SHORT-TERM MEMORY SCANNING AS A FUNCTION OF STRESS-

RESISTANCE RESOURCES

Maria S. KapitsaIrina V. BlinnikovaAnna B. Leonova

Moscow State Lomonosov University

Introduction

The effects of emotional states on characteristics of cognitive functioning were frequently investigated in psychological and psychophysiological studies (Martin, Clore, 2001).

At the beginning these effects were considered to be disorganizing (Easterbrook, 1959). Later certain specific effects of emotions were described for different modes of information processing and changing cognitive strategies.

Introduction

It was shown that emotional states exerted effects on working memory, and that the direction of these effects depends on whether pleasant or unpleasant emotions were experienced (Gray, 2001).

Besides it was found that the more distorted processes of short-term memorizing are, the stronger the emotive impact is. They depend on the individual differences, as well (Gray, Braver, Raichle, 2002).

The goals of the current study

To reveal subgroups differing in stress resistance (Leonova, 2001; 2004);

To analyze cognitive performance under emotionally neutral and emotionally tense conditions.

Experiment setup

Participants: 28 subjects: 12 f and 16 m, 17-29 years old

Cognitive task: The Sternberg Item Recognition Task (differentiation of the types of memory search strategies)

Experimental situations:

A. “Ordinary” - routine execution of the Recognition Task with increasing memory load (10 min)

B. “Emotional Stress” – execution of the Recognition Task after negative feedback about the quality of performance (10 min)

Pre-Test Personality

Trait estimation

Test 1 Background

states of subjects

estimation

Cognitive Task

Performance

Emotional Impact

(Negative Feedback)

Cognitive Task

Performance

Test 2 Stress

reactions of subjects (State

changes)

Pre- and post experiment diagnostics

Six subscales to test PERSONALITY TRAITS and emotional disposition:Trait Anxiety Inventory, Trait Anger Inventory, Trait Depression Inventory, Burnout Self-Test, Type A Behavior Questionnaire, Chronic Fatigue Syndrome Test;

Five subscales to test CURRENT EMOTIONAL STATES: State Anxiety Inventory, State Anger Inventory, State Depression Inventory, Well-being Scale, Differential Emotions Scale;

PHYSIOLOGICAL INDICATORS: heart rate, mode and amplitude of RR interval mode, performance of the main spectral components of the heart rate, parameters of sympathetic and parasympathetic links and the integral index of vegetative regulation

Subjects

Higher stress

resistance (17

subjects)

Lower stress

resistance (11 subjects)

The analysis of personality traits and shifts in psychological and physiological indicators allows division of all the subjects into two subgroups considerably contrasting in the levels of stress resistance

Differences between two sub-groups in personality traits

IndicesSubgroup 1 Subgroup 2 Significance

mean mean Z p

Trait Anxiety 48.86 6.33 37.18 3.80 -3.348 < 0.001

Trait Anger 34.00 3.96 30.82 5.33 -1.343 -

Anger-Control 17.29 3.25 12.29 2.44 -3.142 < 0.001

Anger-Expression 16.7 3.99 18.53 4.29 -0.734 -

Trait Depression 23.00 2.94 16.71 2.87 -3.327 < 0.001

T-Euthymia 12.7 1.50 16.06 1.39 -3.509 < 0.001

T-Disthymia 10.7 3.09 7.77 1.79 -2.223 < 0.05

Chronic Fatigue 26.4 8.98 13.18 6.43 -3.155 < 0.001

Type A Behavior 23.57 3.41 18.06 4.70 -2.695 < 0.01

Burnout Emotional exhaustion 26.71 5.82 5.82 5.82 -2.897 < 0.01Depersonalization 12.43 5.86 10.35 3.37 -0.989 -Reduced sense of personal accomplishment

15.43 6.75 15.53 4.45 -0.287 -

Differences between two subgroups in State Scales (first

assessment) Indices Subgroup 1

(11 ss)

Subgroup 2

(17 ss)

Significance

mean mean Z P

Well-being 52.86 5.70 51.59 7.45 -0.96 - State Anxiety 41.00 8.56 35.47 4.95 -1.814 <0.01 State Anger

