Why can't I remember something so quickly?

Can we specifically forget?

Deliberately deleted: Apparently people can consciously forget information. Accordingly, the pure intention to erase something from memory is sufficient - and the corresponding content has actually disappeared. Particularly astonishing: this effect has a lasting effect. It makes remembering even more difficult in the long term than unexpected distractions.

Remembering is a complex and dynamic process. Because we are constantly exposed to new information in everyday life, our short-term memory, in particular, is in constant change: the cache continuously adapts to changes in our environment - and new content pushes old ones into the background.

How well we can remember something depends on various factors: An unexpected distraction can make you forget the telephone number you just remembered and emotions and stress also have a strong influence on our memory. All of these processes usually take place unconsciously. But is it also possible for us to consciously change our memory - for example to delete information in a targeted manner?

Task: Forget it!

Scientists working with Karl-Heinz Bäuml and Magdalena Abel from the University of Regensburg have now asked themselves this question. In order to be able to answer them, they had a total of 360 test subjects line up for a memory experiment. The task: All test persons should memorize two word lists one after the other.

After internalizing the first list, however, the participants received different tips: The first third was asked, without further comments, to remember the words on both lists until the end of the experiment. The second third, however, was distracted: they should first draw a sketch of their parents' house before they started studying the second list. And the hint for the third group was: Forget the first list, because we had a computer crash and unfortunately have to restart the experiment.

Actually deleted

How well would the information from the first list be remembered by the three groups of subjects? This was shown in a test in which the participants were asked to remember the words on the two lists - three minutes after the end of the experiment, 20 minutes afterwards and 24 hours later.

The result: The participants from the third group were the worst at remembering the words. Apparently, the specific hint to forget had actually caused them to forget the outdated information. After all time intervals, this content appeared to have been erased from short-term memory. In contrast to this, the diversionary maneuver caused by the change in context only had a short-term effect in group two: although the memory was initially also difficult, as expected, it returned very quickly.

Amazingly sustainable

The results show that people can deliberately forget - and that this deliberately brought about process is surprisingly sustainable. In the future, the researchers would like to investigate further how updating processes work in our memory. The long-term effect of conscious memory updates also suggests that this effect should also be used in educational contexts, they conclude.

(University of Regensburg, January 18, 2017 - DAL)

18th January 2017