Cognitive load is a term that refers to the load on
working memoryWorking memory is a theoretical construct within cognitive psychology as to the structures and processes used for temporarily storing and manipulating information in short-term memory. Many theories exist both as to the theoretical structure of working memory as well as to the role of specific...
during instruction.
Instruction may be aimed at teaching learners
problem solvingProblem solving is a mental process and is part of the larger problem process that includes problem finding and problem shaping. Consideredthe most complex of all intellectual functions, problem solving has been defined as higher-order cognitive process that requires the modulation and control of...
skills, thinking and reasoning skills (including perception, memory, language, etc.) Many would agree that people learn better when they can build on what they already understand (known as a
schemaA schema , in psychology and cognitive science, is a mental structure that represents some aspect of the world. Schemata were initially introduced into psychology and education through the work of the British psychologist Sir Frederic Bartlett...
), but the more a person has to learn in a shorter amount of time, the more difficult it is to process that information in working memory.
Cognitive load is a term that refers to the load on
working memoryWorking memory is a theoretical construct within cognitive psychology as to the structures and processes used for temporarily storing and manipulating information in short-term memory. Many theories exist both as to the theoretical structure of working memory as well as to the role of specific...
during instruction.
Instruction may be aimed at teaching learners
problem solvingProblem solving is a mental process and is part of the larger problem process that includes problem finding and problem shaping. Consideredthe most complex of all intellectual functions, problem solving has been defined as higher-order cognitive process that requires the modulation and control of...
skills, thinking and reasoning skills (including perception, memory, language, etc.) Many would agree that people learn better when they can build on what they already understand (known as a
schemaA schema , in psychology and cognitive science, is a mental structure that represents some aspect of the world. Schemata were initially introduced into psychology and education through the work of the British psychologist Sir Frederic Bartlett...
), but the more a person has to learn in a shorter amount of time, the more difficult it is to process that information in working memory. Consider the difference between having to study a subject in one's native
languageA language is a system for encoding and decoding information. In its most common use, the term refers to so-called "natural languages" — the forms of communication considered peculiar to humankind. In linguistics the term is extended to refer to the human cognitive facility of creating and using...
versus trying to study a subject in a foreign language. The
cognitive load is much higher in the second instance because the brain must work to translate the language while simultaneously trying to understand the new information.
Another aspect of cognitive load theory involves understanding how many discrete units of information can be retained in short term memory before information loss occurs. An example that seems to be commonly cited of this principle is the use of 7-digit phone numbers, based on the theory that most people can only retain seven "chunks" of information in their short term memory. Refer to
Chunking (psychology)In cognitive psychology and mnemonics, chunking refers to a strategy for making more efficient use of short-term memory by recoding information. More generally, Herbert Simon has used the term chunk to indicate long-term memory structures that can be used as units of perception and meaning, and...
.
Cognitive load theory
"Cognitive load theory has been designed to provide guidelines intended to assist in the presentation of information in a manner that encourages learner activities that optimize intellectual performance" (Sweller, van Merriënboer, and Paas, 1998, p. 251).
SwellerJohn Sweller is an Australian educational psychologist who is best known for formulating an influential theory of cognitive load.He has a Ph.D. from the University of Adelaide's Department of Psychology — his thesis was titled "Effects of initial discrimination training on subsequent shift learning...
's theory employs aspects of
information processingInformation processing is the change of information in any manner detectable by an observer. As such, it is a process which describes everything which happens in the universe, from the falling of a rock to the printing of a text file from a digital computer system...
theory to emphasize the inherent limitations of concurrent
working memoryWorking memory is a theoretical construct within cognitive psychology as to the structures and processes used for temporarily storing and manipulating information in short-term memory. Many theories exist both as to the theoretical structure of working memory as well as to the role of specific...
load on learning during instruction. It makes use of
schemasA schema , in psychology and cognitive science, is a mental structure that represents some aspect of the world. Schemata were initially introduced into psychology and education through the work of the British psychologist Sir Frederic Bartlett...
as the unit of analysis for the design of instructional materials.
The history of cognitive load theory
The history of cognitive load theory can be traced back to the beginning of Cognitive Science and the work of G.A. Miller (1956). Miller was perhaps the first to suggest our working memory capacity was limited in his classic paper . He suggested we are only able to hold seven plus or minus two digits of information in our short term memories. Miller's early work was built upon by many researchers in the ensuing decades. Perhaps most notably by that of Simon and Chase (1973) who also used the term "chunk" to describe how experts use their short term memories. As novices learn, they begin to see patterns in the world around them. These patterns can be combined with other patterns... this chunking of memory components has also been described as
schemaThe word schema comes from the Greek word "σχήμα" , which means shape, or more generally, plan. The plural is "σχήματα"...
construction.
