Memory Chapter 7

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MemoryChapter 7
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Memory

• Studying Memory
• An Information-Processing Model
• Two Memory Tracks
• Building Memories
• Encoding Getting Information In
• Storage Retaining Information
• Retrieval Getting Information Out

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Memory

• Forgetting
• Encoding Failure
• Storage Decay
• Retrieval Failure

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Memory

• Memory Construction
• Misinformation and Imagination Effects
• Source Amnesia
• Childrens Eyewitness Recall
• Repressed or Constructed Memories of Abuse?
• Improving Memory

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• Memory is the persistence of learning over time
  through the encoding, storage and retrieval of
  information

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Building a Memory

• To remember any information or experience
  requires
• Encoding getting information into our brain
• Storage retaining the encoded information
• Retrieval getting the information back out of
  memory storage

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An Information-Processing Model

• A model of memory based on a computer (Atkinson
  Shiffrin, 1968)
• Experience is first recorded, for just a moment,
  as a sensory memory
• Information is processed into short-term memory,
  encoded through rehearsal
• Holds a few items briefly
• Information moves to long-term memory for later
  retrieval

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Updates to the I-P Model

• Some memories are formed through unconscious
  processing, without our awareness
• Working memory a view of short-term memory that
  stresses conscious, active processes
• Working memory is not just a storage shelf, but
  an active desktop for linking new and old
  information

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Two-Track Processing Automatic vs. Effortful

• We automatically process vast amounts of everyday
  information
• We remember new and important information through
  effortful processing

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Automatic Processing

• We automatically process information about
• Space
• The definition was at the top of the right page
• Time
• I went to the store before lunch
• Frequency
• This is the third time Ive seen her today!

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Effortful Processing

• Requires close attention and effort
• Memory can be improved through rehearsal, the
  conscious repetition of information
• Rehearsal was the subject of one of many studies
  of memory by Hermann Ebbinghaus

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Ebbinghauss Experiment

• Studied his own learning and forgetting
• Used lists of nonsense syllables
• JIH, BAZ, FUB, YOX, SUJ, DAX, VUM, etc.
• Tested his memory for the list every day.
• The more he practiced out loud on day 1, the less
  time needed to relearn it on day 2

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Effortful Processing

• Spacing effect we remember better if study or
  practice is spread over time
• Cramming is less effective!
• Testing effect repeated quizzing of previously
  studied material also helps

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Serial Position

• Serial position effect We remember the first and
  last items in a list best

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Facts vs. Skills

• H.M. and others with certain traumatic brain
  injuries cannot form new explicit memories
• Cannot learn new facts
• However, they can learn new skills

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Two-Track Memory

• Implicit memory retaining skills or
  conditioning, often without conscious awareness
• Explicit memory memories of facts and personal
  events that can be consciously retrieved

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Two-Track Memory
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Sleep and Memory

• Sleep supports memory consolidation
• During sleep, the hippocampus and cortex display
  rhythmic patterns of activity, as if
  communicating with each other
• The brain may be replaying the days
  experiences as it transfers them to the cortex
  for long-term storage

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Building Memories

• Encoding Getting Information In
• Storage Retaining Information
• Retrieval Getting Information Out

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Encoding Meaning

• We may encode meaning rather than raw information
• When asked to recall text, we often report the
  meaning, or gist, rather than the raw text
• It can be difficult to remember things without a
  meaningful context

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Encoding Images

• We can more easily remember things we can process
  visually as well as meaningfully
• Old Bailey (court in London)--Glen Bailey
• Memorable sentences often evoke powerful imagery,
  or mental pictures
• HOMESthe great lakes
• On Old Olympus' Towering Top, A Finn And German
  Viewed Some Hopsthe cranial nerves
• Olfactory, Optic, Oculomotor, Trochlear,
  Trigeminal, Abducens, Facial, Vestibulocochlear,
  Glossopharyngeal, Vagus, Spinal Accessory,
  Hypoglossal

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Sensory Memory

• Storage is extremely short, especially for visual
  sensory memory
• Study Sperling (1960) flashed nine letters for
  1/20th of a second.
• Sensory memory made the letters momentarily
  available for encoding.

