Answer: An Uncompleted Task

Among the many cognitive biases that effect our memories, there’s a particularly interesting one that you might not anticipate because it seems counterproductive: we’re better at remembering the details of tasks that are interrupted.

While interruption would seem to be the antithesis of forming reliable memories, psychologist Bluma Zeigarnik (shown above) conducted a series of studies in the early 20th century after her colleague Kurt Lewin had noticed something he found odd and interesting. Lewin noticed that a waiter had a remarkable recollection of what patrons had ordered while a tab was open, but as soon as the tab was closed, he seemed to lose nearly all recollection of the specifics of the interactions.

Through Zeigarnik’s studies, it was established that during a task, the mind is under tension to juggle all the relevant details of the task and if interrupted before the task was completed, commit more of those relevant details to memory. If the task were seen through to completion, fewer of those details, now no longer as relevant, were remembered later. The completion of the task relieves the tension and our brains are less likely to store the information.

The Zeigarnik Effect has a practical application in terms of increasing our recall of information. If we interrupt our studies with unrelated tasks (instead of completing study sessions without a break), there is a higher chance we will recall that information later.