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MEMORY
Can be studied from 2 perspectives:
1. Information-processing research
(software)
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uses computer concepts such as encoding,
storage, and retrieval
Biological research (hardware)
2.
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maps the physical structures and “wiring” of
the brain and nervous system
*Each has produced an independent line of
research.
INFORMATION PROCESSING APPROACH:
SOFTWARE OF MEMORY
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its goal is to discover what people do
with information from the time they
perceive it until they use it
particularly suited to describing changes
that take place over the lifespan
can distinguish between functions that
change a great deal and those that
change very little, either in one person or
in comparison with another
INFORMATION PROCESSING APPROACH:
SOFTWARE OF MEMORY (Cont’d)
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assumes that people
can handle only a
limited amount of
information at a given
time
assumes that
information that comes
in through the senses is
transformed by a series
of mental processes
into a form suitable for
storage and later recall
INFORMATION PROCESSING APPROACH:
SOFTWARE OF MEMORY (Cont’d)
*Most information-processing studies are
cross-sectional
 findings may reflect cohort differences
rather than age-related changes
Processes: Encoding, Storage and Retrieval
3 step filing system: encoding, storage,
retrieval
Before encoding:
 sensory input, attention, begin processing (do I
want to keep this? for how long?)
1. encoding: the process by which information is
prepared for long-term storage and later
retrieval
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2.
attaches a “code” or “label” to the information to
prepare it for storage; will be easier to find when
needed
storage: the process by, or location in which,
memories are retained for future use
3.
retrieval: the process by which information is
recalled from storage
*The precise mechanisms involved in encoding,
storage, and retrieval may vary with the situation,
the type of information and how the information is
to be used. Difficulties in any of these steps may
impair memory.
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the ability to retrieve newly encountered
information seems to drop off with age
younger adults can remember word pairs or
recognize pictures better than older people.
*More sophisticated strategies to encode
information for long-term storage are:
1. Organization: encoding strategy or
mnemonic device, consisting of
arranging or categorizing material to be
remembered
2. Elaboration: consisting of making
associations, often between new
information and information already in
memory
 the capacity of working memory to hold
and process information is widely
believed to shrink with age
Encoding Problems
 older adults seem to be less efficient than
younger ones at encoding new information to
make it easier to remember (e.g. less likely to
spontaneously arrange material in alphabetical
order to create mental associations)
 older adults can improve their encoding skills
through training or instruction (how much they
benefit depends on task)
 older people’s encoding seems to be less
precise, may reflect less education
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key factor = complexity of the task (effort)
Tasks that require reorganization,
elaboration, or mental manipulation show
the greatest falloff
Some researchers suggest that as
people get older they have less
attentional resources to focus on a task
Storage Problems:
 stored material may deteriorate to the
point where retrieval becomes difficult or
impossible
 a small increase in “storage failure” may
occur with age
Retrieval Problems:
 older adults may be able to answer a multiple
choice question but not an open-ended one
(recognition)
 have more trouble recalling items (pure recall
vs. cued recall)
 do as well in recognizing items they know
 takes longer to search their memories
 age differences are minimized when older
adults
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are familiar with the material
have an opportunity to practice, and
can work at their own pace
“Storehouses”: Sensory, Short-term
(STM), and Long-term (LTM)
 If you tried to assimilate all the sensory
inputs that flood your brain daily, you
would suffer from information overload
and be unable to focus.
 Sensory memory is fleeting to avoid this
problem
Processing begins in short-term memory:
STM:
 temporary storage (20-30 sec.) If content
not rehearsed and processed further, it
disappears.
Newer concept: WORKING MEMORY
(WM): Intermediate Short-Term Storage
 working memory: current thoughts and
processes. Whether from sensory
storage or from long-term storage.
 this information is consciously
manipulated or reorganized.
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working memory capacity varies across
individuals, related to intelligence.
better, more complex processing
more attentional resources
more items that can be brought out from
storage (retrieval)
juggling many balls at once
working memory contains whatever is in
consciousness at a given moment
WORKING MEMORY
current thoughts
new information
information retrieved from LTM
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can normally hold only about 5-9
separate chunks of information at a time
possible to increase the amount of
material held in working memory by
grouping items into larger chunks
items will remain in working memory only
about 30 seconds unless you engage in
rehearsal or some other purposeful effort
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other processes become automatic, so
as to free space in working memory: the
more automatization, the better working
memory works, e.g. multiplication tables
simple STM: no age differences
working memory: age differences
working memory for spatial tasks
declines more than for verbal tasks
some areas decline more than others
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memories not lost in STM are assumed
to be stored in LTM
so how come we can’t remember so
many things?
problems with retrieval: bringing contents
from LTM into working memory. It’s
there, but inaccessible.
