Transcript Memory

Memory
• Goal  How do we encode
information for memory?
• Learning Target: Describe memory in
terms of information processing, and
explain the encoding process.
The Memory Process
Three step process….
1. Encoding: The processing of
information into the memory
system.
2. Storage: The retention of
encoded material over time.
3. Retrieval: The process of
getting the information out of
memory storage.
Three Box Model of
Memory
Connectionism
• Modern model of memory
• Views memories as emerging from
interconnected neural networks
• Activation patterns lead to specific
memories within these networks
Info-Processing
• Automatic
– Parallel processing
(brain does many things
at once)
– Remembering space,
time, frequency, welllearned info
• Effortful
– Rehearsal/repetition
Encoding Process
Encoding
Effortful
Automatic
Ebbinghaus
 Ebbinghaus used nonsense syllables
 TUV ZOF GEK WAV
 the more times practiced on Day 1, the fewer
repetitions to relearn on Day 2
• Spacing effect – memory is better for info learned over
time
• Ebbinghaus’
Forgetting Curve
Encoding Information
Serial Position Effect =
• Primacy Effect – better remember items
earliest in a series
• Recency Effect – better memory for items
at the end of a series
The ways we can encode…
• Visual Encoding: the
encoding of picture
images.
• Acoustic Encoding: the
encoding of sound,
especially the sounds of
words.
• Semantic Encoding: the
encoding of meaning.
Levels of Processing
• Shallow processing
– Processing by
encoding the physical
qualities or sounds of
the information
(visual & acoustic
encoding)
– Pure repetition (i.e.
flashcards) – a.k.a.
maintenance
rehearsal
– Short-term retention
• Deep processing
– i.e. Semantic
encoding
– Elaboration rehearsal
(analysis, relating to
prior knowledge)
 Implications for learning & teaching
strategies!
Encoding
 Imagery
 mental pictures
 a powerful aid to effortful processing, especially
when combined with semantic encoding
 Mnemonics
 memory aids
 especially those techniques that use vivid imagery
and organizational devices
 Acronyms
 Method of Loci
 Peg-word system
Encoding
 Chunking
 organizing items into familiar, manageable units
 like horizontal organization--1776149218121941
 often occurs automatically
 use of acronyms
 HOMES--Huron, Ontario, Michigan, Erie, Superior
 ARITHMETIC--A Rat In Tom’s House Might Eat
Tom’s Ice Cream
Encoding: Chunking
 Organized information is more easily
recalled
Encoding
 Hierarchies (Semantic Networks)
 complex information broken down into broad
concepts and further subdivided into categories
and subcategories
Encoding
(automatic
or effortful)
Meaning
(semantic
Encoding)
Imagery
(visual
Encoding)
Chunks
Organization
Hierarchies
• Goal Describe memory in terms of
information processing, and distinguish
among sensory, short-term, and longterm memory.
Storage: Sensory Memory
• Iconic memory
– Brief sensory
memory of images
(tenths of a second)
• Echoic memory
– Brief sensory memory
of sounds (2-4 secs)
Storage: Short-Term (STM)/
Working Memory
Percentage
90
who recalled
consonants 80
70
60
50
40
30
20
10
0
3
6
9
12
15
• Limited duration &
capacity
• Magical number (7+/2 items)
• Events are encoded
visually, acoustically
or semantically.
• We recall digits
better than letters.
18
Time in seconds between presentation
of contestants and recall request
(no rehearsal allowed)
Storage: Long-Term Memory (LTM)
 How does storage work?
 Engrams = physical traces
ofmemories
 Karl Lashley (1950)
 rats learned maze, lesioned
cortexes, retested memory  still
partial memory
 Memories stored throughout the
brain
 Synaptic changes
 Long-term Potentiation
 increase in synapse’s firing
potential after brief, rapid
stimulation
Storage: Long-Term Memory (LTM)
 Strong emotions make for stronger memories =
FLASHBULB MEMORIES
-
Not necessarily more accurate
• Mood-congruent memory  remember when in
same mood as learned/rehearsed
• State-dependent memory  remember when in
same conscious state as learned/
rehearsed
Storage: Long-Term
Memory Subsystems
Types of
long-term
memories
Explicit
(declarative)
With conscious
recall
Facts-general
knowledge
(“semantic
memory”)
Personally
experienced
events
(“episodic
memory”)
Implicit
(nondeclarative)
Without conscious
recall
Skills-motor
and cognitive
Dispositionsclassical and
operant
conditioning
effects
Retrospective Memory
Prospective Memory
 Memory of the past
 Memory for things that
will happen in the future
(i.e. I have a dentist appt.
tomorrow at 3, next week is
my sister’s birthday, etc.)
(i.e. remembering your first
day of school, remembering
the Homecoming dance, etc.)
