speech-based codes, as well as transfering it to
the phonological store.
Processing depth
 Elaboration leads to better recall than shallow
processing
Type of
Processing
Deep
00
Shallow -Acoustic
Shallow - Visual
10
10
20
30
50
60
70
80
20Percent
30 40
40
50
60
70
of words recalled80
Percent of words recalled
90
90 100
100
Working Memory measures
 Digit span(Wechsler, 1974)
 Forward digit span (Botwinick & Storandt, 1974)
 Backward digit span (Gathercole & Alloway, 2008)
 Letter-number sequencing (Wechsler, 1997)
 Nonword repetition(Obrien et al., 2006)
 Wisconsin Card Sorting Test (WCST) (Miyake et al., 2000)
 Tower of Hanoi (TOH)/London (Korkman, Kirk, & Kemp, 1998)
 Random number generation (RNG) (Baddeley, 1998)
 Operation span (Miyake et al., 2000)
 Dual task (Papagno et al., 1991)
 N-back (Smith & Jonides, 1999)
 Delayed-recognition (Jha & McCarthy, 2000)
An illustration of the delayed match-to-sample task
Working Memory
The Frontal Cortex and Primate Working Memory
• Delayed match-to-sample tasks with
monkeys (Goldman-Rakic, 1992)
• Monkeys with lesions in the frontal cortex cannot
perform this working memory task.
• Human infants cannot perform similar tasks
successfully until their frontal cortices have
somewhat matured (around 1 year)
Lateral views of the cerebral cortex of a human (top) and of a
monkey (bottom). Area 46 is the region shown in darker color.
Working Memory - Neuropsychology
• Auditory-Verbal maintenance deficit following Left Supramarginal / Inferior
Parietal lesions, eg KF (Warrington & Shallice, 1969)
• Visual-spatial maintenance deficit following Right Inferior Parietal lesion, eg
ELD (Hanley et al 1991)
• Frontal patients impaired on manipulating information in Working Memory on
tasks such as card sorting (Milner, 1963) and selection-without-repetition
(Petrides & Milner, 1982)
• Age-related Working Memory deficits following frontal-striatal decline (Gabrieli,
1996)
Modality-specific, passive stores in posterior parietal/temporal cortex
Common executive processes in frontal cortex
Neural Correlates of Working Memory
 The phonological loop – Speech
 Left hemisphere: frontal and parietal
regions
 The visuo-spatial sketchpad –
Nonspeech
 Right hemisphere
 The central executive – Domain
general
 Frontal lobe and ACC (anterior
cingulate cortex)
Anderson, Cognitive
Psychology and Its
Implications, Edition 7e –
Chapter 6
Awh et al., 1996
Anderson, Cognitive
Psychology and Its
Implications, Edition 7e –
Chapter 6
Modality independent
(Schumacher et al., 1996)
Anderson, Cognitive
Psychology and Its
Implications, Edition 7e –
Chapter 6
Baddeley, 2003
Memory aids
 Chunking
 Hierarchical organization
 Rehearsal
Chunking
 Grouping small bits of information into larger units of
information
 expands working memory load
 Which is easier to remember?
 4 8 3 7 9 2 5 1 6
 483 792 516
Hierarchical Organization
 Related items clustered together to form categories
 Related categories clustered to form higher-order categories
 Remember list items better if list presented in categories
 poorer recall if presented randomly
 Even if list items are random, people still organize info in some logical
pattern
Figure 7.4
FIGURE 7.4 A hypothetical network of facts about animals shows what is meant by the structure
of memory. Small networks of ideas such as this are probably organized into larger and larger units
and higher levels of meaning.
Training your working memory
Working Memory
Baddeley’s Theory of Working Memory (2003)
Memory Formation
 Retrograde Amnesia: Forgetting events that occurred
before an injury or trauma
 Anterograde Amnesia: Forgetting events that follow an
injury or trauma
 Consolidation: Forming a long-term memory
 Electroconvulsive Shock (ECS): Mild electrical shock
passed through the brain, causing a convulsion; one way to
prevent consolidation
Amnesia
 Retrograde
Amnesia
 Loss of past
memory
 Anterograde
Amnesia
 Can’t form new
memories
Anterograde Amnesia
Figure 7.5
FIGURE 7.5 The tower puzzle. In this puzzle, all the colored disks must be moved to another post,
without ever placing a larger disk on a smaller one. Only one disk may be moved at a time, and a
disk must always be moved from one post to another (it cannot be held aside). An amnesic patient
learned to solve the puzzle in 31 moves, the minimum possible. Even so, each time he began, he
protested that he did not remember ever solving the puzzle before and that he did not know how to
begin. Evidence like this suggests that skill memory is distinct from fact memory.
Long-Term Memory
Long-Term Memory
Explicit
Implicit

