Chapter 5: Memory: Models and Research Methods

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Chapter 5 Memory Models and Research Methods
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Some Questions of Interest

• What are some of the tasks used for studying
  memory?
• What is the traditional model of memory? What are
  some of the alternative models?
• What have psychologists learned by studying both
  exceptional memory and the physiology of the
  brain?

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But first, a test!

• Lets generate some words

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Processes in Memory

• Encoding
• Storage
• Retrieval

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Which type of test would you rather have?

• An essay or a multiple-choice exam?

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Demonstration

• The 7 Dwarfs

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Methods Used to Study Memory

• Recall
• Serial recall
• Free recall
• Cued recall
• Recognition
• ? these are explicit memory tasks

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Implicit memory

• Remember priming?
• Procedural memory, too

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Implicit Memory Tasks

• Participants are exposed to a word list
• Tiger
• Lion
• Zebra
• Panda
• Leopard
• Elephant
• After a delay

• Participants then complete word puzzles they are
  not aware this is a type of memory test
• Word fragment completion
• C_E_TA_
• E_E_ _A_ N_
• _ E _ R A
• Word stem completion
• Mon _____
• Pan_____

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Procedural Memory

• Knowing how to do something
• Ride a bike
• Skateboard
• Ski

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Methods to Assess Procedural Memory

• Rotary-pursuit task
• Keep stylus on a dot on a rotating disk
• Mirror-tracing task
• Watch mirror image to trace a figure

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Models of Memory

• Represent ways that memory has been
  conceptualized
• Atkinson Shiffrins three-stage model
• Craik Lockharts level of processing model
• Baddeleys working memory model
• Tulvings multiple memory systems model
• McClelland Rumelharts connectionist model

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Traditional Model of Memory

• Atkinson Shiffrin (1968) three-stage model

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Sperling Sensory Memory Demonstration CogLab
Partial Report

• A matrix of 12 letters and numbers briefly flash
  on the next few slides
• As soon as you see the information, write down
  everything you can remember in its proper
  location

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Sperlings Results
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Averbach Coriell (1961) Iconic Memory Research
N M L C W D P Q A X I N Y K J U

• - Showed matrix for 50 msec
• - Placed a small mark above a letter at different
  delays
• Found that as many as 12 letters could be stored
  in
• sensory memory
• Backward visual masking was also discovered with
  this technique

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Second Demonstration
G E U L M F S X W P M B D H J Y

• - Showed matrix for 50 msec
• - Placed a small mark above a letter at different
  delays
• Found that as many as 12 letters could be stored
  in
• sensory memory
• Backward visual masking was also discovered with
  this technique

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Sensory Stores

• Iconic store or visual sensory register
• Holds visual information for 250 msec longer
• Information held is pre-categorical
• Capacity up to 12 items
• Information fades quickly
• Econ or auditory sensory register
• Holds auditory information for 2-3 seconds longer
  to enable processing

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Short-Term Memory
Rehearsal

• Attention
• Attend to information in the sensory store, it
  moves to STM
• Rehearsal
• Repeat the information to keep maintained in STM
• Retrieval
• Access memory in LTM and place in STM

Short-Term Memory (STM)
Attention
Storage Retrieval
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Demonstration STM span
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Research on Short-Term Memory

• Miller (1956)
• Examined memory capacity
• 7/- 2 items or chunks
• Chunking organize input into larger units
• 1 9 8 0 1 9 9 8 2 0 0 3 - Exceeds capacity
• 1980 1998 2003 - Reorganize by chunking

College graduation
Birth year
HS graduation
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Long-Term Memory

• Capacity
• Thus far limitless
• Duration
• Potentially permanent

Long-Term Memory (LTM)
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Bahricks Research on Very Long-Term Memory

• High school yearbooks containing student names
  and photos
• 392 high school graduates (17-74) took four
  different memory tests
• For some of the participants, it was as long as
  48 years since they graduated

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Bahrick et al. (1975) Results

• 90 accuracy in face and name recognition after
  34 years
• 80 accuracy for name recognition after 48 years
• 40 accuracy for face recognition after 48 years
• 60 accuracy for free recall after 15 years
• 30 accuracy for free recall after 30 years

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Levels of Processing Model of Memory

• Craik Lockhart (1972)
• Deep processing leads to better memory
• Elaborating according to meaning leads to a
  strong memory
• Shallow processing emphasizes the physical
  features of the stimulus
• The memory trace is fragile and quickly decays
• Distinguished between maintenance rehearsal and
  elaborative rehearsal