Storage: Long-Term Memory
 MRI scan of hippocampus (in red)
Hippocampus
Retrieval
• Recall v. recognition tasks
• Relearning - how much less time it takes
to learn material the second time
• Priming - activation of unconscious
associations in memory
Retrieval: Context Effects
• Godden and Baddeley (1975)
Percentage of
words recalled
40
30
20
10
0
Water/
Land/
land
water
Different contexts for
hearing and recall
Water/
Land/
water
land
Same contexts for
hearing and recall
Retrieval: Context & Mood
• Déjà Vu (French)-”already seen”
• cues from the current situation may
subconsciously trigger retrieval of an earlier
similar experience
• Mood-congruent
•
memory  better recall when in same
mood as learned (remember sad things
when sad)
State-dependent
memory  better recall when in same
state of consciousness as learned
Forgetting: Encoding Failure
• Info never gets to LTM (not attended to or
rehearsed)
Attention
External
events
Short- Encoding LongSensory
term
term
memory Encoding
memory
memory
Encoding
failure leads
to forgetting
Forgetting: Storage Decay
Percentage of
list retained
when
relearning
60
 Ebbinghaus
forgetting
curve over 30
days-initially rapid,
then levels
off with time
50
40
30
20
10
0
12345
10
15
20
25
Time in days since learning list
30
Forgetting: Storage Decay
 The forgetting curve for Spanish learned in school
Percentage of 100%
original
90
vocabulary
80
retained
Retention
drops,
70
then levels off
60
50
40
30
20
10
0
1 3 5
9½
14½
25
35½
49½
Time in years after completion of Spanish course
Forgetting: Retrieval Failure
 Forgetting can result from failure to
retrieve information from long-term memory
Attention
External
events
Sensory
memory
Encoding
Encoding
Short-term
Long-term
memory
Retrieval memory
Retrieval failure
leads to forgetting
Forgetting: Interference
• Proactive (forward-acting)
interference  old info
disrupts memory of new info
• Retroactive (backward-acting)
interference  new info
disrupts memory of old info
Forgetting
 Forgetting can
occur at any
memory stage
 As we process
information, we
filter, alter, or
lose much of it
 Repression?
Forgetting- Interference
 Motivated Forgetting (retrieval failure)
 people unknowingly revise memories
 Repression
 defense mechanism that banishes from
consciousness anxiety-arousing thoughts,
feelings, and memories
Amnesia
• Infantile amnesia: difficult to
remember vivid memories from
before ages 2-3
• Dissociative amnesia: inability
to remember
info due to
psychological trauma
Amnesia
• Retrograde amnesia: inability to
remember info before a trauma
• Anterograde amnesia:
inability to remember info after a
trauma
What kind of forgetting?
• Ellen can’t recall the reasons for the WebsterAshburton Treaty because she was daydreaming
in class the day it was discussed.
Encoding failure
• Rufus hates his job at Taco Heaven and is always
forgetting when he is schedule to work.
Retrieval failure (motivated forgetting)
What kind of forgetting?
• Ray’s new assistant in the shipping department is named
Jason Timberlake. Ray keeps calling him Justin, mixing
him up with the singer Justin Timberlake.
Proactive interference
• Tania studied history on Sunday morning and sociology
on Sunday evening. It’s Monday, and she’s struggling
with her history test because she keeps mixing up
prominent historians with influential sociologists.
Retroactive interference
What kind of forgetting?
• Mark was in a near fatal car accident on his way to work.
At the hospital, he cannot remember what he was doing
that morning up until the accident (stopping for coffee,
calling his wife), but still can form new memories.
Retrograde amnesia
• Ally was sexually assaulted, and when reporting the event
has trouble remembering what happened after the assault
(where she went, who she spoke to).
Anterograde amnesia
Memory Construction
 We filter information and fill in
missing pieces
 Misinformation Effect
 incorporating misleading
information into one's memory of
an event
 Source Amnesia
 attributing to the wrong source an
event that we experienced, heard
about, read about, or imagined
(misattribution)
Memory Construction
Depiction of actual accident
 Eyewitnesses
reconstruct
memories when
questioned
Leading question:
“About how fast were the cars
going when they smashed into
each other?”
Memory
construction
Memory Construction
 Memories of Abuse
 Repressed or Constructed?
 Child sexual abuse does occur
 Some adults do actually forget such episodes
 False Memory Syndrome
 condition in which a person’s identity and
relationships center around a false but strongly
believed memory of traumatic experience
 sometimes induced by well-meaning therapists
Memory Construction
 Most people can agree on the following:
 Injustice happens
 Incest happens
 Forgetting happens
 Recovered memories are commonplace
 Memories recovered under hypnosis or drugs are
especially unreliable
 Memories of things happening before age 3 are
unreliable
 Memories, whether false or real, are upsetting
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
 make up story
 chunk--acronyms
Improve Your Memory
 Activate retrieval cues--mentally
recreate situation and mood
 Recall events while they are fresh-before you encounter misinformation
 Minimize interference
 Test your own knowledge
 rehearse
 determine what you do not yet know