Known as the brain’s "sketch pad," short-term memory is the bottleneck of learning. If someone wants to learn something, they must process it in short-term memory. But if too much information lands in short-term memory at one time, then our cognitive sketchpad becomes overwhelmed.
When it comes to learning, the takeaway is clear: People gain more if they lessen the demands on their short-term memory. So if someone is learning something, they should limit distractions. Don't listen to jazz. Turn off your cell phone. Stay away from Twitter.
The limits of short-term memory also explain why instructors are so important for learning. As this video will explain: Great educators explain skills and knowledge in ways that don't overwhelm short-term memory.