In “The Magical Number 4 in short-term memory” Cowan (2002) discusses the concept of whether there is a limitation to the human capacity to store and process information. The basis of his discussion originates in Miller’s (1965) “The Magical Number Seven, Plus or Minus Two”. Both Cowan and Miller argue that there is a limit to the number of items, or “chunks” of related items, we can store in short term memory. While it is important to consider the concept of a limitation to the amount of information we can store in short term memory, the question of how we combine chunks, and convert short-term memory to long-term memory may have a larger impact on Human Computer Interaction (HCI) and the development of effective learning environments.

Cowen (2000) indicates that long term memory information can be used to create larger chunks out of smaller ones. As we are exposed to new information, assimilate and use that information, we create strong associations that allow us to store those items in long term memory and retrieve that information as related chunk of information. Using this as a premise we can then look at design from the perspective of grouping like items together and developing associations to previous information as a product or learning environment is explored.

In “Moonwalking with Einstein”, Joshua Foer (2011) discusses the concept of memory mapping. Memory mapping is the process of creating building blocks, or associations, in long term memory that can be used as storage points to attach short term memory items. The question now becomes, “How can we create building blocks in our designs that will allow users to create chunks that can be more readily remembered and assimilated into long-term memory.

Using Miller and Cowan’s premise that the maximum number of items that can be retained in short-term memory is somewhere between four and seven, we should consider designs that incorporate no more than four to seven individual elements. Larger numbers of elements can be combined together by creating associations that allow users to combine them into chunks, thereby freeing up short term memory for new items.

Cowan, N. (2001). The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Behavioral and brain sciences, 24(1),87-185.

Miller, G. A. (1956). The magical number seven, plus or minus two: some limits on our capacity for processing information. Psychological review, Vol 63(2).

Foer, Joshua. (2011). Moonwalking with Einstein: The Art and Science of Remembering Everything. Penguin Press.