Memory full

In a recent blogpost entitled Memories are made of this I wrote about how human memory works in different modalities, principally through auditory and visual coding. The emphasis of the Working Memory model, and also Dual Coding Theory is that memories are strengthened when both auditory and visual stimuli are presented to the learner in an optimal combination. I suggested that the addition of text is useful if it doesn't impinge upon and overload WM, which is limited in its capacity. This is quite a simplification, and requires elaboration, so here is the second post in my blog series on learning and memory.

The work of John Sweller and Nillie Lavie on Cognitive Load Theory and Capacity Theory (based on studies by Shalom Fisch) is useful to help us understand how to optimise digital design environments such as the layout of virtual learning environments or online discussion groups. What exactly can Cognitive Load Theory do to help us to optimise students' memories?

To understand Cognitive Load Theory, we first need to revisit Working Memory (WM). Recall that WM is the dual modality temporary (conscious) memory that enables us to attend to and code content, and also to recall content previously stored in Long Term Memory. Lavie discovered that the more stimuli on offer, and the subsequent load placed on WM, the more selective attention performance will be hindered. In other words, there is only so much load WM can take. Mindful of this phenomenon, Sweller recommended that content designers should limit the amount of cognitive load in digital learning environments by strategically presenting worked examples and problem solving exercises.

Another principle is for designers to provide learners with the most appropriate media for every possible component of learning content. For example, to describe a circle in text form would take up a lot more cognitive processing than a picture, and the student would take longer to apprehend the meaning of the words. Seeing a diagram of a circle reduces the cognitive load (thinking effort) and enables the student to learn easier and faster.

The placement and juxtaposition of content on screen is also an important design consideration. The more closely together 'related content' can be presented on screen, the quicker should be the capability of the learner to understand it and remember it later. This is actually a Gestalt principle referred to as the Proximal Law.

How does Capacity Theory apply in digital learning environments? In any educational media presentation, WM (remember it is limited) competes for space to process and code the content. It has to differentiate between educational content and narrative content found in say, a YouTube video. Capacity Theory holds that the more closely aligned the two types of content are, the greater will be the chance that the student will learn more deeply. Thus the distance between narrative and educational content should be reduced as much as possible to promote better learning. This echoes the findings of the Cognitive Load Theory experiments and also mirrors the Gestalt law of proximity.

This is but a brief and superficial look at these theories. If you wish to read further, there are some excellent resources available here and here.

Photo by Rutger Middendorp


Memory full by Steve Wheeler is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.