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Support for Levels of Processing

• Craik Tulving (1975)
• Participants studied a list in three different
  ways
• Structural Is the word in capital letters?
• Phonemic Does the word rhyme with dog?
• Semantic Does the word fit in this sentence?
  The ______ is delicious.
• A recognition test was given to see which type of
  processing led to the best memory

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Craik Tulving (1975) Results
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cogLab levels of processing
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Self-Reference Effect

• Rogers, Kuiper, Kirker (1977)
• Encoding with respect to oneself increases memory

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Baddeleys Working Memory Model
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Working Memory Model

• Phonological Loop
• Used for acoustic rehearsal
• Visuo-spatial sketch pad
• Used for visuo-spatial information
• Episodic buffer
• Used for storage of a multimodal code, holding an
  integrated episode between systems using
  different codes
• Central executive
• Focuses attention
• Plans sequence of tasks, switches attention
  between different parts

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Working Memory Model Support

• Baddeley (1986)
• Participants studied two different list types
• 1 syllable wit, sum, harm, bay, top
• 5 syllables university, opportunity, aluminum,
  constitutional, auditorium

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Working Memory Model Support

• Visuo-spatial sketch pad
• Dual-task paradigm
• Sketchpad can be disrupted by requiring
  participants to repeatedly tap a specified
  pattern of keys or locations while using imagery
  at the same time

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Neuroscience and Working Memory
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Tulvings Multiple-Memory Systems Model

• Semantic memory
• General knowledge
• Facts, definitions, historical dates
• Episodic memory
• Event memories (first kiss, 6th birthday)

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Multiple-Memory Systems Model Support

• Nyberg, Cabeza, Tulving (1996)
• Asked people to engage in semantic or episodic
  memory tasks while being monitored by PET  
• Results 
• Left (hemisphere) frontal lobe differentially
  active in encoding (both) and in semantic memory
  retrieval
• Right (hemisphere) frontal lobe differentially
  active in retrieval of episodic memory

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Connectionist Perspective

• Parallel distributed processing model
• Memory uses a network
• Meaning comes from patterns of activation across
  the entire network
• Spreading activation network model
• Supported by priming effects

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Exceptional Memory

• Case studies of mnemonists
• Studies of skilled memory

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Memory Movies

• Take any character from a movie who has a memory
  deficit, and, using terms from the chapters,
  explain what the memory problem is and why it
  occurs
• Johnny Mnemonic 50 First Dates Memento Total
  Recall Bourne Identity Dark City Manchurian
  Candidate Overboard The Changeling Eternal
  Sunshine of the Spotless Mind The Majestic
  Mulholland Drive The Notebook Paycheck
  Sommersby The Vow

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Case Studies

• S. (Luria, 1968)
• Long strings of words
• Remembered over 15-18 years
• Rajan Mahadevan
• Can recite pi to 31,811 places
• No forgetting on matrices up to 20 x 20 digits

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Deficient Memory

• Amnesias
• Retrograde amnesia
• Loss of memory for events that occurred before
  the trauma
• Infantile amnesia
• Inability to recall events of young childhood
• Anterograde amnesia
• No memory for events that occur after the trauma

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Amnesia Studies

• Amnesiacs show normal priming (implicit), but
  poor recognition memory (explicit)
• They did not remember having seen the word list,
  but completed the word fragments at the same rate
  as normals

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Hippocampus and Memory

• Critical for integration and consolidation
• Essential for declarative memory
• Without the hippocampus, only the learning of
  skills and habits, simple conditioning, and the
  phenomenon of priming can occur

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Alzheimers Disease

• Symptoms (gradual, continuous, and irreversible)
• Memory loss
• Problems doing familiar tasks
• Problems with language
• Trouble knowing the time, date, or place
• Poor or decreased judgment
• Problems with abstract thinking
• Misplacing things often, such as keys
• Changes in mood, behavior, and personality
• These symptoms could be an early sign of
  Alzheimers when it affects daily life

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Alzheimers Disease and the Brain

• Atrophy of the cortical tissue
• Alzheimers brains shows abnormal fibers that
  appear to be tangles of brain tissue and senile
  plaques (patches of degenerative nerve endings)
• The resulting damage of these conditions may lead
  to disruption of impulses in neurons