MEMORY
Phenomenon of Memory
• Memory – the persistence
of learning over time
through the storage and
retrieval of information
Phenomenon of Memory
• Information Processing
Model – like a computer,
our brain encodes (gets info
into brain), stores (retains
info there), and retrieves
(later gets info out)
information from memory
• The brain is slower than a
computer, but can perform
many more tasks at once
Information Processing Models
Information Processing Models
• Connectionism – a modern
model of info processing, it
views memories as
emerging from
interconnected neural
networks
• Atkinson and Shiffrin (1968)
had the following
(somewhat limited)model:
– Specific memories result from
different activation patterns
within these networks
– 1. Sensory Memory: contains
“soon-to-be-remembered”
info
– 2. Short-Term Memory: next
step where info is encoded
through rehearsal
– 3. Long-Term Memory: info
is eventually stored for later
retrieval
Information Processing Models
• Modifications to earlier
model:
– 1. Some information is
processed directly into longterm memory
– 2. Working Memory (ShortTerm Memory) concentrates
on the active processing of
information; it associates new
and old information and
solves problems
Encoding: Getting Info In
• Automatic Processing –
unconscious encoding of
incidental information, such
as space, time, and
frequency, and of welllearned information, such
as word meanings
– Info related to space, time,
frequency, and well-learned
info occurs automatically
Encoding: Getting Info In
• Effortful Processing –
encoding that requires
attention and conscious
effort
– Often produces durable and
accessible memories
• Rehearsal – conscious
repetition of information,
either to maintain it in
consciousness or to encode
it for storage
Encoding: Getting Info In
• Hermann Ebbinghaus
(1850-1909) – German
philosopher who discovered
the amount of information
remembered depends on
the time spent learning;
– over learning increases
retention
– practice makes perfect
• “Ebbinghaus Retention
Curve”
Encoding: Getting Info In
• “Those who learn quickly
also forget quickly.”
– Hermann Ebbinghaus
• Spacing Effect – distributed
study or practice yields
better results than does
massed study or practice
Encoding: Getting Info In
• Testing Effect – repeated
quizzing of previously
studied material helps in
retaining information longer
• Serial Position Effect – our
tendency to recall best the
last and first items in a list
– Primacy Effect – first items
– Recency Effect– last items
What We Encode
• When encoding, our
working memories interact
with our long-term
memories
• Visual Encoding – images
• Acoustic Encoding – sounds
• Semantic Encoding –
meanings (*best type of
encoding to help remember
words later)
What We Encode
• Compared with learning
nonsense syllables, learning
meaningful material
required 1/10 the effort
according to Ebbinghaus
• Amount of information
remembered depends on:
– Time spent learning
– Your making it meaningful
What We Encode
• Self-Reference Effect –
information deemed
“relevant to me” is
processed more deeply and
remains more accessible
What We Encode
• Our earliest memories
(from age 3-4) involved
visual imagery
• When we encode things
both semantically and
visually we tend to
remember them better;
two codes are better than
one
What We Encode
• Rosy Retrospection: recalling
the high points while
forgetting the mundane
• Mnemonics – memory aids,
especially those techniques
that use vivid imagery and
organizational devices
– Peg word system pairs a
number with a rhyming name:
one is bun, two is shoe, etc.
What We Encode
• Chunking – organizing items
into familiar, manageable
units; often occurs
automatically (usually seen
as letters, words, or
phrases)
• We all remember
information best when we
personally organize it into
meaningful arrangements
What We Encode
• Chunking (acronyms)
– ROYGBIV = red, orange,
yellow, green, blue, indigo,
violet
– HOMES = Huron, Ontario,
Michigan, Erie, Superior
• Hierarchies also help to
organize information
– Hierarchies = layered
information
What We Encode
• Organize and group what
you study; you will retain it
better
Storage: Retaining Information
Storage: Retaining Information
• George Sperling (1960) –
showed that we all have a
temporary photographic
memory called iconic memory
• Iconic Memory – a momentary
sensory memory of visual
stimuli; a photographic or
picture-image memory lasting
no more than a few tenths of a
second
• Echoic Memory – a
momentary sensory
memory of auditory stimuli;
if attention is elsewhere,
sounds and words can still
be recalled within 3 or 4
seconds
– Auditory echoes tend to
linger for 3-4 seconds
Working/Short-Term Memory
• Unless working memory
meaningfully encodes or
rehearses information, it is
quickly lost
• Without active processing,
short-term memories have
a limited life
Working/Short-Term Memory
• George Miller’s (1956)
Magical Number Seven
(plus or minus two) –
number of bits of
information capable of
being stored in our STM
Working/Short-Term Memory
– Our short term recall is better
for random digits than for
letters
– Better for what we hear than
what we see
• Recall as many words as we
can speak in 2 seconds
– Short-term memory can hold
fewer signs (sign language)
than spoken words
– We can only retain about 4
information chunks without
rehearsal
Long-Term Memory
• Our capacity for storing
long-term memories is
essentially limitless
• Memories DO NOT reside in
single, specific spots
• Elizabeth Loftus (1980) –
said “our whole past is not
IN THERE” in reference to
the brain; we invent or
reconstruct memories
Storing Memories in the Brain
• Increased synaptic efficiency
makes for more efficient
neural circuits
– Sea Slug releases more
serotonin at synapses, making
signal transmission efficient
• Long-Term Potentiation (LTP) –
an increase in a synapse’s
firing potential after brief,
rapid stimulation. Believed to
be a neural basis for learning
and memory.
