Download INTRODUCTION TO PSYCHOLOGY

INTRODUCTION TO
PSYCHOLOGY
Chapter 7
Memory
At the end of this Chapter
you should be able to:
• Understand what memory is
• Learn about working memory and long term
memory
• Learn about three aspects of memory;
acquisition, storage and retrieval
• Understand what happens when memory fails
Memory
• Without memory....
– No recollection of events
– No knowledge
– No reflection of past events; no
giving advice to others
– No basis for self-esteem and mood
– No idea about past achivements
Acquisition, Storage,
Retrieval
• Any act of memory requires success at
three aspects:
– Input, or the acquisition of knowledge
- Acquisiton
– Creation of a memory trace, or the
storage of knowledge - Storage
– Ability to use the knowledge Retrieval
• Recall / Recognition
Acquisition
• Includes any instance of new intentional
(like memorizing) or incidental learning
– Incidental: What did you have for
dinner yesterday? You didn’t
memorize, but you know
• Attention and engagement with to-beremembered material is crucial;
acquisition is not passive or “cameralike”
The Stage Theory of
Memory
• Different types of memory, each with
different properties
–Working memory (Short-term)
• Instantly accessible information
– Long-term memory
• Less instantly accessible
Working Memory / Long
Term Memory
When we are actively working, we want
information to be immediately available
to us. In our brain, this happens in
Working (short-term) Memory.
Long Term Memory is for extra
information. It contains everything you
know. It is storage for information that is
not used right now but may be needed
later.
Storage Capacity of
Working and Long-term
memory
• Long-term memory capacity: huge
• Working memory capacity: more modest
• Memory span: way of measuring working
memory capacity
– Random, unrelated information: we can store
about 7, plus or minus 2, items (5 – 9 items)’
– Referred to as “the magic number 7”
Working Memory
• “Loading platform” analogy
• Long term memory must be “loaded” or
“pass through” WM
• How does it move? How is it transformed
into Long term memory?
– Rehearsed
– Chunked
• Primacy Effect
• Recency Effect
Chunking
• Working memory can only handle a small
number of items at one time. However what
these packages contain can be up to us.
149162536496481
Can you remember all of these digits?
Chunking
• If you look at these digits independently,
you will fail to remember them!
• What about if you organize them
differently?
1 4 9 16 25 36 49 64 81
Now you only have to remember the
relationship between these items. So
working memory’s capacity is dependent on
these chunks, not independent items.
Active memory and
organization:
A changed emphasis
• Learner’s activities must be considered
when examining memory
– Maintenance rehearsal
• Primacy / Recency Effect
– Processing and organizing information:
the “Royal Road into Memory”
– Do you know whose picture is on 5 TL?
Athough people see
5 TL many many
times, they seem to
have little
recollection of it’s
layout
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Depth of processing
• Deep processing:
– Meaning-based attention
– Anything that connects new information
to already-learned material
– Material that “makes sense” will be
encoded more efficiently
– Results in superior recall
Depth of processing
• Memory connections:
– Links among ideas
– Abstract similarities
• When the time comes to recall
something, these connections,
established during initial learning or
acquisition, can be used as retrieval
paths.
• Mnemonics
– “Method of loci”
– Based on
rhythm/rhyme/melody/visualization
A
B
Research participants shown related
elements, such as a doll sitting on a chair
and waving flag (A), are more likely to
associate the words doll, flag and chair
than participants who are shown the three
objects next to each other but not
interacting (B).
Storage
• Once encoded, must be stored until
needed
• Record (stored memory): memory
trace or the engram
• Storage process difficult to research:
But: a memory is NOT stored in a
single location: different aspects of a
memory can be stored in different
brain structures
Consolidation
Memory traces are not created instantly. A
period of time is needed after the
experience to become established in
memory. This makes memories permanent.
(You need to sleep in order for this to take
place!!!!)
• Evidence for consolidation?
– Retrograde amnesia: a blow to the head
can interrupt the process of consolidation
for events that happened 1-2 hours
before the accident occurred
– Memory for events during that time
period is lost
Retrieval
• Storage is not enough; we must be
able to access the memory when
needed
• Inadequate coding  failure to
retrieve
• With an adequate retrieval cue,
sometimes we realize that encoding
wasn’t the problem after all. Like, if
you see the person’s face, you’ll
remember their name. A word or a
smell may help you remember. These
are all cues (hints).
