Modal Model of Memory

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Modal Model of Memory

• PSY 421 Fall 2004

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Overview

• Methods of conducting memory experiments
• Typical memory findings or results
• Definitions with memory research a summary
• Long-Term Memory and the Serial Position Effect
• Problems for the Modal Model
• Encoding and Retrieval

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Memory Methodology

• The following is the typical procedure for a
  memory experiment
• Stimuli/items (letters, numbers, words, pictures)
  are presented with the instruction that subjects
  are to study these words for a later memory test
  (order of the items may be important)
• A time period passes during which the subject
  must remember the stimuli and may be asked to
  also perform another task (counting backwards,
  viewing unrelated items, solving math problems)

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Memory Methdology, continued

• Subjects are asked to remember the stimuli that
  they studied
• Free Recall test write down all the items from
  the study list that you remember
• Cued Recall test here are some cues to help you
  remember the items from the study list
• Serial Recall test remember the items from the
  study list in the order that you studied them
• Recognition test here are some of the items you
  studied among other items called distractors
  chose the items that you studied (called targets)
• Relearning number of trials to be able to
  remember all the items correctly (Ebbinghaus)
• Reconstruction attempting to remember items and
  other elements associated with the items to
  "rebuild" the original event from memory
• Performance is recorded as accuracy (number of
  items remember correctly), sensitivity (number of
  hits and false alarms from a recognition test),
  or speed (amount of time it takes the subject to
  remember one or all of the items)

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Demos
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Typical Memory Results

• Free Recall subjects remember some but not all
  of the items that they studied (performance is
  better or worse depending upon the type of
  independent variable manipulated (IV))
• Cued Recall subjects remember more items that
  were studied than if they did free recall (but
  performance depends on the IV)
• Recognition easiest of all memory tests,
  subjects remember items well to the extent that
  the targets (studied items) vary from the
  distractors (non-studied items)
• Order of memory when the order of the studied
  items is important, subjects typically remember
  the beginning and the end items better than the
  middle items primacy and recency effects

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Similar Terminology in Memory

• Sensory Memory
• Iconic or Visual Sensory Memory
• Echoic or Auditory Sensory Memory
• Short-Term Memory or Primary Memory or Working
  Memory
• Long-Term Memory or Secondary Memory
• Memory Processes
• Acquisition encoding learning input
• Retention storage holding information
• Retrieval remembering responding output
• Memory Tests
• Explicit Memory Tests Direct Memory tests
• Implicit Memory Tests Indirect Memory tests

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New Definitions

• Long-Term Memory
• Episodic Memory memory for events and
  experiences (including peripheral contextual
  info)
• Semantic Memory memory for knowledge or meaning
  of information
• Other Characteristics
• Duration limitless
• Type of information coding all modalities
• Capacity - limitless
• Serial Position Effect
• Primacy memory for earlier items in a list
• Recency memory for later items in a list
• Encoding taking in information - acquisition

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Serial Position Curve
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Serial Position Effect

• STM and LTM
• Multiple-stores explanation for serial position
  effects (Waugh Norman, 1965)
• Recency occurs because of rehearsal and the items
  at the end of the list are still in STM (dump of
  STM)
• Primacy occurs because beginning items were
  rehearsed the longest and have already been
  transferred to LTM
• STM and LTM are not different (Crowder, 1993
  Nairne, 1992)
• Memory in the short-term is using memory for a
  short period of time memory in the long-term is
  using memory over a longer period of time just
  because we use our memories for different periods
  of time does not mean there are 2 different forms
  of memory
• Primacy effects can still be shown without
  rehearsal
• Recency effects can be found with information
  from LTM (presidents Roediger Crowder, 1976)

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More Problems for the Modal Model

• 1. The modal model predicts that if there is a
  delay between study and test and rehearsal is
  prevent with a distractor task, then recency will
  decrease b/c words that were in STM have faded
  away (or been forgotten) (Glanzer and Cunitz,
  1966).
• Opposing Evidence (Bjork Whitten, 1974) - if a
  distractor activity is added after EVERY item,
  including the final item (called the continual
  distractor paradigm - subjects are continually
  unable to rehearse b/c of distraction), the
  recency effect COMES BACK, even though there was
  no rehearsal for any of the items. For more
  discussion of this topic - see pgs 72-76 of your
  memory text)
• 2. The modal model claims that STM codes
  information on the basis of how it sounds and LTM
  codes information on the basis of its meaning
• Opposing Evidence - there is evidence of
  acoustic interference in LTM (Dale McGlaughlin,
  1971) and evidence of semantic confusion errors
  (were items that mean the same thing are confused
  with each other) in STM (Shulman, 1970, 1972).
• Opposing Evidence - as you will see in the
  discussion of levels of processing, different
  types of processing can occur in what is assumed
  to be STM (Craik Lockhart, 1972)
• 3. The modal model assumes three separate storage
  units
• Opposing Evidence - where does SM end, STM begin
  and LTM begin? There will always be contamination
  of one store with another. Since information has
  to travel from STM to LTM and from LTM to STM to
  be retrieved, how do we know if or what
  information is coming from LTM in retrieval?
  (Nairne, 1996).
• 4. Primacy comes from rehearsing information into
  LTM and recency comes from dumping STM
• Opposing Evidence - primacy can occur with no
  rehearsal (Greene, 1986 Neath Crowder, 1996)
• Opposing Evidence - recency can occur even when
  there have been long delays between study and
  test (Greene, 1986 Nairne, Neath, Serra Byun,
  in press, Neath, 1993)