Memory Boosting Drugs
• Boost protein CREB, which
can switch genes off or on
• With repeated neural firing,
a nerve cell’s genes produce
synapse-strengthening
proteins enabling LTP
• Sea slugs, mice, fruit flies
with enhanced CREB have
enhanced memories
Memory Boosting Drugs
• Glutamate – a
neurotransmitter that
enhances synaptic
communication (LTP)
• Sleep is still a great memory
enhancer (Study followed
by sleep is best)
Memory
• ECT – Electroconvulsive
Therapy – biomedical therapy
for severely depressed
patients where a brief electric
current is sent through the
brain of an anesthetized
patient
– Most recent memories are lost;
working memory had no time
to consolidate information into
long-term memory
– Similar to getting knocked out
Stress Hormones
• When excited or stressed,
emotion-triggered stress
hormones make more
glucose available to fuel
brain activity, signaling the
brain that something
important has happened.
Stress Hormones
• Amygdala boosts activity
and available proteins in
brain’s memory-forming
areas.
• Memory of neutral events
around the same time are
disrupted
Stress Hormones
• Stronger emotional
experiences make for
stronger, more reliable
memories
• Weaker emotions mean
weaker memories
Stress Hormones
• Flashbulb memories – a
clear memory of an
emotionally significant
moment or event
– Very vivid; usually recalled
with great detail
– Misinformation may seep into
them
• Hippocampus – brain area
vital for laying down
memories
Stress Hormones
• When stress hormones are
flowing, older memories
may be blocked
– Ex. – public speaking
• Amnesia – the loss of
memory
Memory
• H.M. – famous case of 1953
man who had brain area
responsible for laying down
new memories surgically
removed
– Still had access to older
memories
– No ability to remember new
things
– Still have a capacity to learn;
although they demonstrate
learned things with no
awareness of having learned
them (Ex. Where’s Waldo)
Implicit vs Explicit Memory
• Implicit Memory
(Nondeclarative Memory)–
retention independent of
conscious recollection
– “Without conscious recall”
– Processed by other brain areas,
including cerebellum
– Skills (cognitive & motor)
– Classical Conditioning
– Patients with amnesia may
learn “how” to do something,
but may not know how they
know, or may not be able to
“declare” what they know
Implicit vs Explicit Memory
• Explicit Memory
(Declarative Memory) –
memory of facts and
experiences that one can
consciously know and
“declare”
–
–
–
–
“With conscious recall”
Processed in hippocampus
Facts (general knowledge)
Personally experienced
events
Forming New Memories
• Even Alzheimer’s patients
have the ability to form new
implicit memories
• Hippocampus – found in
temporal lobe, part of
limbic system; where
explicit memories of names,
images, and events are laid
down
Forming New Memories
• Hippocampus is lateralized
– you have two of them
• Damage to Right Hipp.
– No trouble with verbal info
– Trouble with visual designs
and locations
• Damage to Left Hipp.