John SwellerJohn Sweller is an Australian educational psychologist who is best known for formulating an influential theory of cognitive load.He has a Ph.D. from the University of Adelaide's Department of Psychology — his thesis was titled "Effects of initial discrimination training on subsequent shift learning...
developed cognitive load theory while studying problem solving . While studying learners as they solved problems, he and his associates found that learners often use a problem solving strategy called
means-ends analysisMeans-Ends Analysis is a technique used in Artificial Intelligence for controlling search in problem solving computer programs.It is also a technique used at least since the 1950s as a creativity tool, most frequently mentioned in engineering books on design methods...
. He suggests problem solving by means-ends analysis requires a relatively large amount of cognitive processing capacity, which may not be devoted to schema construction. Instead of problem solving, Sweller suggests Instructional designers should limit cognitive load by designing instructional materials like worked-examples, or goal-free problems.
In the 1990s, Cognitive load theory was applied in several contexts and the empirical results from these studies led to the demonstration of several learning effects: the completion-problem effect ;
Modality effectMultimedia learning is the common name used to describe the cognitive theory of multimedia learning This theory encompasses several principles of learning with multimedia.-The Modality principle:...
; Split-attention effect ; the
Worked-example effectThe worked-example effect is a learning effect predicted by cognitive load theory . According to Sweller: "The worked example effect is the best known and most widely studied of the cognitive load effects"....
and the expertise reversal effect .
Types of cognitive load
Cognitive load theory has broad implications for
Instructional designInstructional Design is the practice of maximizing the effectiveness, efficiency and appeal of instruction and other learning experiences. The process consists broadly of determining the current state and needs of the learner, defining the end goal of instruction, and creating some "intervention"...
(Sweller, 1999). This theory provides a general framework for instructional designers for it allows them to control the conditions of learning, within an environment, or more generally within most instructional materials. Specifically, it provides empirically-based guidelines that help instructional designers to decrease extraneous cognitive load during learning, and refocus that learner's attention toward germane materials, increasing germane (schema related) cognitive load.
This theory differentiates between three types of cognitive load:
intrinsic cognitive loadIntrinsic cognitive load is the inherent level of difficulty associated with instructional materials.The term "Intrinsic cognitive load" was first described by . According to Chandler and Sweller, all instruction has an inherent difficulty associated with it...
,
germane cognitive loadGermane cognitive load is that load devoted to the processing, construction and automation of schemas.Germane load was first described by Sweller, van Merrienboer and Paas in 1998...
, and
extraneous cognitive loadExtraneous cognitive load is the working memory load experienced by learners as they interact with instructional materials. This is a type of cognitive load that instructional designers do have some ability to control...
Intrinsic cognitive load
The term "Intrinsic cognitive load" was first described by Chandler and Sweller (1991). Accordingly all instruction has an inherent difficulty associated with it (e.g., the calculation of 2 + 2, versus solving a
differential equationA differential equation is a mathematical equation for an unknown function of one or several variables that relates the values of the function itself and its derivatives of various orders...
). This inherent difficulty may not be altered by an instructor. However many schemas may be broken into individual "subschemas" and taught in isolation, to be later brought back together and described as a combined whole .
Extraneous cognitive load
Extraneous cognitive load is generated by the manner in which information is presented to learners and is under the control of instructional designers (Pollock, Chandler & Sweller, 2002). This load can be attributed to the design of the instructional materials.
Sweller provides a wonderful example of extraneous cognitive load in his 2006 book, when he describes two possible ways to describe a square to a student . A square is a visual and should be described using a visual medium. Certainly an instructor can describe a square in a verbal medium, but it takes just a second and far less effort to see what the instructor is talking about when a learner is shown a square, rather than having one described verbally. In this instance, the efficiency of the visual medium is preferred. This is because it does not unduly load the learner with unnecessary information. This unnecessary cognitive load is described as extraneous cognitive load.
Germane cognitive load
Germane load was first described by Sweller, van Merrienboer and Paas in 1998. It is that load devoted to the processing, construction and automation of
schemataA schema , in psychology and cognitive science, is a mental structure that represents some aspect of the world. Schemata were initially introduced into psychology and education through the work of the British psychologist Sir Frederic Bartlett...
. While intrinsic load is generally thought to be immutable, instructional designers can manipulate extraneous and germane load. It is suggested that they limit extraneous load and promote germane load .
