1 Why Some Material is Difficult to Learn John Sweller and Paul Chandler, Cognition and Instruction 1994

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Why Some Material is Difficult to Learn

John Sweller and Paul Chandler, Cognition and Instruction 1994.

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Balancing effective learning &

cognitive load

Effective learning Intrinsic

load

Extraneous load

Effective learning

Intrinsicload

Extraneous load

Schema Acquisition

and Automation

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Balancing effective learning &

cognitive load


load

Extraneous load


loadExtraneous load

Schema Acquisition

and Automation

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Example 1: Abstraction of one learner’s cognitive load processing

Learner1Start State

Schema AutomationLow element interactivity

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Learner1Start State

Practice …

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Learner1End State

Automated Schema

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Learner1End State

Automated Schema

Element interactivity irrelevant

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Learner2Start State

Schema AutomationHigh element interactivity

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Schema Automation

Low element interactivity

Learner2Intermediate State

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Schema Automation

Low element interactivity

Practice…

Learner2Intermediate State

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Learner2End State

Automated Schema

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Learners’ cognitive loads have different start states

Learner1Start State

Learner2Start State

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Learners’ cognitive loads have same end states

Learner1End State

Learner2End State

Automated Schema

Automated Schema

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Large cognitive load

• Means “multiple interacting elements”

Difficulty = number of elements + degree of interactivity

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Large cognitive load

• Means “multiple interacting elements”

Difficulty = number of elements + degree of interactivity

• “…the task is difficult not because it is difficult to assimilate each element but because a huge number of elements must be assimilated.”

(p. 188, Sweller & Chandler)

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“multiple interacting elements” (??)• Elements Schema • No useful distinction

– An element is a schema is an element is a schema ….

• In particular,– Elements Lower order schema

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“multiple interacting elements” (??)• Elements Schema • No useful distinction

– An element is a schema is an element is a schema ….

• In particular,– Elements Lower order schema

• Recursive definition (!)– When does the madness end?

• Base case?– When an automated process is reached

• Stack overflow?– Working memory exhausted

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Split-Attention Effect

• Requires learner to split their attention among and mentally integrate multiple sources of information

• Causes learner to associate redundant elements (text) with essential diagram and increases element interactivity

Redundancy Effect

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• Segments of information unintelligible until physically or mentally integrated


• Segments of information that can be understood in isolation

Redundancy Effect

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• Segments of information unintelligible until physically or mentally integrated

• Extraneous cognitive load matters


• Segments of information that can be understood in isolation

• Extraneous cognitive load matters

Redundancy Effect

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Experiment One of Four

• Compared CAD/CAM systems conventional-manual-plus-computer group with modified-manual-only– Twenty first-year trade apprentices (gender not specified)– Small test booklet and hardware & software for practical tests

• Demonstrated split-attention effect using materials with high degree of interaction between individual elements– “modified-manual-only” operationalized by”…wherever the

conventional manual required learners to look at the screen or keyboard, the modified-manual had illustrations integrated with the text.” (p. 196)

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Experiment Two of Four

• Now, three groups: CAD/CAM systems conventional-manual-plus-computer group, modified-manual-only group, and modified manual interacting with computer– Thirty year 7 (?) high school students– Small test booklet+ equipment and hardware & software for

practical tests• On low element interactive tasks, there was no difference

between groups (as hypothesized). Significant differences existed between modified-manual-only group and other two groups demonstrate redundancy effect– Caution: Data questionable

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Experiment Three of Four

• Same three groups from Experiment Two but with different presentation formats– Same (?) thirty year 7 (?) high school students– Similar small test booklet+ equipment and hardware &

software for practical tests

• As expected, no difference between groups performing low element interactive tasks– Word processing tasks could be learned in isolation and

thus any extraneous cognitive load imposed by computer not an important factor

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Experiment Four of Four

• Same three groups from previous experiment – Thirty first-year trade apprentices

• No prior experience testing an electrical appliance– Similar small test booklet+ equipment and hardware & software

for practical tests• Both split-attention and redundancy effects demonstrated:

– Modified-manual reduced extraneous cognitive load for high element interactive tasks

– On low element interactive tasks, no difference in performance occurred (supporting redundancy effect (?how?))

– Results seemed to generalize to non-computer-based tasks

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Split-attention effect

Redundancy effect

Intrinsic load

Extraneous load

High element interactive tasks

Experiment One

Experiment Four

high Negative effects

Low element interactive tasks

Experiment TwoExperiment Three

low No effect

Documents

1 Why Some Material is Difficult to Learn John Sweller and Paul Chandler, Cognition and Instruction 1994