PSY 368 Human Memory

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PSY 368 Human Memory

• Brief History and Methodologies
• Of Human Memory Research

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Quiz 1

• Pass out quiz 1 sheets, allow 5 mins for
  completion

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Early Memory Research
Excellent resource Bower (2000)

• Memory Metaphors
• Wax tablet
• Storage cabinet
• Computer
• Approaches to studying memory
• Structuralist focuses the place(s) in which
  memories are stored
• Proceduralist focuses on the processes of
  creating (and re-creating) memories
• Functionalist focuses on the general principles
  of memory (What does memory do? What is it for?)

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Early Memory Research

• Philosophy
• Ancient Greeks
• Question How do people learn about the world?
• Empiricist tradition sensory experience the
  source of what we know.
• Associations memory of sensory event A is
  associated with memory of sensory event B.
  Retrieval of memory A leads to recall of memory
  B.
• 17th to 19th Century (e.g., Locke, Mills,
  Brown)
• How do sensations combine to form more complex
  thoughts?
• Examined questions about what factors influence
  these associations
• Frequency, duration, distinctiveness, interest,
  recency, resemblance

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Early Memory Research

• Philosophy
• Main methods
• Philosophical Discussion
• Introspection learn how memory works from own
  thoughts
• Before late 1800s
• Non-scientific
• Problems no consistency, no testability, not all
  cognition is conscious

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Early Research in Psychology

• Experimental Psychology
• Modern memory research grew from traditions of
  physical sciences - psychophysicists (Weber,
  Fechner)
• Measurement error
• Distributions of data - one observation is not
  enough
• Sampling error - basis of current inferential
  statistics

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Ebbinghaus (1850-1909)

• Influenced by methods from psychophysics
• Mapped out forgetting function - describes
  manner and speed at which information is
  forgotten
• Set model for good memory research
• Describe two or more theories of how memory works
• Design a study that will test different
  predictions made by the different theories
• Collect data to test the hypotheses to see which
  are supported

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Learn this list

• BAF
• KES
• DOB
• KUD
• MAJ
• POS
• LAR
• FUD
• SOJ
• JAL
• GUC
• REB

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Learn this list

• Recall aloud

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Ebbinghaus Experiments

• Learned lists of nonsense syllables (e.g., GEF,
  BAC) to perfect recall
• Wanted items without previous associations
• All items of equal difficulty
• Rather than examining recall used the Method of
  savings after a delay, how long to relearn list?
• Demonstrated memory for direct and remote
  associations

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Forgetting Function
Basic procedure learn lists until perfect
performance, then after various delays relearn
the lists and see how long it took to relearn to
perfect performance
General Results More remembered with shorter
delay (forgetting function
Q ( savings)
Q percent savings ? difference between time
taken to learn first and second list L time
taken to learn first list 85 time taken to say
2 errorless recitations
Can vary with items learned, type of processing,
type of test, etc., but basic function looks same
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Influence of Ebbinghaus

• Defined proper methodology
• Need for experimental control
• e.g., timing, number of learning trials,
  retention interval, recall time
•  Established forgetting function
• Difficulty of learning as function of length of
  list
• Degrees of learning as function of savings
• Forgetting decreases as function of over
  learning
• Widely distributed learning better than packed
  learning (e.g., 1 per hour vs. 1 per min.)

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Post - Ebbinghaus

• Behaviorist traditions strong emphasis on
  learning (eg. Watson, Hull, Skinner )

• Stimulus-Response (S-R) Associations are central

• Learning S-R associations
• Paired associate learning (car green)
  more frequent pairings lead to stronger learning
  (youtube demo)
• Forgetting S-R associations
• Decay fade away due to weakening of connections
  
• Stimulus generalization as S context changes,
  poorer retrieval of associated R
• Interference other associations get in the way

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Modern Memory Research

• Cognitive Psychology

• Influences from Communication theory Computer
  Sciences

• Memory Processes
• Encoding (meaning, distinctiveness)
• Storage (distributed)
• sensory stores
• STM
• LTM
• Retrieval (different types of memory tests)

Information flows from one memory buffer to the
next
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Review of Methodology

• PSY research relies on the scientific method
  (observations)
• Experiments
• Correlational studies
• Case study designs

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Experiments

• Most common method for memory research
• Allow determination of cause and effect
• Independent variable - manipulated (cause)
• Dependent variable - measured (effect)
• Control variable held constant
• High internal validity, lower external validity

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Correlational Studies

• Look for relationships between measured variables
• No cause and effect - can only see if variables
  are related

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Case Study Designs

• First memory studies done (e.g., Ebbinghaus)
• Lots of measurements from one or a few subjects
• Good control of extraneous variables
• Observe general memory phenomena that are similar
  across subjects
• Current studies - brain injury patients (H.M.)

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Methods exercise

• (1) For the following research questions, think
  about how you might design an experiment to
  answer the question. Try to determine what your
  independent and dependent variables would be.
  What sort of experimental control do you think
  would be important?
• Do people prefer the taste of Coke, Diet Coke, or
  Coke Zero?
• Do electrical stimulation belts (Wear it, watch
  TV, and watch the pounds disappear.) attribute
  to weight loss?
• Does smoking cause lung cancer?
• Are campaign advertisements more effective with
  negative or positive messages?

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Methods Homework

• Due in class on Wednesday Feb. 1