Retrieval cues
• Context reinstatement
– Re-creating or re-minding oneself of
the context in which one originally
learned something increases
likelihood of being able to retrieve it
later
Example: Studying for an exam in
the same room you will take the
test; returning to your hometown
and remembering things you had
“forgotten”
Memory failures
• Inadequate encoding: Forgetting can
often be traced to poor or missing
strategies for encoding
• Forgetting: we knew it once, but no
longer
– Passage of time
– Can be graphed with a “forgetting
curve” – the opposite of a “learning
curve”
• Ebbinghaus: Memory declines
with time, more sharply at first,
then more gradually
Memory failures
• Decay: a process that occurs on a
cellular level by normal metabolic
“wear and tear” on cells involved with
memory
• Interference: New learning interferes
– independent of the passage of time
– Passage of time not a powerful
factor in explaining forgetting
– Number of intervening events are
more useful variable to examine to
explain forgetting
Other retrieval errors
Retrieval failure:
One type: the “tip of the tongue”
phenomena
Who was the famous American
basketball player who wore “23”
as a uniform number?
Who was the man who played
in the movie “Psycho”, with a
knife in his hand in the shower
scene?
Misinformation Effect
Imagine you eye witnessed a crime and see
the thief flee in a blue car. The next day,
you read a newspaper account of the same
crime and learn that another witness
reported that the thief fled in a green car.
How will this new information influence your
memory?
The errors we make can be very large.
People can be led to remember cars that
were not actually present in an event, and
whole buildings that do not exist. They can
even recall events that never happened.
Misinformation Effect
• It is common to ‘remember’
things that never happened.
• Example of this is experiment
by: Wade, Garry, Read, &
Lindsay (2002)
• People were shown
photographs of themselves in
a hot-air balloon and asked
what they remembered. Most
people remembered the
experience. But the photos
were made using photoshop.
The people had never been in
a hot-air balloon
Misinformation Effect
Misinformation can be used to insert
new ideas into memory. In these
cases the original memory may even
be lost because the person who is
given the misinformation (new
information about an event that
happened) overwrites the original
memory with the fake one.
More (!) retrieval errors…
• Intrusions from general knowledge
• Misplaced familiarity
– Difference between recollection
memory and familiarity
Big problem for us: No reliable way to
tell “good” memories (accurate) from
“bad” memories (those that are false
or contain misinformation or
inaccuracy)
Techniques for improving
memory
• How to help us create better
memories?
– Techniques for improving
“eyewitness identifications” that are
more reliable:
• Re-create mind-set
• Minimize distractions/distractors
– Unhelpful techniques:
• Hypnosis
Amnesia : Memory Loss
• Different brain tissue supports implicit
memories as compared to explicit
memories
• Evident when studying anterograde
amnesia
– Lesions in hippocampus and temporal
cortex: create anterograde amnesia
– Lesions from other types of brain
injury: create retrograde amnesia
Supports the theory that different brain
structures/regions “handle” different
types of memory
Retrograde amnesia
• Forgetting the
past, but being
able to make new
memories.
Soldiers are
sometimes unable
to remember their
experiences in
battle-even the
ones that occured
a day before.
Anterograde Amnesia
Anterograde means ‘in a forward
direction’. May be caused by a stroke
or a physical trauma.
It is essentially an inability to learn
anything new/make new memories.
Anterograde Amnesia
Famous case; Patient H.M.
He could read and write. His longterm storage is completely closed
to new memories. His memories
before the operation remain
intact. He can function and
comment intellectually on events.
Anterograde Amnesia
What is wrong with H.M.?
He had an uncle that he really loved. His
uncle passes away and then he is told
about the death of his uncle. He was
deeply distressed when told about this,
but the he forgot! Some time later he
would ask where his uncle was, and was
again told about his death. His sadness
and grief was just as intense as before
each time he hears this sad news. He
said he is hearing it for the first time-with
all the shock and grief.
Anterograde Amnesia
It turns out these anterograde amnesia
patients can acquire some new memories.
For example H.M. plays the piano and each
time he plays a piece, he plays it more
skillfully.
Distinction between different types of
knowledge: memory for skill, memory for
general knowledge, memory for episodes.
KNOWING HOW vs. KNOWING WHAT
Emotional Remembering
• Does memory for emotional events
differ in any systematic way?
• Emotional events: remembered…
– More vividly
– More completely
– More accurately
… than memories for emotionneutral events
“Flashbulb memories”
• Especially vivid memories
• Focus: immediate and personal
details
• Special mechanism to produce
this type of memory?
No evidence that these types of
memories are in a special class
with respect to immunity from
error or extreme longevity
“Flashbulb memories”
They are likely to involve people we
love and care about.
Some emotional memories are
particularly long-lived, so that
people claim to remember events
from years and years ago “as if it
were yesterday”.
“Flashbulb memories”
Flashbulb memories are highly special
events, usually unexpected and
emotionally strong. Such as 9/11
terrorist attacks to the World Trade
Center, or Princess Diana’s death.
Where and who were you with when
you first heard these events? Most
people remember all the details…