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Short-Term Memory Duration

• Study Peterson (1959) presented 3-letter
  strings and prevented rehearsal
• Result letters 50 gone at 3 seconds, 90 gone
  at 12 seconds.
• Conclusionwithout rehearsaldoesnt last long

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Storage Capacities

• Short-term memory capacity is limited
• The Magical Number Seven, plus or minus two
  (George Miller, 1956)
• 7 digits or 7 chunks of information
• Long-term memory seems to have no limit and can
  endure for a lifetime

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How Does the Brain Store Memory?

• Memory is not stored like books in a library, in
  neat, precise locations.
• Rather, different aspects of a memory are
  assigned to various groups of neurons.
• Thus, to understand how memory works, we must
  study the brain

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Synaptic Changes

• Synapses are the sites where the signal from one
  neuron is received by another
• Experience modifies the brains neural network
  increased activity in a pathway strengthens
  connections between the neurons involved

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Synaptic Changes

• Kandel and Schwartz (1982) classically
  conditioned sea slugs to withdraw their tail when
  squirted with water (with electric shock).
• As the slug learned, serotonin was released into
  certain synapses. These synapses then become more
  sensitive and able to transmit signals more
  effectively.

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Synaptic Changes

• Long-Term Potentiation (LTP) An increase in a
  synapses firing potential. A neural basis for
  learning and memory

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Stress-Related Memories

• Excitement of stress can enhance memories.
• Stress ? hormones ? more available glucose to
  fuel brain activity ? signals brain something
  important has happened
• Do you suppose that is why the pilot at Nellis
  AFB had found it much easier to count air craft
  on the ground when he made high speed-low
  altitude runs over airfields
• in hostile North Vietnam
• than in peaceful England?

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Flashbulb Memories

• Emotion-triggered hormone changes help explain
  flashbulb memories, unusually clear memories of
  an emotionally significant moment or event
• Do you remember exactly where they were on
  September 11, 2001?

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Retrieval Getting Information Out

• Evidence that something has been remembered
• The item can be recalled, on an essay exam
• The item can be recognized, as on a
  multiple-choice test
• Recognition memory is quick and vast
• Relearning the item may be easier than it was the
  first time

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Retrieval Cues

• Memories are linked together in the brain, in a
  storage web of associations.
• These associations can serve as retrieval cues,
  any stimuli (events, feelings, places, etc.)
  linked to a specific memory
• We havent been at the GOP (Garden of Paradise)
  but thinking backAl was at the cash register on
  that occasion.
• Weve not been to Skewers for a couple years-but
  Hani showed us to our table.
• The more retrieval cues youve encoded, the
  better chance of finding a path to retrieve the
  memory

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Context Effects

• Returning to the context where you experienced
  something can prime your memory of it
• Godden and Baddeley (1975) had scuba divers learn
  lists of words on land or underwater, and then
  attempt to recall them in the same or different
  context

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Context Effects

• Sometimes being in a similar context to one
  previously experienced can trigger the eerie
  feeling of déjà vu (Ive seen this before)
• This can happen when the current situation is
  loaded with retrieval cues that remind us of
  earlier, similar experiences
• Where was I went I originally learned this
  particular materialsin class or sitting at home

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Moods and Memories

• Mood-congruent memory we more easily recall
  experiences that are consistent with the current
  (good or bad) mood
• If we are in a good mood, we tend to remember
  good experiences
• Teen ratings of their parents are tightly linked
  to the teens current mood
• If your kid rates you as a parent after waking up
  grouchy, what kind of rating will he make?

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Forgetting

• Jill Price is unable to forget anything.
• Why might this be a problem?