– Trouble with verbal info
– No trouble with visual designs
and locations
Memory
• Hippocampus is active
during slow wave sleep
• The greater the
hippocampus activity during
sleep after a training
experience, the better the
next day’s memory
• Sleep supports memory
consolidation
Memory
• During sleep, both the
hippocampus and cortex
display activity
– Brain is probably replaying
activities of previous day and
info is transferred to cortex
for long-term storage
Cerebellum
• Cerebellum – extends out
from the rear of the
brainstem
– Plays a key role in forming
and storing implicit memories
– Certain conditioned reflexes
may not be learned with
damage to cerebellum
Memory
• Infantile Amnesia – as
adults we recall nothing
(explicitly) of our first three
years of life
– We index much of our explicit
memory in words, many of
which aren’t yet learned by
age 3
– The hippocampus is NOT fully
developed at age 3, and is
one of last brain structures to
mature
Retrieval: Getting Information
Out
Retrieval: Getting Information
Out
• Recall – a measure of
memory in which the
person must retrieve
information learned earlier,
as on a fill-in-the-blank test
• Recognition – a measure of
memory in which the
person need only identify
items previously learned, as
on a multiple choice test
• Relearning – a measure of
memory that assesses the
amount of time saved when
learning material for a
second time
– If you once learned
something and then forgot it,
it will be learned more quickly
the second time
– We remember more than we
can recall
Retrieval Cues
• Memories are held in
storage by a web of
associations
• Retrieval Cues are anchor
points used to help recall
information later
• Priming – the activation,
often unconsciously, of
particular associations in
memory
Priming Example
• Ask a friend two rapid-fire
questions:
• a)How do you pronounce
the word spelled by the
letters s-h-o-p?
• b)What do you do at a
green light?
• *If your friend answers
“stop”, you have
demonstrated priming
Context Effects
• Putting yourself back in the
context where you
experienced something can
prime your memory retrieval
• Déjà Vu – the eerie sense that
“I’ve experienced this before.”
Cues from the current
situation may subconsciously
trigger retrieval of an earlier
experience.
Context Effects
• Another theory on déjà vu:
– Information processing occurs
on multiple tracks; if one of
the tracks lags behind
another it may create an
illusion that we are now
experiencing something again
Moods and Memories
• Specific emotions may
prime us to recall events
associated with that
emotion
• What we learn in one state
– drunk or sober - is more
easily recalled when again
in that state (statedependent memory);
although alcohol
significantly disrupts storage
Moods and Memories
• Mood-Congruent Memory –
the tendency to recall
experiences that are
consistent with one’s
current good or bad mood
– Currently depressed people –
recall being parented in a
negative light
– Formerly depressed people –
recall being parented much
like any other person
Moods and Memories
• Our moods effect on
retrieval helps explain why
our moods persist; we tend
to go in a positive or
negative cycle for a while
Forgetting
• William James – said if we
remembered “everything” we
would be in trouble
– We need to discard the clutter
of useless information
• Jill Price (aka A.J.) – woman
who remembers every day of
her life since she was 14, with
detailed clarity; according to
her, it is like a movie that
never stops running
Forgetting
• Daniel Schacter – memory
researcher who explains the
“Seven Sins of Memory”
Forgetting
• Three Sins of Forgetting
– Absent Mindedness
• Inattention to details leads to
encoding failure
– Transience
• Storage decay over time
(unused information fades)
– Blocking
• Inaccessibility of stored
information (someone’s name
is at the tip of our tongue, but
we can’t get it)
• We don’t have enough
information to locate it in our
memory
Forgetting
• Three Sins of Distortion
– Misattribution
• Confusing the source of
information (putting words in
someone else’s mouth or
remembering dream as real)
– Suggestibility
• Lingering effects of
information creates fake
memory (sex abuse cases)
– Bias
• Belief-colored recollections
(current feelings toward a
friend color recalled initial
feelings)
Forgetting
• One Sin of Intrusion
– Persistence
• Unwanted memories (being
haunted by images of sexual
assault)
Encoding Failure
• Slower encoding helps
explain age-related memory
decline
• Automatic Processing =
where we had dinner
yesterday
• Effortful Processing = terms
for this chapter
Encoding Failure
• Encoding Failure leads to
Forgetting prior to
information reaching the
long-term memory
• Ebbinghaus’ Forgetting
Curve- the course of
forgetting is initially rapid,
then levels off with time
Retrieval Failure: Forgetting
• Proactive Interference
(forward-acting) – the
disruptive effect of prior
learning on the recall of
new information
• Retroactive Interference
(backward-acting) – the
disruptive effect of new
learning on the recall of old
information
Retrieval Failure: Forgetting
• Information attained in the
hour prior to sleep is
protected from Retroactive
Interference because the
opportunity for interfering
events is minimized at that
time of day.
