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In this week’s Science of Learning article we’re focusing on a fundamental best practice in developing content: segmenting.

If you’re familiar with the work of Richard E. Mayer, you might recognize that term; it comes up quite often in his research. The segmenting principle refers to the recommendation to break e-learning lessons and videos into manageable parts that the learner can process before moving on to the next segment. Why? Mayer & Clark (2016) explain it thusly:

When an unfamiliar learner receives a continuous presentation containing a lot of inter-related concepts, the likely result is that the cognitive system becomes overloaded… the amount of essential cognitive processing needed to make sense of the essential material exceeds the learner’s cognitive capacity. (p. 206)

So, where’s the evidence to support the claim from Mayer & Clark? They reference a few studies, including:

  • Mayer & Chandler (2001): learners who received segmented content performed better on assessments than learners who received the same content in one long presentation

  • Moreno (2007): learners who viewed a 20-minute video performed worse on assessments than students who received the identical video broken into 3-minute segments where each video focused on one principle

Mayer also cites his own meta-analysis, conducted with Pilegard (2014), which found that in ten out of ten published experiments, learners who received content in segments performed better on assessments than those who received the same content in continuous form.

So, what does this mean for instructional designers? Chunk it up. Don’t expect learners to sit through a lengthy 20-minute video; not only are they likely to get bored, their brains are less likely to remember what they’ve watched, reducing both near and far transfer. Break your content up into smaller chunks (less than 3 minutes) that introduce one singular principle; that way, learners can pause, think about what they’ve watched, and then continue their learning at their own pace.

Want to read more? Check out e-Learning and the Science of Instruction: Proven Guidelines for Consumers and Designers of Multimedia Learning (2016) by the illustrious duo Ruth Colvin Clark and Richard E. Mayer, or read one of the many studies cited in the text: