Memory Mechanisms

1
Memory Mechanisms

• Information from the world enters and flows
  through a number of cognitive processes before
  ending as a response to the world

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Long-Term Memory

• Mobile Conjugate Reinforcement Paradigm
• Operant conditioning
• Procedure
• Nonreinforcement (baseline)

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Long-Term Memory

• Mobile Conjugate Reinforcement Paradigm
• Operant conditioning
• Procedure
• Nonreinforcement (baseline)
• Reinforcement (learning)
• Test (after a delay)

4
Long-Term Memory

• Mobile Conjugate Reinforcement Paradigm
• Operant conditioning
• Procedure
• Nonreinforcement (baseline)
• Reinforcement (learning)
• Test (after a delay)

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Long-Term Memory
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Long-Term Memory Older Infants

• The mobile paradigm only works up to 6 months
• Infant turns over
• Infant tries grabbing the mobile
• Infant longer finds the mobile game interesting

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Long-Term MemoryOlder Infants

• Hartshorn, Aaron, Livolsi, Hille, Rovee-Collier
  (1995) develop a reinforcement paradigm with a
  train and test every 3 months from 6 to 18 months
  of age

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Determinants of Retention Training

• Does more training lead to better retention?
• Ohr, Fagen, Rovee-Collier, Hayne, Linde (1987)
  examined the effect of training on the retention
  of 3-month-olds
• Trained infants for 1, 2, or 3 sessions of 9
  minutes each
• Trained infants for a single session for 6, 9,
  12, or 18 minutes

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Number of Sessions

• After 1 session, remember for 1 day but not 7
• After 2 sessions, remember for 7 days but not 14
• After 3 sessions, remember for 7 days and perhaps
  14, but not 21

10
Training Duration

• After 6 and 9 minutes, did not remember after 7
• After 12 minutes, may exhibit retention after 7
  days, but not 14
• After 18 minutes, remember for 14 days but not 21

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Determinants of Retention Attention

• Adler Rovee-Collier (1994) showed that infants
  remembered s for 7 days, but Ls and Ts for only
  3 days
• Hypothesized this was due to more attention being
  allocated to s because they contain more features

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Determinants of Retention Attention

• Adler et al (1998) examined the effect of
  attention by training infants with a pop-out
  display
• Single among Ls or single L among s
• If retention is affected by attention, then the
  pop-out target should be remembered longer
• Found that with among Ls, s remembered for 9
  days, Ls remembered for 1
• With L among s, Ls remembered for 7 days, s
  remembered for 3 days

Test
Test L
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Long-Term MemoryForgotten or Not

• Are memories truly forgotten or are they simply
  inaccessible?
• Infantile Amnesia
• Provide a reminder at a point in time when the
  memory is supposedly forgotten

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Long-Term MemoryForgotten or Not

• At 3 months, takes 3 days after reminder for
  memory to come back fully
• At 6 months, it takes 8 hours
• At 9 months, it takes 1 hour
• At 12 months, instantaneously

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Long-Term MemoryForgotten or Not

• At 3 months, takes 3 days after reminder for
  memory to come back fully
• At 6 months, it takes 4 hours
• At 9 months, it takes 1 hour
• At 12 months, instantaneously

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Types of Memory

• Declarative (I.e. Episodic Explicit)
• Memory for specific events
• Procedural (I.e. Semantic Implicit)
• Memory for how to do things General knowledge

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Infants LTM

• Memory tapped by the mobile game has been
  hypothesized to be procedural memory
• Infants are remembering how to kick to the
  presented mobile
• If this is the case, then infants, as long as
  they remember, should kick to any mobile

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LTM Specificity

• Examine whether infants remember the specific
  mobile with which they learned
• If so, then memory cannot be procedural
• Rovee-Collier Sullivan (1980) trained 3-mo-olds
  with one mobile and tested them, after different
  delays, with either same or a different mobile

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Rovee-Collier Sullivan (1980)
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Memory Specificity

• Rovee-Collier Sullivan (1980) results indicate
  that very young infants memory is very specific
• Though they remember general information longer
  than specific information
• Not compatible with a procedural memory view
• Hayne, Rovee-Collier, Borza (1991) examined
  infants memory for place information

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Hayne, Rovee-Collier, Borza (1991)
22
Memory Summary

• What seems to develop is the quantitative aspects
  of memory, not the qualitative aspects
• That is, with development, events are remembered
  across longer delays and are retrieved at a
  faster rate

23
Constructive Memory

• Use of knowledge structures and previously
  remembered events to interpret new information,
  thereby affecting how it is remembered
• Eyewitness Testimony
• Witness an event, then asked leading, suggestive
  questions

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Suggestibility of Childrens Memory

• Ceci, Ross, Toglia (1987)
• Presented children with a story about a girl who
  got a stomach-ache after eating eggs at breakfast
• Two conditions Biased and unbiased

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Memory Modification

• Happens in adults eyewitness testimony
• Is this a basic mechanism of memory?
• Infant mobile studies - after training, passively
  expose infants to novel mobile

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Memory Modification

• Memory is not completely accurate and can be
  modified
• Infant childhood memories are not accurate but
  have been constructed
• May be cause of infantile amnesia
• Adler (1997) - Selective Integration

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Types of Memory

• It has been hypothesized that the different
  memory systems develop at different rates
• Based on dissociations on particular tasks
  (priming vs. recognition-recall) in aging and
  amnesiacs
• The memory system (implicit) spared in amnesiacs
  is primitive and functional in early development
• The memory system (explicit) that is impaired in
  amnesiacs is a higher level and functional late
  in the first year

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Types of Memory

• Research with infants has in fact shown the same
  dissociations in infants as are found in normal
  adults
• Thereby disputing that the different systems have
  different developmental trajectories
• Two tests Direct test of memory
  (recognition-recall) and indirect test (priming)
• Recognition-recall is thought to access explicit
  memory priming thought to access implicit memory
• If a variable effects performance on one of the
  tasks but not the other, then have dissociation