Feeling Angry Expr. Anger Verbally Expr. Anger Physically

18.43 5.86 6.00 6.57

2.76 1.22 1.29 2.23

15.59 5.24 5.24 5.12

1.73 0.97 0.75 0.33

-3.144 -2.005 -1.701 -2.430

< 0.01 - -

< 0.1 State Depression S-Euthymia S-Disthymia

17.71 14.14 6.86

3.50 2.85 2.34

15.82 14.94 5.77

2.98 1.98 2.02

-1.285 -0.388 -1.591

- - -

Differential Emotion Scale: Positive emotions Negative emotions Anxiety-Depression experience

24.86 18.71 19.86

3.98 7.61 8.36

25.47 13.53 12.82

5.27 2.60 4.99

-0.575 -2.088 -1.990

-

< 0.05 < 0.05

Differences between two subgroups

in State Scales (second assessment)Indices Subgroup 1

(11 ss)

Subgroup 2

(17 ss)

Significance

mean mean Z P

Well-being 46.43 9.14 46.29 7.46 -0.095 - State Anxiety 44.00 6.48 40.41 6.76 -1.345 - State Anger

Feeling Angry Expr. Anger Verbally Expr. Anger Physically

19.29 7.00 5.86

6.43

3.73 1.41 1.21 2.94

16.65 5.94 5.53

5.18

2.91 1.60 1.33

0.39

-2.525 -1.908 -1.086

-1.388

< 0.05 < 0.1

- -

State Depression S-Euthymia S-Disthymia

18.86 13.29 7.14

4.41 3.82 1.95

17.41 13.71 6.12

2.98 2.26 1.45

-0.575 -0.224 -1.223

- - -

Differential Emotion Scale: Positive emotions Negative emotions Anxiety-Depression experience

24.00 18.57 19.43

5.60 7.48 6.45

23.06 13.82 12.59

4.52 3.01 4.45

-0.415 -2.526 -2.269

-

< 0.05 < 0.05

АA

H

N = 31000 ms

1000 ms

200 + 500 ms

Parameters of presentation

Negative Feedback

Subjects were told that their results were considerably worse than standard either in the number of mistakes or in the reaction speed;

Subjects were asked to carry out the second series of the test (in a simplified version) to “reestablish credit” and to achieve higher score.

State Anxiety

30

32

34

36

38

40

42

44

46

1 Ass 2 Ass

subgroup 1 subgroup 2

State Anger

10

12

14

16

18

20

22

24

1 Ass 2 Ass

subgroup 1 subgroup 2

State Depression

10

12

14

16

18

20

22

24

1 Ass 2 Ass

subgroup 1 subgroup 2

Positive emotions

20

22

24

26

28

30

1 Ass 2 Ass

subgroup 1 subgroup 2

Negative emotions

10

12

14

16

18

20

1 Ass 2 Ass

subgroup 1 subgroup 2

Cognitive task

Serial SearchParallel Search

Serial Search Self-Terminating

Serial Search Exhaustive

Sternberg Item Recognition Test

Presentation of a list of 1-7 items (e.g., K, E, B, A, M, J, C);

Presentation of a test item (e.g., P or E);

Subject to say whether or not the test item was on the list;

ET = 200 ms ISI = 500 ms Delay = 1000 ms

Main Results

200

400

600

800

1000

1200

3 4 5 6 7 8 9

RT "YES" RT "NO"

200

400

600

800

1000

1200

3 4 5 6 7 8 9

RT "YES" RT "NO"

200

400

600

800

1000

1200

3 4 5 6 7 8 9

200

400

600

800

1000

1200

3 4 5 6 7 8 9

1. Higher stress-resistant group

2. Lower stress-resistant group

“Mixed Strategy”

“Self-Terminated Search”“Exhaustive Search”

!!!

“Self-Terminated Search”

A.

A.

B.

B.

Conclusions

The high stress resistance group used strategy of an exhaustive memory search which upon an emotional impact switched to the strategy of a self-terminating search increasing the task execution time;

The low stress resistance group demonstrated an opposite trend: the group used the strategy of self-terminating search which upon an emotional impact switched to a mixed strategy demonstrating disorganization of the cognitive functions

Thank you for your attention!