Available to conscious retrieval

Experience-induced change in
behaviour

Can be declared (propositional)

Cannot be declared (procedural)

Examples
 “What did I eat for breakfast?”
(episodic)
 “What is the capital of Spain?”
(semantic)
 “What did I just say?”
(working)

Examples
 Subliminal advertising?
(priming)
 How to ride a bicycle
(skills)
 Phobias
(conditioning)
Long-term Memory
Declarative
Non-declarative
Episodic
Semantic
Priming
Procedural
Conditioning
What did I
have for
breakfast?
What is the
capital of
France?
Facilitated
processing
How to ride
a bicycle
Reflex response to
new stimuli
Explicit Memory
 Also known as declarative or conscious memory
 Properties:
 memory consciously recalled or declared
 Can use to directly respond to a question
 Two subtypes of explicit memory
Episodic Memory
 Memory tied to your own personal experiences
 Examples:
 what did you have for dinner?
 do you like to eat caramel apples?
 Why are these explicit memories?
 Because you can actively declare your answers to these questions
Semantic Memory
 Memory not tied to personal events
 General facts and definitions about the world
 Examples:
 who was George Washington?
 what is a cloud?
 what is the climate at the north pole?
 These are explicit memories because you can describe what you know about
them.
 Unlike episodic memories, your knowledge does NOT include your
personal experience
 i.e., You may never have been to the north pole but do know about it.
Implicit Memory
 Also known as nondeclarative memory
 Influences your thoughts or behavior, but does not enter consciousness
 Three subtypes
Classical Conditioning
 Studied earlier
 Implicit because it is
automatically retrieved
Priming
 Priming is influence of
one memory on another
 Unscramble the
following words:
O R E S
 priming is implicit
because it does not
depend on awareness and
is automatic
 Here is a demonstration
L T E P A
K T A L S
 TSME
L O B S O M S
 ELAF
Procedural Memory
 Memory that enables you to perform specific learned skills or
habitual responses
 Examples:
 Riding a bike
 How to speak grammatically
 Tying your shoe laces
 Why are these procedural memories implicit?
 Can’t readily describe their contents

