Working memory researchWorking memory research

Group member : 唐牧辰 武天翊 侯晓林 赵诣 赵阳

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.

BACKGROUNDBACKGROUND

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

Central Executive

Phonological Loop

Visual-spatial

Sketchpad

Episodic Buffer

BACKGROUNDBACKGROUND

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

BACKGROUNDBACKGROUND

•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

Phonological Loop

Visual-spatial

Sketchpad

Episodic Buffer

BACKGROUNDBACKGROUND

Personal Factors •Gender• Occupations• Age• Education Held Factors

Central Executive/Episodic Buffer • Working memory capacity• Inner logical relationship among materials

1st Experiment

Phonological loop/Visual-spatial Sketchpad• Information reception channel ( visual / phonological )

2nd Experiment

Factors may Influence MemoryFactors may Influence Memory

Temperature controllingTemperature controlling

Space controllingSpace controlling

Loudness controllingLoudness controlling

25~30 ℃ 25~30 ℃

40~7040~70

IndoorIndoor

No Review !

Testing circumstance control Testing circumstance control

Response variables: Memory level (quantity of right numbers remembered)

Testing factors:Scale: size of materials (series of integer numbers)Logicality: logicality of materialsTime: time span on memorizing materials

Testing materials:Number sequence (has covert inner logicality)

1st Experiment1st Experiment

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 timelow: morning, med: afternoon, high: night

Variables determinationVariables determination

Sample collecting time: morning (9:00~11:00), afternoon(14:00~16:00), night(19： 00~21： 00)Exactly two hours after remembering.

Testing methodologyDivide the number sequence factitiouslyUsing Access to collect the data

Data collection Data collection

• 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 Experiment design

Design matrixrun scale logicality XL XL XQ X

1 -1 -1 -1 -1 1 LOW2 1 -1 -1 -1 1 LOW3 -1 -1 -1 -1 1 MED4 1 -1 -1 -1 1 MED5 -1 -1 1 -1 -1 MED6 1 -1 1 -1 -1 MED7 -1 -1 1 -1 -1 HIGH8 1 -1 1 -1 -1 HIGH9 -1 1 -1 1 -1 LOW

10 1 1 -1 1 -1 LOW11 -1 1 -1 1 -1 MED12 1 1 -1 1 -1 MED13 -1 1 1 1 1 MED14 1 1 1 1 1 MED15 -1 1 1 1 1 HIGH16 1 1 1 1 1 HIGH

X stands for the factor “Time”

Experiment design Experiment design

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 Experiment design Design matrix (cont’d)

14DOE

• Main effects and the interaction effects

1-1

16

15

14

13

121-1

10-1

16

15

14

13

12

scal e

平均值

l ogi cal

Ti me

Response 主效应图数据平均值

16

14

12

1- 1

1- 1

16

14

12

10- 1

16

14

12

Ti me

l ogi cal

scal e

-101

Ti me

-11

l ogi cal

-11

scal e

Response 交互作用图拟合平均值

Data analysisData analysis

15DOE

• ANOVA The factor “Time” is not

significant, so we reduce the design into a two factors full factorial design:

Data analysisData analysis

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 analysisData analysis

17DOE

• Residual

• We cannot obtain any unique pattern on the residual versus fitted value and the residual versus observation order.

5. 02. 50. 0-2. 5-5. 0

99. 9

99

90

50

10

1

0. 1

残差

百分比

16. 815. 614. 413. 212. 0

2

0

-2

-4

拟合值

残差

3210-1-2-3

16

12

8

4

0

残差

频率

605550454035302520151051

2

0

-2

-4

观测值顺序

残差

正态概率图 与拟合值

直方图 与顺序

Response 残差图

Data analysisData analysis

18DOE

• Residual

5. 02. 50. 0- 2. 5- 5. 0

99. 9

99

95

90

80706050403020

10

5

1

0. 1

残差2

百分比

均值 0

标准差 1. 246

N 64AD 0. 731

P 值 0. 054

残差2 的概率图正态 - 95% 置信区间

Data analysisData analysis

19DOE

• Residual versus factors

1. 00. 50. 0- 0. 5- 1. 0

3

2

1

0

- 1

- 2

- 3

- 4

scal e

残差

残差与 scal e（响应为 Response）

1. 00. 50. 0- 0. 5- 1. 0

3

2

1

0

- 1

- 2

- 3

- 4

l ogi cal

残差

残差与 l ogi cal（响应为 Response）

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.

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 analysisData analysis

• 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:Conclusion:

20DOE

Experiment Design

Experiment Material• A sequence of two simple shapesConsider 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

2st Experiment2st Experiment

Subject1 Subject2 Subject 3

Replication 1 1-2-3 3-1-2 2-3-1

Replication 2 2-1-3 1-3-2 3-2-1

Replication 3 3-1-2 2-3-1 1-2-3

• 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 Experiment design

Data Analysis Data Analysis

23DOE

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

soundshape&soundshape

10

9

8

7

6

5

4

3

2

1

Acceptance_Format

Response

Response 的箱线图

Data Analysis 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 )

Data Analysis Data Analysis

25DOE

• One-way ANOVA:

However S = 2.768 R-Sq = 23.58% R-Sq （调整） = 18.95% 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.•This indicates that our model is weak in explaining the data, only 23.58% of the total variation.

Data Analysis Data Analysis

26DOE

• P value is too small and the residual variance is normally distributed.

1050- 5- 10

99

95

90

80

70

605040

30

20

10

5

1

存储残差1

百分比

均值 0标准差 2. 687N 36AD 1. 012P 值 0. 010

存储残差1 的概率图正态 - 95% 置信区间

Data Analysis Data Analysis

27DOE

• The residual variance displays different distribution in Acceptance Format (0: shape 1:sound 2:shape&sound)

2. 01. 51. 00. 50. 0

5. 0

2. 5

0. 0

- 2. 5

- 5. 0

- 7. 5

Acceptance Format

残差残差与 Acceptance Format

（响应为 Response）

The essential reason is that the individual difference and individual preference!The essential reason is that the individual difference and individual preference!

•Thus we should do ANOVA for every single subject•Thus we should do ANOVA for every single subject

Data Analysis Data Analysis

28DOE

• Target 1: ANOVA

• The response is significant thus the image memory is the fittest for the first participant

Data Analysis Data Analysis

29DOE

• Target 2: ANOVA

• The response is not significant thus we can conclude no optimal memory approach for the second participant

Data Analysis 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.

Data Analysis Data Analysis

31DOE

The residual plot of target 3

7. 55. 02. 50. 0- 2. 5- 5. 0

99

95

90

80

70

605040

30

20

10

5

1

存储残差3

百分比

均值 4. 934325E- 16标准差 1. 803N 9AD 0. 414P 值 0. 261

存储残差3 的概率图正态 - 95% 置信区间

More replications is needed to eliminate the potential noise!More replications is needed to eliminate the potential noise!

• 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.

Conclusion:Conclusion:

ThanksQ&A