Forgetting
• The hour prior to a night’s
sleep is a good time to
commit things to memory
• The seconds just before
sleep show information
seldom remembered
• Positive Transfer – when old
information can facilitate
learning of new information
(knowing Latin helps you
learn French)
Motivated Forgetting
• People unknowingly revise
their own histories
– We may recall doing things
more than we actually did
once we find out that activity
was “good”
– We may recall ourselves being
more “bold” in a
circumstance that was
actually true
Repression
Repression – in psychoanalytic
theory, the basic defense
mechanism that banishes from
consciousness anxietyarousing thoughts, feelings,
and memories
-Freud’s term
-Most people believe that
repression occurs; “it makes
sense”
-Memory researchers feel it
rarely, if ever, occurs;
Repression
• We can intentionally forget
neutral information, but it’s
difficult to forget emotional
information.
• Forgetting can occur at any
memory stage
Memory Construction
• When trying to remember,
we infer our past from our
stored information PLUS
what we later imagined,
expected, saw, and heard.
• We don’t just retrieve
memories, we reweave
them.
Memory Construction
• Elizabeth Loftus – filmed
traffic accident, showed to
participants, then asked
questions about what they
had seen:
– Used leading words such as
“hit” and “smashed” to
provoke varying memories in
participants
Memory Construction
• Misinformation Effect:
incorporating misleading
information into one’s
memory of an event; leads
many people to
“misremember”
• Imagination Inflation:
repeatedly imagining an
event may create a false
memory not easily
distinguished from truth
Memory Construction
• Visualizing something and
actually perceiving
something activate the
same brain areas
• Source Amnesia: attributing
to the wrong source an
event we have experienced,
heard about, read about, or
imagined (aka Source
Misattribution)
Memory Construction
• We can’t be sure whether a
memory is real by how real
it feels
• We can’t judge reality of a
memory on its persistence
• Memories of REAL events
have more detail
• Memories of FALSE events
usually contain gist of story
Memory Construction
• Hypnotically refreshed
memories easily incorporate
errors
• Cognitive Interview
Technique
– Trained police interviewers
ask witnesses to visualize and
tell about the scene of crime
– Witness tells in detail
– Only then does interviewer
ask more leading questions
Memory Construction
• Example of False Memory:
– Rape victim identified man
closely resembling the
perpetrator. Only later did
victim realize the man was on
a live T.V. interview in the
background of her crime
scene. (source amnesia)
Memory Construction
• Children’s Eyewitness Recall
– Interviewers who ask leading
questions can plant false
memories
– Children often confuse stories
they have heard with actual
memories of REAL events
– Children are most accurate
when they haven’t spoken with
involved adults, when
disclosure is made in first
interview with neutral person,
and when nonleading
questions are used
Repressed or Constructed
Memories of Abuse?
Both Sides Agree on the
Following:
• Trauma survivors are
sometimes disbelieved
when telling their secret
• Innocent people are
sometimes falsely accused
• Families are sometimes
cruelly ripped apart by
accusations based on falsely
reconstructed memories
(also happens to clergy)
•
•
•
•
Sexual abuse happens
Injustice happens
Forgetting happens
Recovered Memories are
commonplace
– Ones that surface naturally are
more reliable
• Memories of events prior to age 3
are unreliable
• Memories retrieved under
hypnosis or influence of drugs are
especially unreliable
• Memories, both real or false, can
be emotionally upsetting
Memory Reconstruction
• People remember clearly
and vividly being abducted
by aliens
• Elizabeth Loftus
“remembered” finding her
mother drowned in pool
(actually her aunt had made
the discovery)
On Repression…
• The most common response
to traumatic experience is
NOT banishment of the
experience to the
unconscious. Rather, such
experiences are typically
etched on the mind as vivid,
persistent, haunting
memories
Improving Memory
• SQ3R Method: Survey,
Question, Read, Rehearse,
Review
• Study Repeatedly
• Make Material Meaningful
• Activate Retrieval Cues
• Use Mnemonic Devices
• Minimize Interference
• Sleep More
Improving Memory
• (continued)
• Test your knowledge, both
to rehearse it and to help
determine what you do not
yet know
– Don’t by lulled into
overconfidence by your ability
to recognize information
– Test your ability to recall
information
Improving Memory
• Actively thinking as we
read, by rehearsing and
relating ideas, yields the
best retention.