why instructional design doesn’t typically work with students, or anyone’s learning for that matter, when you teach with PowerPoint—as well as how you can avoid it. It all begins with a little concept called “cognitive load.”
Cognitive load describes the capacity of our brain’s working memory (or WM) to hold and process new pieces of information. We’ve all got a limited amount of working memory, so when we have to handle information in more than one way, our load gets heavier, and progressively more challenging to manage.
In a classroom, a student’s cognitive load is greatly affected by the “extraneous” nature of information—in other words, the manner by which information is presented to them (Sweller, 2010). Every teacher instinctively knows there are better—and worse—ways to present information.
A study in Australia in the late 1990s (the 1999 Kalyuga study) compared the learning achievement of a group of college students who watched an educator’s presentation involving a visual text element and an audio text element (meaning there were words on a screen while the teacher also talked) with those who only listened to a lecture, minus the pesky PowerPoint slides.
Researchers including John Sweller and Kimberly Leslie contend that it would be easier for students to learn the differences between herbivores and carnivores by closing their eyes and only listening to the teacher. But students who close their eyes during a lecture are likely to to called out for “failing to paying attention.”
Richard Mayer, a brain scientist at UC Santa Barbara and author of the book Multimedia Learning, offers the following prescription: Eliminate textual elements from presentations and instead talk through points, sharing images or graphs with students
a separate Australian investigation by Leslie et al. (2012), suggest that mixing visual cues with auditory explanations (in math and science classrooms, in particular) are essential and effective. In the Leslie study, a group of 4th grade students who knew nothing about magnetism and light learned significantly more when presented with both images and a teacher’s explanation than a separate group which received only auditory explanation.
Limit yourself to one word per slide. If you’re defining words, try putting up the vocabulary word and an associated set of images—then challenge students to deduce the definition.
Honor the “personalization principle,” which essentially says that engaging learners by delivering content in a conversational tone will increase learning. For example, Richard Mayer suggests using lots of “I’s” and “you’s” in your text, as students typically relate better to more informal language.
Cognitive load theory is built upon two commonly accepted ideas. The first is that there is a limit to how much new information the human brain can process at one time. The second is that there are no known limits to how much stored information can be processed at one time. The aim of cognitive load research is therefore to develop instructional techniques and recommendations that fit within the characteristics of working memory, in order to maximise learning.
Explicit instruction involves teachers clearly showing students what to do and how to do it, rather than having students discover or construct information for themselves
how working memory and long-term memory process and store information
Working memory is the memory system where small amounts of information are stored for a very short duration (RAM). Long-term memory is the memory system where large amounts of information are stored semi-permanently (hard drive)
Cognitive load theory assumes that knowledge is stored in long- term memory in the form of ‘schemas’ 2 . A schema organises elements of information according to how they will be used. According to schema theory, skilled performance is developed through building ever greater numbers of increasingly complex schemas by combining elements of lower level schemas into higher level schemas. There is no limit to how complex schemas can become. An important process in schema construction is automation, whereby information can be processed automatically with minimal conscious effort. Automaticity occurs after extensive practice
Schemas provide a number of important functions that are relevant to learning. First, they provide a system for organising and storing knowledge. Second, and crucially for cognitive load theory, they reduce working memory load. This is because, although there are a limited number of elements that can be held in working memory at one time, a schema constitutes only a single element in working memory. In this way, a high level schema – with potentially infinite informational complexity – can effectively bypass the limits of working memory
Types of cognitive load
Cognitive load theory identifies three different types of cognitive load: intrinsic, extraneous and germane load
Intrinsic cognitive load relates to the inherent difficulty of the subject matter being learnt.
subject matter that is difficult for a novice may be very easy for an expert.
Extraneous cognitive load relates to how the subject matter is taught.
extraneous load is the ‘bad’ type of cognitive load, because it does not directly contribute to learning. Cognitive load theorists consider that instructional design will be most effective when it minimises extraneous load in order to free up the capacity of working memory
Germane cognitive load refers to the load imposed on the working memory by the process of learning – that is, the process of transferring information into the long-term memory through schema construction
the approach of decreasing extraneous cognitive load while increasing germane cognitive load will only be effective if the total cognitive load remains within the limits of working memory