Cognitive Load Theory

     At some point in your educational or business career you have probably left a class or training session feeling overwhelmed, frustrated or distracted. As adult educators we  know that instructional design practices, that do not take into account the limitations of the learners' working memory, can lead to trainings or classes that are ineffective.      

     Your working memory may have been overloaded by power point slides with images that didn't seem to be connected or relevant to the topic, contained too many bulleted points and sub-points, or verbal directions were given while you were trying to follow a handout or concentrate on a task using a computer. This can be compounded by the distractions of a noisy and/or uncomfortable learning environment. Our working memory is limited and easily becomes overloaded when bombarded with too much during an instructional event.

     Many educators today have read or are aware of George A. Miller's famous article, The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information. But are we aware of the depth of research underlying the human memory processing system? John Sweller, Ph.D., a psychologist from Australia, has conducted research and written prolifically over the past 40 years on Cognitive Load Theory. When searching through journals and other publications, it was not possible to find an article or paper on CLT that was not co-authored by him or one in which his work was not cited.

Sweller's research and writing has focused on the relationship between human cognitive architecture, the differences in memory processing between experts and novices, and cognitive load. Cognitive Load Theory, by Sweller, Ayres and Kalyuga, is a comprehensive work on cognitive load theory and a guide for instructional design practices based on research for developing and designing instruction that minimizes the impact of our limited working memory and optimizes learning.

     In Cognitive Load Theory, Sweller, Ayres and Kalyuga describe the complexity of the human cognitive information system by comparing it with evolutionary biology (2011). They believe that the frequently used computer analogies employed to explain how humans process information are overly simplistic and not adequate to explain the complexity and the vast variety and amount of information it processes. Just as a genome carries all the inherited traits of an organism; all the information it needs to survive, they believe the human cognitive system must be equally large and complex (Sweller, et al., 2011). They found many of the models, like the computer model, used to explain human cognitive architecture artificial. Because our human cognitive information system is a naturally occurring system, to understand it they looked at other naturally occurring systems, like biological evolution and compared underlying principles of both systems (Sweller, et al., 2011). 

 

What is Learning?

     Sweller defines learning as a change in long term memory and when change does not occur learning has not occurred (2011). Simply stated, learning results when new information is processed by working memory, is transferred to long term memory, and can be retrieved when needed later. The capacity of working memory for new information is limited to a small amount as George A. Miller discovered; working memory, on average was limited to seven bits and could be as little as four (Miller, 1956). Research also indicates that this limited amount of information can only be stored in working memory for a short period of time; possibly as short as 30 seconds (Kirschner, Sweller, & Clark,  2006).

     On the other hand, the amount of information working memory is able to process does not seem to be limited when retrieving information from long term memory into working memory (Kirschner et al., 2006). Studies by DeGroot, conducted in 1945 and again in the 1960s, of expert and novice chess players suggested that experts' skills come from retrieving information from past experiences stored in long term memory (Kirschner et al., 2006). The novice does not possess this knowledge and, therefore, their working memory capacity is limited because the problem they are faced with solving is new to them. Their working memory is occupied by finding ways to solve the problem. The expert is not using working memory to process new information but instead is retrieving information from a large storage of past experience and prior knowledge.

 

Impact on Instructional Design

     Sweller finds much to criticize about constructivist instructional design based on problem-based learning. He views unsupported or unguided instruction as resulting in learners focusing on developing problem-solving skills rather than the knowledge they are expected to learn (Kirschner et al., 2006; Sweller et al., 2011). A second criticism of problem-based learning is that learners can develop less than accurate schema when not presented with all the information. John Dewey in his book Experience and Education, agreed that not all experiences were educative and could possibly be "mis-educative" (Dewey, para. 2, 1938). This, indeed, is the problem that cognitive load theorists have with constructivist instructional design; that learners left to discover facts and information on their own through self-directed learning or discovery activities will not gain knowledge but will result in learners developing incorrect schema or information that is secondary to the content, such as problem-solving.

     A point of difference between cognitive load theorists and cognitive constructivists is the distinction cognitive load theorists make between primary and secondary knowledge. Cognitive load theorists, such as Sweller, view primary knowledge as the skills and knowledge humans are naturally programmed to acquire, like learning our first language (Sweller et al., 2011). Because we are naturally programmed to acquire primary knowledge there is no cognitive load to learning these skills unlike secondary knowledge that he believes requires direct, fully-supported instruction. Learning secondary information is impacted by the small capacity of our working memories. CLT is only concerned with the acquisition of secondary knowledge

 

CLT Informs Teaching and Learning

     Sweller believes the aim of instruction should be to reduce unnecessary working memory load and that can be accomplished through well designed, supported or guided instruction (Sweller et al., 2011). A 2004 study by David Klahr and Melina Nigam supports Sweller's findings on direct instruction. Their study measured the effectiveness between direct instruction and discovery learning amongst 112, third and fourth grade students in science classes. Their findings indicated that direct instruction resulted in more learning than the discovery method of instruction (Klahr & Nigam, 2004). 

     Another method of providing instructional support that can reduce the impact of the small capacity of working memory is rehearsal. Not only does rehearsal lengthen the time information can be held in working memory but also assists in transferring information to long term memory, which is the goal of learning; making a change in long term memory.

 

Conclusion

     Dr. Sweller's life work has centered on Cognitive Load Theory and its impact on instructional design. We have all probably experienced, at some point in our educations, poorly designed instruction. Possibly we have even created instructional sessions and felt afterward that learners did seem to learn or retain the information they needed. Even though Sweller does not support the constructivist method of teaching, an educator who believes in constructivism would still find suggestions for designing instruction from this book and many journal publications that would improve learning outcomes. Sweller's research illustrates the importance of designing instruction with an understanding that we all have a very limited working memory and finding methods of improving learning transfer for our learners is one of the principles of effective adult education.

     John Sweller, born in 1946, received his Ph. D. in psychology in 1972 from the University of Adelaide in Adelaide, South Australia. His work in Cognitive Load Theory began in the early 1980s. Dr. Sweller is currently an Emeritus Professor of Education at the University of New South Wales, Sydney, Australia (UNSW School of Education Faculty of Arts and Social Sciences, 2014).  The short bio on the University of New South Wales School of Education website states that he has written over 80 publications; the body of his work has been on CLT and instructional design (UNSW School of Education Faculty of Arts and Social Sciences, 2014).

 

References

Dewey, J. (1938). Experience and education. [Kindle edition]. Retrieved from http://www.amazon.com

 

Kirschner, P.A., Sweller, J., & Clark, R. E. (2006). Why minimal guidance during instruction does not work: An analysis of the failure of constructivist, discovery, problem-based, experiential, and inquiry-based teaching. Educational Psychologist, 41(2), 75-86.

 

Klahr, D., & Nigam, M. (2004). The equivalence of learning paths in early science instruction: Effects of direct instruction and discovery learning. Psychological Science, 15, 661-667.

 

Miller, G.A. (1956). The magical number seven, plus or minus two: Some limits on our capacity for processing information. Psychological Review, 63, 81-97.

 

Sweller, J., Ayres, P., & Kalyuga, S. (2011). Cognitive load theory: Exploration in the learning sciences, instructional systems and performance technology [Kindle edition]. Retrieved from http://www.amazon.com

 

UNSW School of Education Faculty of Arts and Social Sciences. (2014). Emeritus Professor John Sweller. Retrieved from https://education.arts.unsw.edu.au/about-us/people/john-sweller/