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Seven Sins of Memory (Daniel Schacter, 1999)

• Sins of forgetting and retrieval, problems with
  the way memory works
• Absent-mindedness inattention to detail leads
  to encoding failure
• Transience memory loss as unused information
  fades
• Blocking inability to access stored information

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Seven Sins of Memory (Daniel Schacter, 1999)

• Sins of distortion
• Misattribution confusing the source of
  information
• Suggestibility e.g., asking a leading question
  influences answer and subsequent memory
• Bias belief-colored recollections. Current
  feelings may alter a memory.
• Sin of intrusion
• Persistence unwanted memories (e.g., PTSD)

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Encoding Failure

• We cannot remember what we have not encoded

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Storage Decay

• Forgetting is initially rapid, and then levels
  off
• People who had studied Spanish in high school but
  not after were tested on vocabulary recall
• One explanation may be a gradual fading of the
  memory trace, the physical changes in the brain
  as a memory forms

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Retrieval Failure

• We can sometimes fail to retrieve a memory
  because we dont have enough information to
  access the pathway to it

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Interference

• Interference the blocking of recall as old or
  new learning disrupts the recall of other
  memories
• Learning new passwords may interfere with
  remembering older ones
• Learning an hour before sleep can be good because
  of less interference (but still need rehearsal)

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Forgetting

• Forgetting, the loss of information in between
  sensation and retrieval, can occur at any stages
• Sensory memory
• Short term memory
• Long term memory

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Repressed Memories

• Freud argued that we repress, painful or
  unacceptable memories to minimize anxiety
• He argued that these repressed memories linger,
  and can be retrieved by some later cue or therapy
• Today, many memory researchers think repression
  rarely, if ever, occurs

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Memory Construction

• Every time we replay a memory, we replace the
  original with a slightly modified version
• What implications does this have for everyday
  life?
• My wife and I can have very different memories of
  an event that weve both experience
• And that divergence may grow over time

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Misinformation

• Misinformation effect a memory that has been
  corrupted by misleading information
• Loftus and Palmer (1974) has subjects watch a
  film of a traffic accident.
• How fast were the cars going when they smashed
  into each other?
• or
• How fast were the cars going when they hit each
  other?

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Misinformation

• People who were asked smashed version reported
  higher speeds
• A week later, they were more likely to (falsely)
  recall seeing broken glass

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False Memory and Eyewitness Testimony

• Even hearing a vivid retelling of an event can
  implant false memories
• Sample of 200 convicts later proven innocent by
  DNA testing
• 79 misjudged based on faulty eyewitness
  identification
• Leading questions (Did you hear loud noises)
  can lead to false memories

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Imagination and Memories

• Even imagining fake actions and events can create
  false memories
• College students were asked to imaging specific
  childhood events (like breaking a window with
  their hand). 25 later recalled the event as
  actually having happened.
• Possible cause visualizing something and
  actually perceiving it activate similar brain
  areas

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Source Amnesia

• Source amnesia faulty memory for how, when, or
  where information was learned or imagined
• Sometimes experienced by songwriters and authors,
  who may unintentionally plagiarize something

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Childrens Eyewitness Recall

• How can jurors decide cases in which childrens
  memories of sexual abuse are the only evidence?
• When 3 year-olds were asked to show on a doll
  where a pediatrician had touched them, 55
  pointed to the genitals or anus, even though the
  doctor had not touched them there
• Use non-leading questions soon after the event,
  in language the child can understand

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Repressed or Constructed Memories of Abuse

• Two tragedies concerning adult recollections of
  childhood abuse
• When people dont believe abuse survivors who
  share their secret
• When truly innocent people are falsely accused
• What about clinicians who help people recover
  memories of abuse?

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Guidelines for Thinking about Recovered Memories
of Sexual Abuse

• Sexual abuse happens
• Injustice happens
• Forgetting happens
• Recovered memories are commonplace
• Memories of things happening before age 3 are
  unreliable (Infantile amnesia)
• Memories recovered under hypnosis of under the
  influence of drugs are especially unreliable
• Memories, whether real or false, can be
  emotionally upsetting

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Horror Carves a Memory

• The most common response to a traumatic
  experience is not to banish the experience into
  the unconscious.
• Rather, such experiences are typically etched on
  the mind as vivid, persistent, haunting memories.

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Tips for Improving Memory

• Study repeatedly
• Space study sessions apart
• Spend more time rehearsing or actively thinking
  about the material
• Make the material personally meaningful
• Activate retrieval cues
• Minimize interference
• Sleep more
• Test your knowledge, both to rehearse it and to
  find out what you dont know