When individuals use websites or other interfaces, a common issue they face is forgetting information from a prior step that is necessary to complete their task later on. This doesn't happen because users are particularly forgetful, nor is it because they don't pay attention. However, the user interface can require users to keep more information in their working memory than their brains can handle.
For example, if someone asked you to add the numbers 353 and 489 in your head, it would be a challenging task. Some individuals may mentally line up the numbers and add the corresponding digits for units, tens, and hundreds, while others may transform one of the numbers into an "easy"number and then add it to the other. Regardless of the method used, the task requires keeping a lot of information in working memory, including the exact numbers to be added and the intermediate products of the addition. This task is difficult because it taxes our working memory, which has limited capacity.
Human working memory can be viewed as a buffer or scratchpad where the mind stores relevant information for the current task. This buffer has a limited number of slots, similar to an egg carton, and if a task requires too much information to be kept in working memory, we need to free up some slots to make space for that information. Unfortunately, what is removed from working memory may still be necessary to complete the task, and we may need to work harder to recover that information, resulting in longer task completion times or mistakes. In the example of adding 353 and 489, we may end up forgetting a carry or digit from one of the original numbers and producing the incorrect answer.
The concept of working memory was first demonstrated in a series of experiments by psychologists Alan Baddeley and Graham Hitch from the University of Stirling in Scotland. Participants were given 1 to 6 digits to remember while performing a different task where they had to determine if a sentence matched the order of presentation of two letters. As the number of digits to remember increased, participants performed worse on the second task. This experiment suggested that part of the participants'working memory was being used to store the digits, leaving fewer slots available for the second task.
This process is similar to thrashing in computer science, where the processor doesn't have enough internal memory to store all the information for a task, resulting in repeated dumping of part of the information on the disk and loading of other information from the disk.
In summary, working memory is a crucial component of our cognitive processes, but it has its limits. User interfaces that require individuals to holding too much information in working memory can be problematic, resulting in longer task completion times or errors. Understanding the limitations of Working memory can help us design more user-friendly interfaces that minimize the cognitive load on users.
Working memory and short-term memory are related, and the terms are sometimes used interchangeably. However, they are technically distinct.
Working memory can be thought of as an interface between different cognitive processes, whereas short-term memory is the process of temporarily storing information.
Short-term memory is associated with chunking and Miller's magical number 7, which represents the approximate capacity of short-term memory to hold about 7 chunks of information for a brief period of time.
While working memory and short-term memory are sometimes used interchangeably, they are technically distinct concepts. Working memory can be seen as an "interface" that facilitates communication between different cognitive processes, all of which work towards a larger goal or task. On the other hand, short-term memory refers to the brain's ability to temporarily hold information, such as words, sentences, or concepts. One well-known concept related to short-term memory is chunking, and George Miller's famous "magical number 7" theory posits that we can remember approximately 7 pieces of information in short-term memory at a time.
Baddeley, A.D., & Hitch, G. (1974). Working memory. In G.H. Bower (Ed.),The psychology of learning and motivation: Advances in research andtheory (Vol. 8, pp. 47–89). New York: Academic Press.