human cognitive architecture and its implications for the design of instruction: introduction to...
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Human cognitive architecture and its implications for the design of instruction: Introduction to cognitive load theory
Slava Kayuga
Constructing mental representations of a situation or task
Long-Term Memory Knowledge base
Working Memory
Sensory Memory: Incoming information
Working memory (WM)
Information enters WM once it has been selected by allocating attention to it
We have limited attention because of limitations of WM
Corresponds to consciousness or awareness: we are conscious of everything that is in WM
Repeat a telephone number
12 + 13 = ?
83468437 + 93849045 = ?
Working Memory
Taking notes – extension of WM
What have you been doing just before this?
Early models of memory referred to STM; it
is still commonly used today
STM was thought of in terms of only storing information (temporarily remembering)
Baddeley and Hitch (1974): we not only store information for short periods of time but also process information - hence WM
Short-term or working memory?
WM capacity
Miller (1956) demonstrated that we have a short-term memory span of 7 ± 2 units of information – storage capacity
Reconsideration of WM capacity when processing is involved (Cowan, 2001)
In terms of processing information, 4 is a more likely number than 7
Suppose 5 days after the day before yesterday is Friday. What day of the week is tomorrow?
WM processing capacity
WM duration
Brown (1958); Peterson & Peterson (1959):
When people are distracted from rehearsing, information is lost rapidly (e.g., after 18 sec – everything was forgotten)
Allocates resources to other systems- governs what enters WM
Director of cognitive work- selects strategies
Not a store or processor
Executive Control SystemControls the Operations of
Working Memory
Phonological LoopAuditory Rehearsal
WM StructureBaddeley 1986, 2001
Visual-spatial Sketch PadVisual Rehearsal
Processes visual images Spatial processing
Holds acoustic or speech-based information
Auditory rehearsal of verbal information
Close your eyes and pick up an object in front of you
How many windows are in your house?
Working Memory
Repeat an unfamiliar foreign word
Long-term memory (LTM)
permanent repository of the lifetime of accumulated information
unconscious component of our memory: we are not conscious of LTM information until it is activated and brought into WM
WM and LTM are two major components of Human cognitive architecture
CIABBCABCBHPAMP
CIA BBC ABC BHP AMP
Role of LTM
Effective WM capacity
Miller (1956): short-term memory span is 7 ± 2 chunks of information
What each chunk consists is dependent on our knowledge stored in LTM
What is in LTM would affect the way we process information in WM
Information-“rich” chunks
Chunking information into meaningful parts has the effect of expanding the capacity of working memory
Examples: a Chinese character; a written English word; newspaper vs textbook
Effective WM capacity
Chess studies
Compared performance of chess masters and weekend players
Question: Do chess masters look ahead more moves? Consider a greater number of
alternative moves?
Answer: verbal protocols showed NO difference between chess masters and weekend players
de Groot (1966)
Investigated: players’ memory of chess boards Tested: master’s vs. weekend player’s memory for real
and random board configurations after brief (5 sec) exposure
Results: masters were superior in reconstructing real game configurations (80-90% correct compared to weekenders’ 30-40%) but NOT random configurations
Conclusion: Superiority was due to greater amount of real-game chunks in master’s LTM
Chess studiesde Groot (1966); Chase & Simon (1973)
Grand masters have extensive and better organized LTM knowledge base
50-100 thousand configurations, at least 10 years of experience
This study radically changed our view on the role of LTM in human cognition
LTM is not just for memorizing things, but is the most critical component of our cognition (including learning), the source of our intellectual strength
Role of LTM
Grand masters read the chess board the same way you read words in a text
Similar mechanisms for all high-level cognitive skills (e.g., text comprehension)
LTM - not a passive store of information; it is actively used in most of cognitive processes and is central to perception, learning, problem solving
LTM in human cognition
“Organized structures that capture knowledge and expectations of some aspect of the world” (Bartlett, 1932)
Organized knowledge structures that represent generic concepts and categorize information according to the way in which we use it
Schemas (schemata)
table toastchair butterknife jamfork clothspoon juicecup bowlplate tea
What is this list about?
Schemas
Examples:
a tree schemaa face schema
reading a page of prose: schemas for letters, words, phrases, sentence structures
Restaurant script (procedural schema)
Schema theory is the most commonly used framework for understanding LTM
Memory is actively constructed using schemas
Pre-existing schemas determine what incoming material is relevant Relevant material processed Irrelevant material discarded
Schemas as major building blocks of cognition
Schema automation
Schema automation is achieved by practicing skills until they do not require consciously controlled and effortful processing.
