IST

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Canadian and Italian groups ... Level 3: Imitate experimenter who dropped 2 objects in a canister and 1 object in the other ... Level 3: Three objects, seven cups.

Working Memory and its Impact on Cognitive Development in Very Young Children Sergio Morra1, I. Ercan Alp2, Sabrina Panesi1, Paola Viterbori1 Università di Genova 2 Boğazici Üniversitesi (İstanbul)

1

EWOMS-7 (7th European Working Memory Symposium) Edinburgh, September 2-4, 2014

WM demand of early cognitive achievements Secondary circular reaction (Case, 1985) • Pushing repeatedly a mobile object: ψ-arm-movement φ-expected-event 2 sensory-motor schemes

WM demand of early cognitive achievements Object permanence (Pascual-Leone & Johnson, 1991) • Retrieving toy from behind screen B (avoiding A-not-B error): ψ-search φ-screen-B φ-toy-in-hand φ-empty-hand 4 sensory-motor schemes

M-capacity growth for sensory-motor schemes (Pascual-Leone & Johnson, 1991) capacity

typical age (months)

corresponding Piagetian substage

0 1 2 3 4 5 6 7

0-1 1-4 4-8 8-12 12-18 18-26 26-34 34-

Perceptual activity; Exercise of reflexes Coordination of reflexes; Primary circular reactions Secondary circular reactions Means-ends coordination Tertiary circular reactions; Active discovery of means Invention of means; Early representation Explosion of the symbolic function Pre-operational, intuitive thinking

For «translations» between Pascual-Leone’s and Case’s theories, see Pascual-Leone & Johnson (2005)

Measuring very young children’s working memory Imitation Sorting Task – IST (Alp, 1994)

Task: The experimenter drops a set of objects in two canisters; then takes them out and hands them to the child, who is asked to reproduce the sorting. Level 1: Only one object, dropped into one canister. Levels 2-8: Sets of 2 to 8 objects, dropped into two canisters: 1+1, 2+1, 2+2; 3+2; ...... 4+4. Score: The number of objects at the largest set correctly sorted (highest level passed).

IST Performance by Age 7 6

IST score

5 4 3 2 1 0 12-17 mo

Error bars = s.d. of the Canadian and Italian groups

18-23 mo

24-29 mo

Age group

30-36 mo

36-42 mo

Canada

n = 52

Italy

n = 180

Turkey

n = 88

IST Performance by Age 7 6

IST score

5 4 Canada Italy

3

Turkey CDN 1-week

2

Test-retest correlations:

TR 3-weeks

1

(Canada 1 week, Turkey 3 weeks)

Canada r=.80 (.66 age part.out) Turkey r=.87 (.76 age part.out)

0 12-17 mo

18-23 mo

24-29 mo

Age group

30-36 mo

36-42 mo

IST Performance by Age .

7 6

IST score

5 4 Canada Italy

3

Turkey CDN 1-week

2

TR 3-weeks CDN 6-months

Test-retest correlations:

1

TR 9-months

(Canada 6 months, Turkey 9 months)

Canada r=.75 (.55 age part.out) Turkey r=.73 (.57 age part.out)

0 12-17 mo

18-23 mo

24-29 mo

Age group

30-36 mo

36-42 mo

Validity of IST as a Working Memory task (Alp, 1994, 1996) • Performance on IST remains the same when re-tested within 2 weeks, but improves when followed up 6 months later in the age range from 12 to 36 months. • Performance improves about one unit every six months in that age range. • The transition in the data around 19 months (when sorting into two canisters begins) is consistent with categorization observed in free play context (Gopnik & Meltzoff, 1987; Riccuiti, 1965; Sugarman, 1982).

• No sex differences.

Task Analysis for the IST • Level 1: Imitating the experimenter who dropped object in canister • Demonstration: φ-adult-drop φ-canister φ-object φ-obj-in-ca 4 sensory-motor schemes • Performance: φ-obj-in-ca ψ-drop φ-canister φ-object 4 sensory-motor schemes

Task Analysis for the IST • Level 2: Imitate experimenter who dropped 2 objects in different canisters • Demonstration (2nd object): φ-obj1-in-ca φ-adult-turn φ-adult-drop-{ca} φ-object2 φ-obj2-in-ca 5 sensory-motor schemes • Performance (start): φ-obj1-in-ca ψ-turn φ-obj2-in-ca ψ-drop-{ca} φ-object1 5 sensory-motor schemes

Task Analysis for the IST • Level 3: Imitate experimenter who dropped 2 objects in a canister and 1 object in the other • Demonstration: (2nd object) φ-obj1-in-ca φ-adult-drop{ca} φ-object2 φ-obj2-in-ca (interim step) ψ-go-together φ-obj1-in-ca φ-obj2-in-ca → φ-objs1,2-in-ca (3rd object) φ-objs1,2-in-ca φ-adult-turn φ-adult-drop{ca} φ-object3 φ-obj3-in-ca 5 sensory-motor schemes • Performance (start): φ-objs1,2-in-ca ψ-turn φ-obj3-in-ca ψ-drop{ca} φ-object1 5 sensory-motor schemes

Measuring very young children’s working memory - 2 A modified version of the spin-the-pots task • Original task (Hughes & Ensor, 2005): 6 objects hidden in 6 out of 8 very different containers, placed on a tray. The apparatus is covered and rotated, and each time the child is allowed to select a container. Goal: retrieving all 6 objects in as few as possible attempts. • Described as an executive function task. Some significant results, but not consistently. • Perhaps confusing: too much information, both relevant and not.

Measuring very young children’s working memory - 2 Our simplified, span-like version of the spin-the-pots task Level 1: One object, hidden under one of 3 capsized cups in different colours. Level 2: Two objects, five cups. Level 3: Three objects, seven cups. On each trial, the child is allowed to select as many cups as the number of hidden objects, plus one.

Three items per level. Proceed to a higher level only if on at least one item the child found the hidden object(s).

Spin-the-pots, Exp.1 : Effects of rotation and covering • 16 children (age range 18-36 months, mean age = 27.7) • Design: 2x2 (Rotation yes/no X Covering yes/no) i.e., four conditions in two sessions

• 3 levels (1, 2, 3 objects hidden under 3, 5, 7 cups of different colours) 3 items per level • Scoring: 1 point per fully correct item (all n objects found within n attempts); ½ point per nearly-correct item (all n objects found within n+1 trials)

Spin-the-pots, Exp.1 : Effects of rotation and covering 6 5 4

No covering

3

Covering 2

Rotation: F(1,15)=30.75, p