PSY 368 Human Memory Brief History and Methodologies

PSY 368 Human Memory Brief History and Methodologies Of Human Memory Research

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

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? )

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. • 17 th to 19 th 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

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

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

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

Learn this list BAF LAR KES FUD DOB SOJ KUD JAL MAJ GUC POS REB

Learn this list • Recall aloud

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 A B C D

Forgetting Function General Results: More remembered with shorter delay (forgetting function Q (% savings) 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 Q = percent savings Δ = 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

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. )

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

Modern Memory Research • Cognitive Psychology • Influences from Communication theory & Computer Sciences Memory Processes Information ‘flows’ from one memory buffer to the next • Encoding (meaning, distinctiveness) • Storage (distributed) • sensory stores • STM • LTM • Retrieval (different types of memory tests)

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

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

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

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. )

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?

Methods Homework • Due in class on Wednesday Feb. 1