When basic mental operations occur automatically, resources are available for more sophisticated cognitive operations (e.g., reading, math operations, etc.)
Automation
Explains why individuals can conduct difficult tasks simultaneously conduct several tasks read for meaning rather than focus on
the individual letters and words be accomplished performers (e.g.,
musicians) Automation is slow to develop and
requires significant practice
Schemas
Schemas affect not only what we memorize, but how we think, reason, solve problems
Intelligence – in number and complexity of acquired schemas
Nature of expertise
Expert characteristics: Domain-specific knowledge
Experts have a large store of domain-specific schemas for problem solving in the domain
Automated schemas reduce WM demands and allow higher order functions (monitoring, evaluating etc.)
Experts deal with problems at a deeper level: categorize according to deep structures (principles) rather than surface structures
Expert characteristics: Treatment of problem
Task: categorize the following into 3 groups
Soldiers, 1492, discovery, kings & queens, 1914, revolution, sailors, war, 1789.
Surface structure grouping: 1492, 1914, 1789 Deep structure grouping: 1789, Kings and Queens, revolution (French Revolution)
Physics experts classified problems according to the laws of physics rather than surface structures (e.g. Chi, Glaser & Farr, 1988)
Implications for improving problem solving Acquisition of extensive domain-specific
knowledge (schemas) is essential: the only way to be good in problem solving broken car: we call a mechanic (an expert), not
a general “problem solver” You can become expert problem solver in a
specific area, not in every area Studying expert solutions
emphasising higher-order skills, categorization of problems
Analysis of the task domain to identify core schemas:
After 6 passengers had left the bus, 9 passengers remained. How many passengers were on the bus initially? (Change Schema)
Peter's book contains 50 pages. Peter read 15 pages in the morning. In the afternoon, he read the remaining pages and finished the book. How many pages did Peter read in the afternoon? (Group Schema) etc.
Arithmetic word problems(Marshall, 1995)
Go Solve Word ProblemsTom Snyder Productions
Do not overload WM! If material is difficult to learn, learner WM is likely to be overloaded
Manage information-processing “bottleneck” by chunking information into meaningful groups based on available knowledge
Help students to link new information with prior knowledge
Instructional implications
Enhance acquisition and automation of knowledge in LTM - a major goal
Use dual modality (visual and auditory)
Minimise interference /distractions
Provide adequate time to enable processing
Instruction that requires many inferences (things are not stated explicitly) overloads WM
Instructional implications
Instructional theory that takes into account limitations of learner working memory
Cognitive load (working memory load): working memory capacity required by a particular cognitive task
Cognitive load depends on the level of interactivity between elements of information
Cognitive Load Theory
Sweller 1999; Sweller, Ayres & Kalyuga, 2011
List of variables:a, x, b
Equation: ax=b
Names of electricalsymbols and what they represent
Operation of an electrical circuit
Low High
Element interactivity
Learning vocabulary of a foreign language
Learning grammar
Objective measures Task and performance Secondary task Psychophysiological
Subjective measures Rating scales
Measurement of Cognitive Load
Objective measures
Secondary task
Rapid RT Slow RT
Cognitive resources to simple primary task
Cognitive resources to complex primary task
Fixed cognitive capacity Fixed cognitive capacity
Resources to secondary task
Resources to secondary task
very, very low mental
effort
very, very high mental
effort
neither low nor high
mental effort
In solving or studying the preceding problem I invested:
Subjective measures Rating scales
Subjective measures: Rating scales (NASA-
TLX)
Useful, productive load (intrinsic load) – relevant to achieving learning goals
determined by the degree of element interactivity depends on specific instructional goals and prior
knowledge of the learner (chunking!)Wasteful, unproductive load (extraneous load) - irrelevant to learning, imposed by the manner in which information is presented to learners and the learning activities required of them
dependent on the design of instruction
Intrinsic + Extraneous =Total cognitive load
Types of cognitive load
Efficient learningManaging intrinsic (productive) load
Reducing extraneous (wasteful) cognitive load
General rule: Do not do anything that gets in the way of learning!
If intrinsic load is low (simple tasks), there could be no need to reduce extraneous load
References
Sweller, J., van Merriënboer, J. J. G., & Paas, F. G. W. C. (1998). Cognitive architecture and instructional design. Educational Psychology Review, 10, 251-296.
Van Merriënboer, J. J. G., & Sweller, J. (2005). Cognitive load theory and complex learning: Recent developments and future directions. Educational Psychology Review, 17, 147-177.