Measurement of cognitive load
Paas and van Merriënboer (1993) developed a construct (known as relative condition efficiency) which helps researchers measure perceived mental effort, an index of cognitive load. This construct provides a relatively simple means of comparing instructional conditions. It combines mental effort ratings with performance scores. Group mean z-scores are graphed and may be compared with a one-way ANOVA.
Paas and van Merriënboer (1993) used relative condition efficiency to compare three instructional condition (worked examples, completion problems, and discovery practice). They found learners who studied worked examples were the most efficient, followed by those who used the problem completion strategy. Since this early study many other researchers have used this and other constructs to measure cognitive load as it relates to learning and instruction (Paas, Tuovinen, Tabbers, & Van Gerven, 2003).
The ergonomic approach seeks a quantitative neurophysiological expression of cognitive load which can be measured using common instruments. Fredericks T.K., Choi S.D,. Hart J., Butt S.E., and Mital A. (2005), for example, used the
heart rateHeart rate is determined by the number of heartbeats per unit of time, typically expressed as beats per minute , it can vary with as the body's need for oxygen changes, such as during exercise or sleep. The measurement of heart rate is used by medical professionals to assist in the diagnosis and...
-
blood pressureBlood pressure is the pressure exerted by circulating blood on the walls of blood vessels, and is one of the principal vital signs. During each heartbeat, BP varies between a maximum and a minimum pressure...
product (RPP) as a measure of both cognitive and physical occupational workload. They believe that it may be possible to use RPP measures to set limits on workloads and for establishing work allowance.
Individual differences in processing capacity
Scandura (1971) and Voorhies & Scandura (1977) found evidence that individuals systematically differ in their processing capacity.
A series of experiments support the assumption that each individual has a fixed capacity for processing information, irrespective of the task in question, or more accurately, irrespective of the processes an individual uses in solving any given task. Tasks ranged from remembering simple lists, lists supplemented with a fixed constant and simple arithmetic.
Identifying the processing capacity of individuals could be extremely useful in further adapting instruction (or predicating the behavior) of individuals. Accordingly, further research would clearly be desirable. First, it is essential to compute the memory load imposed by detailed analysis of the processes to be used. Second, it is essential to ensure that individual subjects are actually using those processes. The latter requires intensive pre-training.
For further reading
- Barrett, H. C., Frederick, D., Haselton, M., & Kurzban, R. (2006). Can manipulations of cognitive load be used to test evolutionary hypotheses? Journal of Personality and Social Psychology, 91, 513-518. Full text
- Cooper, G. (1990) Cognitive load theory as an aid for instructional design. Australian Journal of Educational Technology. 6(2), 108-113.
- Cooper, Graham (1998). "Research into Cognitive Load Theory and Instructional Design at UNSW".
- UNSW Cognitive Load Theory Conference - Sydney Australia 24-26 March 2007
For ergonomics standards see
- ISO 10075-1:2000 Ergonomic Principles Related to Mental Workload - Part 1: General Terms and Definitions
- ISO 10075-2:2000 Ergonomic Principles Related To Mental Workload - Part 2 - Design Principles
- ISO 10075-3:2004 Ergonomic Principles Related To Mental Workload - Part 3: Principles And Requirements Concerning Methods For Measuring And Assessing Mental Workload
- ISO 9241
ISO 9241 is a multi-part standard covering a number of aspects for people working with computers. Although originally titled Ergonomic requirements for office work with visual display terminals it is being retitled to the more generic Ergonomics of Human System Interaction by ISO...
Ergonomics of Human System Interaction
See also
- Cognitive Load Theory
- Extraneous cognitive load
Extraneous cognitive load is the working memory load experienced by learners as they interact with instructional materials. This is a type of cognitive load that instructional designers do have some ability to control...
- Germane cognitive load
Germane cognitive load is that load devoted to the processing, construction and automation of schemas.Germane load was first described by Sweller, van Merrienboer and Paas in 1998...
- Intrinsic cognitive load
Intrinsic cognitive load is the inherent level of difficulty associated with instructional materials.The term "Intrinsic cognitive load" was first described by . According to Chandler and Sweller, all instruction has an inherent difficulty associated with it...
- Workplace stress
Workplace stress is the harmful physical and emotional response that occurs when there is a poor match between job demands and the capabilities, resources, or needs of the worker....
- Task loading
Task loading in Scuba diving is a term used to refer to a multiplicity of responsibilities leading to an increased risk failure on the part of the diver to undertake some key basic function which would normally be routine for safety underwater....
(in scuba divingScuba diving is a form of underwater diving in which a diver uses a scuba set to breathe underwater for recreation, commercial or industrial reasons.Unlike early diving, which relied exclusively on air pumped from the surface, scuba...
)
- video of John Sweller explaining Extraneous load