try describing how to tie your shoes
 They are automatically retrieved when appropriate
Procedural Memory
Serial Reaction Task
Rotary–Pursuit
Mirror Tracing
(e.g. Hazeltine et al., 1997)
(e.g. Gabrieli et al., 1997)
(e.g. Corkin, 1968)
Procedural - Neuropsychology
 Amnesic patients show intact:
 Rotary Pursuit (Corkin 1968)
 Serial Reaction Task (Nissen & Bullemer 1987)
 Alzheimer’s patients show intact:
 Rotary Pursuit (Gabrieli et al 1993)
 Mirror Tracing (Heindel et al 1989)
 Parkinson’s patients impaired on:
 Rotary Pursuit (Heindel et al 1989)
 Serial Reaction Task (Ferraro et al 1993)
 Huntington’s patients impaired on:
 Rotary Pursuit (Gabrieli et al 1997)
 Serial Reaction Task (Willingham & Koroshetz 1993)
but not:
 Mirror Tracing (Gabrieli et al 1997)
 Cerebellar lesions impair Mirror Tracing (Sanes et al 1990)
Procedural - Neuroimaging
 Rotary Pursuit learning correlates with activity in Primary and Secondary Motor
Cortex (Grafton et al 1992)
 Serial Reaction Task correlates with activity in Primary and Secondary Motor Cortex,
and Basal Ganglia (Hazeltine et al 1997)
 Two hypotheses:
1. Learning repetitive sequence involves Basal Ganglia-Thalamic-Motor Cortical loop
Learning new visual-motor mappings involves Cerebellar-Motor Cortical loop
2. Open-loop learning (minimal feedback): Basal Ganglia-Thalamic-Motor Cortical loop
Closed-loop learning (continual feedback): Cerebellar-Motor Cortical loop
 Rotary Pursuit and Serial Reaction Task involve open-loop motor learning with little
visual feedback (impaired by Basal Ganglia lesions)
 Mirror Tracing involves much visual feedback (impaired by Cerebellar lesions)
Need to examine nonvisual feedback
Episodic Memory - Neuroimaging
• MTL activations during episodic encoding (Tulving et al 1996) and retrieval
(Schacter et al. 1996)
Anterior-Posterior dissociation? (Lepage et al. 1998; Schacter et al. 1999)
• Left Frontal during Encoding (Shallice et al., 1994), right during Retrieval
“HERA: Hemispheric Encoding Retrieval Asymmetry” (Tulving et al., 1994)
• Posterior cingulate / Precuneus (Fletcher et al., 1996)
• Left lateral inferior parietal cortex (Henson et al., 1999)
Network of Frontal - Medial Temporal – Posterior areas all involved:
Frontal areas control encoding and retrieval of memories?
Posterior association areas store components of memories?
Medial Temporal regions (temporarily) bind different components?
• Finer spatial resolution (fMRI) beginning to dissociate MTL regions, eg
Hippocampus / Perirhinal for “Recollection / familiarity”? (Aggleton &
Brown, 1999)
Semantic Memory - Neuroimaging
• Common activation in Left Inferior Frontal,
Inferior Temporal, Angular gyrus and Temporal
pole for semantic judgments to words and
pictures (Vandenberghe et al 1996)
• Left Inferior Temporal activations for animal and
tool naming, Temporal Pole for people naming
(Damasio et al., 1996)
• Left Inferior Temporal activation for categoryversus letter-fluency (Mummery et al 1996)
• Left Middle Temporal and Premotor activations
for tool vs animal naming, Left Middle Occipital
for animal vs tool naming (Martin et al 1996)
Distributed representations, with activations
reflecting object’s interaction with world? E.g.,
tool naming activates motor regions
McClelland and Rogers, 2003
Basic Neuroanatomy of Memory
A) Subcortical structures
 Basal ganglia and cerebellum – Procedural
memory. Caudate nucleus involved particularly
with habit formation (unconscious learning)
 Thalamus – Temporal sequencing information.
Also supplementary role to medial temporal
lobes in new learning
 Basal forebrain – The binding together of
different modal components in episodic
memory
B. Cortical structures
 Hippocampus – Acquisition of new factual
knowledge
 Primary association cortex – Visual, auditory
and somatosensory data
 Non-medial temporal – Retrieval of previously
learned material e.g. autobiographical info,
names, faces
 Ventromedial frontal lobes – Memory traces
linking facts and emotion
 Dorsolateral frontal lobes – Recency and
frequency memory. Working memory
Memory
Declarative
Non-declarative
Episodic
Semantic
Priming
Procedural
Conditioning
What did I
have for
breakfast?
What is the
capital of
France?
Facilitated
processing
How to ride
a bicycle
Reflex response to
new stimuli
Medial temporal
Diencephalon
Mammillary
bodies
Frontal lobe
Lateral
Temporal /
Frontal lobes
Many cortical
regions…
Basal Ganglia
Cerebellum
Motor cortex
Cerebellum/
Amygdala
(MTL?)
Measuring Memory
 Tip-of-the Tongue (TOT): Feeling that a memory is
available but not quite retrievable
 Feeling of Knowing: Feeling that allows people to predict
beforehand if they will be able to remember something
(typically seen on game shows like Jeopardy)
 Recall: Supply or reproduce facts or information with some
external cues; direct retrieval of facts or information
 Hardest to recall items in the middle of a list; known as
Serial Position Effect
 Easiest to remember last items in a list because they are
still in STM
Figure 7.7
FIGURE 7.7 The serial position effect. The graph shows the percentage of subjects correctly
recalling each item in a 15-item list. Recall is best for the first and last items.
Measuring Memory (cont'd)
 Recognition Memory: Identifies correctly previously
learned material
 Usually superior to recall
 Distractors: False items included with a correct item
 Wrong choices on multiple-choice tests
 False Positive: False sense of recognition
Figure 7.8
FIGURE 7.8 (a) “Treasure map” similar to the one used by Kosslyn, Ball, and Reiser (1978) to study
images in memory. (b) This graph shows how long it took subjects to move a visualized spot
various distances on their mental images of the map.
Eidetic Imagery (Somewhat Like
Photographic Memory)
 Occurs when a person (usually a child) has visual images
clear enough to be scanned or retained for at least 30
seconds
 Usually projected onto a “plain” surface, like a blank piece
of paper
 Usually disappears during adolescence and is rare by
adulthood
Figure 7.9
FIGURE 7.9 Test picture like that used to identify children with eidetic imagery. To test your eidetic
imagery, look at the picture for 30 seconds. Then look at a blank surface and try to “project” the
picture on it. If you have good eidetic imagery, you will be able to see the picture in detail. Return
now to the text and try to answer the questions there. (Redrawn from an illustration in Lewis
Carroll’s Alice’s Adventures in Wonderland.)
Relearning
 Learning again something that was previously learned
 Used to measure memory of prior learning
 Savings Score: Amount of time saved when relearning
information
Forgetting
 Nonsense Syllables: Meaningless three-letter words (fej,





