1. Working memory research Group member : 唐牧辰 武天翊 侯晓林 赵诣 赵阳

2. Alan Baddeley and Graham Hitch proposed a Model of Working Memory in 1974, in an attempt to describe a more accurate model of short-term memory. BACKGROUND

3. The central executive is a flexible system responsible for the control and regulation of cognitive processes. It has the following functions: binding information from a number of sources into coherent episodes coordination of the slave systems shifting between tasks or retrieval strategies selective attention and inhibition Central Executive Phonologic al Loop Visual- spatial Sketchpad Episodic Buffer BACKGROUND

4. The phonological loop (or "articulatory loop") as a whole deals with sound or phonological information. It consists of two parts: a short-term phonological store with auditory memory traces that are subject to rapid decay. an articulatory rehearsal component that can revive the memory traces. Phonological loop Central Executive Phonological Loop Visual- spatial Sketchpad Episodic Buffer BACKGROUND

5. Visual-spatial Sketchpad The visual spatial sketchpad is assumed to hold information about what we see. It is used in the temporary storage and manipulation of spatial and visual information, such as remembering shapes and colors, or the location or speed of objects in space. Central Executive Phonologic al Loop Visual- spatial Sketchpad Episodic Buffer BACKGROUND

6. Personal Factors Gender Occupations Age Education Held Factors Central Executive/Episodic Buffer Working memory capacity Inner logical relationship among materials 1 st Experiment Phonological loop/Visual-spatial Sketchpad Information reception channel ( visual / phonological ) 2 nd Experiment Factors may Influence Memory

7. Temperature controlling Space controlling Loudness controlling 25~30 ℃ 40~70 Indoor No Review ! Testing circumstance control

8. Response variables: Memory level (quantity of right numbers remembered) Testing factors: Scale: size of materials (series of integer numbers) Logicality: logicality of materials Time: time span on memorizing materials Testing materials: Number sequence (has covert inner logicality) 1 st Experiment

9. Logicality low: without logicality (logicality unknown), high: without logicality (logicality known) Memory scale Low: 3*6 (divide 18 numbers into three groups with 6 numbers each) high: 2*9 (divide 18 numbers into two groups with 9 numbers each) Experiment time low: morning, med: afternoon, high: night Variables determination

10. Sample collecting time: morning (9:00~11:00), afternoon(14:00~16:00), night(19 ： 00~21 ： 00) Exactly two hours after remembering. Testing methodology Divide the number sequence factitiously Using Access to collect the data Data collection

11. Two and Three level mixed experimental design Number of experiment subjects chosen? Four How to eliminate the noise caused by variability of experiment subjects? Focusing on college students, apply all the runs for every subject. How to quantize memory effects? correct answer in correct position How to eliminate the noise caused by the testing order? Choosing randomized test order Experiment design

12. Design matrix runscalelogicalityXL XQX 1 1LOW 21 1LOW 3 1MED 41 1MED 5 1 MED 611 MED 7 1 HIGH 811 HIGH 91 1 LOW 10111 LOW 111 1 MED 12111 MED 131111MED 1411111MED 151111HIGH 1611111HIGH X stands for the factor “Time” Experiment design

13. 13DOE Scale: -1 stands for low scale (divide 18 numbers into 3 groups), 1 stands for high scale (divide 18 numbers into 2 groups) Time :-1 stands for morning, 0 stands for afternoon, 1 stands for night Logical: -1 means the quizzee doesn’t know the inner logicality of the 18 serials number, 1 means the quizzee get the inner logicality of the numbers. Experiment design Design matrix (cont’d)

14. 14DOE Main effects and the interaction effects Data analysis

15. 15DOE ANOVA The factor “Time” is not significant, so we reduce the design into a two factors full factorial design: Data analysis

16. 16DOE Estimation of the coefficients and ANOVA: Both the two factors and the interaction of them are significant. R-Sq = 75.15% means the model explain 75.15% of the variation, because it is an experiment about human factor, high enough. Data analysis

17. 17DOE Residual We cannot obtain any unique pattern on the residual versus fitted value and the residual versus observation order. Data analysis

18. 18DOE Residual Data analysis

19. 19DOE Residual versus factors The range and the variation of the residuals when the logical factor is at different levels have distinct difference, this can be explained that not all of the persons being tested cannot make good use of the inner logic of the number sequence when he is trying to remember them. Data analysis

20. For short time (exactly two hours later) number sequence memory, the memory index is independent of the “Time” factor. Short time number sequence memory index has great relationship with the scale factor. Short time number sequence memory index has significant relationship with the logicality factor. Short time number sequence memory index has significant relationship with the integration factor of scale and logicality. Conclusion: 20DOE

21. Experiment Design Experiment Material A sequence of two simple shapes Consider the capacity of working memory is approximately between 6 and 10 for most people. And in order to amplify the experiment result, we choose upper-bound. Reception Channel Demonstrate the image on the PPT slides Audio description of the same sequence Combine the visual & audio ways Data Recording Excel files written by Visual Basic micros inside slides 2 st Experiment

22. Subject1Subject2Subject 3 Replication 11-2-33-1-22-3-1 Replication 22-1-31-3-23-2-1 Replication 33-1-22-3-11-2-3 3 specimen 3 treatments (shape/sound/shape & sound) 3 replications 3 specimen 3 treatments (shape/sound/shape & sound) 3 replications To eliminate the block factor of test order as possible, we apply the test as the following sequence Experiment design

23. Data Analysis 23DOE The box plot: the mean responses of the three treatments are different from each other at a significant level.

24. Data Analysis 24DOE One-way ANOVA: P value is smaller than the significant 0.05, which shows that the factor is significant. And the comparison of the mean under different treatments (Tukey )

25. Data Analysis 25DOE One-way ANOVA: However S = 2.768 R-Sq = 23.58% R-Sq （调整） = 18.95% This indicates that our model is weak in explaining the data, only 23.58% of the total variation.

26. Data Analysis 26DOE P value is too small and the residual variance is normally distributed.

27. Data Analysis 27DOE The residual variance displays different distribution in Acceptance Format (0: shape 1:sound 2:shape&sound) The essential reason is that the individual difference and individual preference! Thus we should do ANOVA for every single subject

28. Data Analysis 28DOE Target 1: ANOVA The response is significant thus the image memory is the fittest for the first participant

29. Data Analysis 29DOE Target 2: ANOVA The response is not significant thus we can conclude no optimal memory approach for the second participant

30. Data Analysis 30DOE Target 3: ANOVA The response is significant thus the optimal memory approach for the third participant is shape and shape & sound. R-Sq value is a bit small this indicates that the interpretability is not strong. However, considering the ergonomics, the result is within the acceptance.

31. Data Analysis 31DOE The residual plot of target 3 More replications is needed to eliminate the potential noise!

32. The memory effects varies a lot highly depending on the personal factors. More replications is needed to precisely estimate the personal preference on working memory.

33. Thanks Q&A