Many reasons for retrieval failure:
 poorly encoded
 interference of other material
 conflicting emotions
 lack of practice
Types of retrieval:
 recognition
 recall
 cued recall
LONG TERM MEMORY (LTM)
 very large capacity (unlimited?) Everything that
has been stored at any time in one’s life.
 multiple systems with different brain parts
involved
 each system involved in a different type of
memory
 difficult to study in the laboratory: artificial
situation unlike real life, DVs not representative
of everyday life
 some research with real life variables: difficult
to pick the right ones, more difficult to
ascertain verosimilitude
LONG TERM MEMORY (LTM)
 impossible to function without it at any
age!
 important for sense of self (predicament
of amnesia sufferers).
 “Pure” memory: exercises in
remembering lists, words, numbers, etc.
(most of lab research)
 “Applied” memory: necessary for social
interaction, enjoyment of life and daily
functioning in any area
TYPES OF LONG TERM MEMORY (LTM)
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DECLARATIVE: (you say something you
remember)
NON-DECLARATIVE OR
PROCEDURAL: (you do something you
remember) Some of this bypasses
working memory.
EXPLICIT MEMORY: conscious – most
declarative
IMPLICIT: unintentional, unconscious –
most procedural
TYPES OF LONG TERM MEMORY (LTM)
DECLARATIVE: EPISODIC AND
SEMANTIC
 Episodic: events, activities, personal
experiences, discrete episodes affected
by age, similar events merge as one
 Semantic: general knowledge, can be
from accumulation of many episodic
events (language part of this), little
decline except for names
TYPES OF LONG TERM MEMORY (LTM)
PROCEDURAL: MOTOR, PERCEPTUAL
AND CONDITIONED
 Motor: riding bike, playing instrument,
automatic
 Perceptual: recall of features we were
not focusing on
 Conditioned: classical conditioning
Examples of Differing Contents of
Declarative and Nondeclarative
Memory
Declarative
Facts
Language
Social Customs
Personal episodes
Nondeclarative
Habits
Motor skills
Perceptual skills
Conditioned responses
Relationship Between Aging and
Performance in Various Types of
Memory
Sensory
No change or small decline
Working
Organization
Elaboration
Moderate to large decline
Moderate to large decline
Long-term
Declarative
Episodic
Memory for experience and activities
moderate to large decline
Personal history
moderate to large decline
Semantic
World knowledge increases with age
Vocabulary
increases with age
Nondeclarative
Skills
no change or small decline
Perceptual skills
no change or small decline
Motor learning
no change or small decline
Classical conditioning
no change or small decline
TYPES OF LONG TERM MEMORY (LTM)
PROSPECTIVE MEMORY:
 remembering to do something in the future
AUTOBIOGRAPHICAL MEMORY:
 events from one’s life, hard to check out.
Moderately traumatic events remembered
more than extremely traumatic events
(repression). Also important historical events
(very talked about at the time) or any event
with high emotional content.
 Flashbulb memories: very vivid, photo or
video-like. More from 10-20 years of age than
from later, for both young and old adults.
 Very long term memories sometimes called
remote or tertiary.
Age differences in episodic:
Recall: older adults worse off:
 omit more information
 include more extraneous material
 repeat previously recalled items
Cued recall: some improvement
Recognition: better, but still slightly worse
than young
Some variables that affect episodic memory
tests:
 attentional factors
 encoding strategies (e.g. imagery,
mnemonic aids such as method of loci)
 level of arousal
 time and speed, pacing
 cautiousness
 meaningfulness of material
 motivation (intrinsic and extrinsic)
Some variables that affect episodic memory
tests (Cont’d):
 incentives
 health status
 previous experience with test
 how organized is the material
 expectations
 SES
 interference: proactive (old material
affects new) and retroactive (new affects
old), the first is stronger in older adults
Some variables that affect episodic memory
tests (Cont’d):
 expertise
 self-efficacy (confidence in self)
 anxiety, stress and depression
 exercise
 nutrition (B vitamins)
 alcohol and other drugs
 medical drugs (interactions)
 smoking
Priming: an increase in ability to do a previously
encountered task or to remember previously
encountered material
 Both declarative and nondeclarative memory
can show effects of priming
 An unconscious, automatic process
 Speed is one indication that priming has
occurred
 To be effective, earlier and later stimuli should
be as close to identical as possible
 Seems to be equally efficient in younger and
older adults
 Normal older people whose episodic memory
has weakened can benefit as much from
priming as younger ones
Long-term Memory: Inactive Storage
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Not all contents within the long-term
memory are equally accessible
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Long-term memory is divided into
“rooms” with different kinds of contents,
and aging affects them differently
Overall, age is NOT a good predictor of
memory and learning capacity.
