Experimental Psychology PSY 433

1. Experimental PsychologyPSY 433 Chapter 10 Memory

2. What is Plagiarism? • http://www.indiana.edu/~wts/pamphlets/plagiarism.shtml#plagiarized

3. Samples from Past Student Papers • The participants will report to a specified lab room in building 5. Participants will be greeted and asked to quietly take a seat at a computer station. • Subjects will report to a specified lab room in building 5. Upon entering the lab subjects will be greeted and asked to quietly take a seat. • This is Unacceptable

4. Another Unacceptable Example • Using a bivalent within-subjects design, we will be measuring the affect… • Using a bivalent within-subjects design, we will measure the participant’s correct responses. • We will be using a bivalent within-subjects design measuring both the affects of the sex… • Using a bivalent design, the correct responses of the participants will be measured…

5. One More Unacceptable Example • Data was analyzed using SPSS a statistics software program produced by IBM. A 0.05 significance level was used. • Information was collected from the participants’ responses and was evaluated at the .05 level of significance using SPSS known as a statistical software developed by IBM. • One student clearly used a group member’s paper as a template for writing the Results.

6. Ebbinghaus’s Techniques • Nonsense syllables – controls for prior experience and knowledge of meanings. • Trials to criterion – keep practicing until the words are perfectly learned, count trials needed. • Savings score – percentage of trials saved in relearning a list, relative to original trials needed. • Example: 10 – 5 / 10 x 100% = 50% • 10 original learning (OL), 5 relearning (RL)

7. Varieties of Memory • Short-term vs long-term memory • Atkinson & Shiffrin’s 3-stage model • Procedural vs declarative (semantic) • Memory for doing things vs knowledge of facts • Explicit (episodic & semantic) vs implicit memory • Tulving’s idea that consciousness makes a difference. • Implicit includes procedural memory but also priming

8. Name the Seven Dwarfs

9. Is it easier with the picture?

10. A Recognition Task • Which of the following are names of the Seven Dwarfs? Goofy Bashful Sleepy Meanie Smarty Doc Scaredy Happy Dopey Angry Grumpy Sneezy Wheezy Crazy

11. Dependent Variables • Recall -- % or proportion remembered • Serial recall • Free recall • Paired-associates recall • Recognition -- % or proportion remembered • Yes/No • Forced choice (multiple choice) • Primed recognition– e.g., stem completion

12. Independent Variables • The kind of material to be remembered: • Letters, digits, nonsense syllables, words, phrases, sentences, paragraphs, passages of prose. • Retention interval – how fast does forgetting occur? • Modality of presentation – visual vs verbal. • Encoding strategies • Type of test – recall vs recognition.

13. Control Variables • Amount and type of material presented. • Concreteness vs abstractness of words. • Rate of presentation. • Modality of presentation – eyes, ears. • Each of these could also be an IV – but do not vary everything in the same experiment. • Whatever is varied, the other aspects should be controlled.

14. Scale Attenuation Effects • Memory experiments are especially sensitive to difficulty of the task: • Ceiling effects occur when the task is too easy and everything gets nearly 100% correct. • Floor effects occur when the task is too difficult and few people get any questions correct. • Aim for 80% correct in the control group. • Test your items before manipulating the IV.

15. Scarborough’s Experiment • Used the Brown-Peterson technique to measure short-term memory: • A trigram is followed by distractor task after a certain number of seconds. • Percentage correct is measured • Proactive interference makes the task difficult: • trigrams seen on previous tasks interfere with remembering subsequent trigrams.

16. Scarborough’s Design • Do we remember info better if we see it or hear it – does modality of presentation matter? • IV 1 – Presentation modality: • Visual Only group saw the trigrams • Auditory Only group heard the trigrams read aloud • Both group saw and heard the trigrams. • IV 2 – Retention interval: 0, 3, 6, 9, 12, 18 sec • DV – Proportion correctly recalled.

17. Which condition did better?

18. Scarborough’s Results • Subjects who only saw the trigrams did as well as subjects who both saw and heard the trigrams. • Subjects who only heard the trigrams did worse than those who saw or both saw and heard them. • Seeing produces better retention than hearing.

19. Different Rates of Forgetting? • Decline in retention appears steeper for those who only heard the trigrams. • Does this mean auditory presentation results in faster forgetting? • A ceiling effect complicates this interpretation. • All three modalities are at 100% at 0 sec. • With a higher ceiling, the decline for visual modality might have shown the same slope as for auditory.

20. Weight Loss Example • Two men make a bet about who can lose the most weight. • They weigh themselves on a scale that tops out at 300 lbs. • Both weigh 300 lbs on the scale, although one actually weighs 350 while the other truly weighs 300. • Both lose 100 lbs, so one now weighs 200 while the other weighs 250. Who won the bet?

21. Pilot Studies are Important! • Avoid extremes of performance (high or low) by testing materials on pilot subjects. • Make the task more difficult by increasing the amount of material to be remembered, presenting it faster, testing after a longer time interval, etc. • Make the task easier by decreasing material, slowing down presentation rate, etc.