quf) that test learning and forgetting
Curve of Forgetting: Graph that shows the amount of
memorized information remembered after varying lengths
of time
Encoding Failure: When a memory was never formed in
the first place
Memory Traces: Physical changes in nerve cells or brain
activity that occur when memories are stored
Memory Decay: When memory traces become weaker;
fading or weakening of memories
Disuse: Theory that memory traces weaken when
memories are not used or retrieved often
Figure 7.10
FIGURE 7.10 The curve of forgetting. This graph shows the amount remembered (measured by
relearning) after varying lengths of time. Notice how rapidly forgetting occurs. The material learned
was nonsense syllables. Forgetting curves for meaningful information also show early losses
followed by a long gradual decline, but overall, forgetting occurs much more slowly.
Memory in the courtroom
Additional Theories of Forgetting
 Memory Cues: Any stimulus associated with a memory;
usually enhance retrieval of a memory
 A person will forget if cues are missing at retrieval time
 State-Dependent Learning: When memory retrieval is
influenced by body state; if your body state is the same at
the time of learning AND the time of retrieval, retrievals
will be improved
 If Robert is drunk and forgets where his car is parked, it
will be easier to recall the location if he gets drunk
again!
Figure 7.12
FIGURE 7.12 The effect of mood on memory. Subjects best remembered a list of words when their
mood during testing was the same as their mood was when they learned the list.
Even More (!) Theories of Forgetting
 Interference: Tendency for new memories to impair
retrieval of older memories, and vice versa
 Retroactive Interference: Tendency for new memories to
interfere with retrieval of old memories
 Proactive Interference: Prior learning inhibits (interferes)
with recall of later learning
Figure 7.13
FIGURE 7.13 The amount of forgetting after a period of sleep or of being awake. Notice that sleep
causes less memory loss than activity that occurs while one is awake.
Figure 7.14
FIGURE 7.14 Effects of interference on memory. A graph of the approximate relationship between
percentage recalled and number of different word lists memorized. (Adapted from Underwood,
1957.)
Figure 7.15
FIGURE 7.15 Retroactive and proactive interference. The order of learning and testing shows
whether interference is retroactive (backward) or proactive (forward).
More on Forgetting
 Repression: Unconsciously pushing painful, embarrassing
or threatening memories out of awareness/consciousness
 Motivated forgetting, according to some theories
 Suppression: Consciously putting something painful or
threatening out of mind or trying to keep it from entering
awareness
Flashbulb Memories
 Memories created during times of personal tragedy,
accident, or other emotionally significant events that are
especially vivid
 Where were you when you heard that the USA was
attacked on September 11th, 2001?
 Includes both positive and negative events
 Not always accurate
 Great confidence is placed in them even though they may
be inaccurate
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
Déjà vu (似曾相识）
Déjà vu
Scientific explanations
 Dual processing (2 cognitive processes momentarily
out of synchrony)
 Neurological (seizure, disruption in neuronal
transmission)
 Memory (Implicit familiarity of unrecognized stimuli)
and attentional (unattended perception followed by
attended perception)