 Importance of psychosocial and cultural
factors: if good expectations of elders,
good memory
HARDWARE OF MEMORY
 There are several memory systems
 These systems are anatomically different
 They are involved in acquiring and
storing different kinds of information
Currently studied using
 MRI: magnetic resonance imaging
 fMRI: functional MRI, taken during brain
activity
 PET: positron emission tomography
 EEG: electroencephalograph: still used
BIOPHYSIOLOGICAL UNDERPINNINGS
OF MEMORY:
 HIPPOCAMPUS and other structures in
the medial temporal lobe. “Old brain”
 FRONTAL LOBES: executive function
 Hippocampus crucial for memory
formation – except unconscious memory
formation.
 Hippocampus forms and activates
cortical connections
 Once memories are well stored,
hippocampus not necessary for recall
THE HUMAN BRAIN
THE LIMBIC SYSTEM
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With related structures in the cortex, it
acts like a switchboard, controlling the
ability to remember many kinds of
declarative information
Is vital to the encoding functions of
working memory
Its role is temporary
Is involved in the creation and immediate
retrieval of new memories
Loses an estimated 20% of its nerve
cells with advancing age
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Particularly vulnerable to injury from
changes in blood pressure that often
occur during adulthood and to stress
If older adults suffer hippocampal
deterioration, the alertness,
concentration, and organizational
abilities needed to process new
information efficiently may decline
Recall of prior learning (independent of
the hippocampus) may improve as a
result of the growing complexity of neural
connections in the cortex
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A continuous stream of stress hormones
appears to affect the hippocampus,
reducing performance on tests of
attention and memory
Encodes consciously perceived
information rapidly, almost automatically,
and without organization
Hippocampal deterioration can be due to:
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blood pressure problems
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stress
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oxygen deprivation
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accumulation of lipofuscin
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insufficient stimulation
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decrease in neurotransmitters production
Affects:
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alertness
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attentional factors
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concentration
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organization
Works in conjunction with the RAS (reticular activating
system)
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Non-declarative memory (motor skills,
habits) are not dependent on the
hippocampus. Instead, on the cerebellum
and neostriatum
Emotional responses: amygdala.
Independent from conscious memory
systems
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Frontal lobes: front portions of the
brain’s cerebral cortex, which form and
direct strategies for encoding, storage,
and retrieval of memories
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Play a role in both normal and
pathological memory changes
They coordinate, interpret, and elaborate
information to provide proper instructions
for encoding and retrieval
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It is the operations of this strategic frontal
system that you are aware of in
searching your memory
They constantly evaluate the output of
the hippocampal system
Evidence implicates the frontal lobes in
selective declines in normal cognitive
functioning
The ability to remember when and where
you learned something seems to be
related to the functioning of the frontal
lobes
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Learning that requires organization and
elaboration is related to the frontal lobes
Damage does not usually hamper
learning of information that can be
encoded without creating new categories
or associations
Loss of neurons in the frontal lobes
(50%) may be related to commonly
observed deficits in working memory in
older adults
Help focus attention and inhibit irrelevant
responses
Structures Controlling
Unconscious Memory
Perceptual and motor skills seem to depend
on the neostriatum.
Neostriatum: a subcortical structure above
the hippocampus, which controls motor
activity
Muscular conditioning or changes in heart
rate due to conditioned fear appears to
be linked to the cerebellum.
Cerebellum: the brain’s coordinating center
for muscular activity, which lies below the
cortex near the back of the head.
Tricks memory can play:
1. Source memory:
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False memory:
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Where did I hear this? who told me? Older
adults less accurate.
Remembering things that didn’t happen.
Older adults higher incidence. Con artists
take advantage.
Due to not trusting one’s memory?
Not remembering information that
conflicts with previously held beliefs.
More pronounced in older adults.
Importance of memory self-efficacy:
 Belief in one’s memory capacity.
Influences actual performance in
memory tasks and determines whether
older adult retreats from new
situations/tasks or not.