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Encoding

• How information gets into memory
• Can vary depending upon the nature of retrieval
  (if known) encoding and retrieval do not do
  well independently of each other
• Factors that affect encoding
• Attention
• Repetition multiple experiences with the
  item(s)
• Rehearsal
• Maintenance rehearsal simple repetition
• Elaborative rehearsal thinking about the
  meaning of the item and associating the item to
  information already in memory
• Levels of Processing Theory
• Transfer-Appropriate Processing
• Encoding Specificity Hypothesis

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Levels of Processing Theory

• Craik and Lockhart (1972) Hyde and Jenkins
  (1973)
• Memory structure (SM-STM-LTM) not important for
  this theory
• Type of processing is important
• Shallow processing processing features or
  physical characteristics
• Deep processing processing on the basis of
  meaning or associations
• Results
• Deep processing leads to better memory
  performance
• Problems
• Define "deep"
• Only focuses on encoding, not retrieval or the
  interaction of the two

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Transfer-Appropriate Processing

• Considers both encoding and retrieval makes
  this different from Levels of Processing
• Processing leads to better memory performance
  when the processing at retrieval (test) matches
  the processing used during encoding (study)
• Morris, Bransford Franks (1977)
• Study - Deep (sentence fit) vs shallow processing
  (rhyming)
• Test standard recognition or rhyming
  recognition
• Results
• If subjects in the "deep" condition took the
  standard recognition test, they remembered more
  than subjects in the "shallow" condition (taking
  the standard recognition test)
• If subjects in the "shallow" condition took the
  rhyming recognition test, they remembered more
  than subjects in the "deep" condition (taking the
  rhyming recognition test)

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Encoding Specificity Hypothesis

• Recollection of information depends on the
  interaction between properties of the encoding
  information and properties of the retrieval
  information
• Endel Tulving developed ESP
• Thomson and Tulving (1970)
• Study targets were presented alone during study
  or were presented with a weak cue
• Target flower weak cue fruit strong cue
  bloom
• Test target words were presented alone, with a
  weak cue, or with a strong cue (never studied)
• Results
• If a target word was NOT paired with a cue at
  study, it was best remembered when it was paired
  with a strong cue
• If a target word was paired with a weak cue at
  study, it was best remembered when it was paired
  with a weak cue at test.
• Previously, it was thought that strong cues were
  best for improving memory performance. Thomson
  and Tulving showed that performance depended on
  if the weak cue was presented at study if it
  was, then performance was best when the weak cue
  was again paired with the target word

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Context Effects in Memory

• A change in performance when information is
  studied in one context and remembered in a
  different context
• Environmental Context incidental aspects of the
  environment, not necessary for encoding or
  retrieving information
• Semantic Context gives meaning to items (e.g.,
  bank money or river)
• Example research
• Abernathy (1940) classroom change
• Smith (1979) classroom change
• Light and Carter-Sobell (1970)

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Context Dependent Memory Effects

• Memory can be worse when tested in a new or
  different context relative to when context stays
  the same between study and test
• Works for recall memory tests memory is worse
  with a change in context from study
• Does not work for recognition memory tests
  performance is not different with a change in
  context
• Explanations
• In recall, you are recalling/remembering the item
  and all that is associated with it, which
  includes the context
• In recognition, the item (target) is given back
  to you at test so you do not need additional
  information (like context) to help with
  remembering the item
• How can you get context effects in recognition
  with response bias subjects tend to be more
  conservative in their responses with a change in
  context from study to test.

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State Dependent Memory Effects

• Psychological/emotional state or pharmacological
  state (not a US state)
• Application the reason why we don't remember
  our dreams better is because when we are awake,
  we cannot capture the "state" that we were in
  while dreaming (Prince, 1910)
• If you learn something while you are calm and are
  tested in a state of shock (e.g., earthquake)
  then you will have difficulty remembering what
  you have learned (Susokita, 1934)
• Happy and neutral moods best performance if you
  match the moods between study and test (Bartlett
  Santrock, 1979)
• Alcohol, marijuana, nicotine best performance
  if you match the pharmacological state between
  study and test
• Performance is the absolute worst if you study in
  the pharmacological state and test in a sober
  state (cues are different) but not vice versa