The famous George Miller paper ‘The Magic Number 7 Plus and Minus Two’ has turned out to be rather optimistic. In practice, research from the
Working memory is what we use most of the time to function and is critical in problem solving and maths as we need to hold several items in the mind for comparison and manipulation. We know that we have as little as three or four working registers so if we store IFCMBAIBI as IBM-CIA-FBI, it’s easy. This article appeared in April’s Proceedings of the National Academy of Sciences.
This has important ramifications in learning as it lowers the bar on the possibility of cognitive overload. The lesson is that fewer items need to be presented at any one time and that chunking becomes very important.