Memory and Mental Health:
 Stress
 Depression
memory deficits
 Dementia
Memory and Drugs:
 Alcohol
 Tranquilizers and sedatives
 Antipsychotic drugs
memory deficits
Memory and Nutrition:
 Vitamin B complex: very important for CNS
(central nervous system)
Memory and Physical Exercise:
 More oxygen to brain
 More endorphins: mood enhancer, helps
cognitive function, increased confidence
Long-term Memory: Inactive Storage
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Not all contents within the long-term
memory are equally accessible
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Long-term memory is divided into
“rooms” with different kinds of contents,
and aging affects them differently
Metamemory: The View From Within
Metamemory: beliefs or knowledge about
how memory works
Related to metamemory: mnemonics
Mnemonics: Making the Most of Changing
Memory
Mnemonics: strategies to enhance encoding,
storage, and recall
 May help adults make the most of changing
memory
E-I-E-I-O model: model for classifying mnemonic
techniques according to type of processing
(explicit or implicit) and initial site of storage
(external or internal)
 Allows us to be precise about which storage
sites and which memory processes are being
tapped
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Explicit External Aids
Devices outside the person that assist
with conscious learning or retrieval of
facts
Notes, lists, calendars
Written reminders are the most popular
(for all ages)
Particularly helpful to older adults to
supplement limited or declining attention
and storage space in working memory
Sensory or object cues can compensate
for the blurring of episodic memory
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Explicit Internal Aids
Mental imaging
A more common use of visual images is
in remembering names
Older adults are less likely than younger
adults to use such imaging strategies
spontaneously
When used by older adults, images tend
to be relevant to their experience rather
than “made-up”
Method of loci: a series of places (loci) are
associated with items to be remembered and
then mentally revisited during recall
 Works for prospective actions
 Rehearsal, organization and elaboration are
explicit internal aids
 Takes conscious effort on the part of working
memory
 Are more useful to younger adults than to older
ones
 Older trainees show less improvement,
especially for different tasks
 Without monitoring and support, older adults
tend to stop using the techniques (effort may
be too great)
Implicit External Aids
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Sensory cues offer promise for improving
implicit memory in older adults
(especially those with memory
impairments) e.g. labelling cupboards
Implicit Internal Aids
 Other memories can be effective for
older adults (especially those with
memory impairment whose unconscious
memory functioning is likely to be
relatively intact) e.g. ironing, showing by
doing
Spaced retrieval: involves priming or
classical conditioning in which people are
trained to recall information for an
increasingly long time
 Has proved effective with Alzheimer’s
patients
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Forgetting and its Surprising Benefits
Difference between human beings and
computers is the ability to forget
Memory is a dynamic, ever changing synthesis
of remembering and forgetting
Forgetting clears the way for freshness,
creativity, and innovation
Forgetting: the mind’s overflow valve
A mind that couldn’t forget would contain an
indiscriminate jumble of the important and
unimportant, the relevant and irrelevant
Difficulty generalizing (a person who couldn’t
forget details)
Forgetting and its Surprising Benefits (Cont.)
 Older people may be more likely to forget in
everyday life
 Older people may shift to a strategy of
selective forgetting so they can use their
mental energy and attention more efficiently for
the tasks that matter at their time of life
 From a lifespan perspective, forgetting may be
the price for a developmental change that
enables wisdom to emerge
Summing up: Memory and Age
 Information-processing theory and
research suggest that memory is a highly
complex set of processes and storage
systems
 Aging does negatively affect the capacity
of working memory to process certain
kinds of declarative information and to
access it in long-term memory
 Older adults may have less attentional
resources to focus on manipulating
information and may not use the most
effective strategies for encoding it
Summing up: Memory and Age (Cont.)
 After years of living, recollection of
specific episodes begins to fade and
events tend to run together in memory
 The ability to call on general knowledge
increases (the ability to express it
verbally may not)
 Unconscious remembering, usually of
skills or procedures, generally holds up
well with age
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The Art of Aging
The Best Memory Aid:
A Healthy Lifestyle
Cigarette smoking has negative effects
on complex problem solving that makes
high demands on working memory and
long-term memory
Getting enough sleep and eating the
right foods can make a positive
difference in how well memory works
across the adult lifespan
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REM sleep is an important time for
consolidation of new learning
Aspartame, and artificial sweeteners, contains
phenylalanine, the amino acid involved in
phenylketonuria (PKU), an enzyme disorder
than can cause developmental disabilities
An excess of diet soda can impair mental
performance, especially when accompanied by
other sweets
Zinc is crucial to nerve cells in the cortex that
control memory and high-level thinking but
Too much zinc can be toxic and may be
associated with Pick’s disease
The Multicultural Context
Memory and Culture
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People tend to remember what they are
familiar with and interested in
People’s knowledge base, which
influences what they remember, varies
from culture to culture
Adults tend to excel in the skills which
their culture encourages