Why a small amount of anxiety could improve your memory

For people with an anxiety disorder, everyday tasks can seem impossible. In its worst form, anxiety can cause trouble sleeping, heart palpitations, or the inability to leave the house.

But in smaller amounts, the kind of everyday anxiety we all feel from time to time can be used in positive ways. For example, we can learn to channel it and use it as a tool to aid our performance at work or in our personal lives.

According to new research, a small amount of anxiety could also help us remember things better.

In the new study, published in the journal Brain Sciences, researchers from the University of Waterloo recruited 80 students, who were assessed using the Depression Anxiety Stress Scales. They were randomly assigned into two groups: a deep encoding group and a shallow encoding group.

In memory research, shallow processing refers to the sounds and structure of language, whereas deep processing is when we hear a word and work out its meaning. This deep processing, called semantic processing, is how our brain connects words we just heard to other words with similar meanings, which makes us remember them better.

The participants were shown 72 words overlayed on pictures that were either negative or neutral — a car crash vs an orange boat, for example.

Those in the shallow encoding group were asked to look for the letter "a," whereas those in the deep encoding group were asked whether the word represented a living or non-living object.

The results showed that manageable levels of anxiety aided participants' memory, and they were better able to recall details. In the shallow encoding group, where participants were not as likely to remember words as well, those with high anxiety remembered words better when they were paired with negative images.

"To some degree, there is an optimal level of anxiety that is going to benefit your memory," said Myra Fernandes, professor in the Department of Psychology, and coauthor of the study. "But we know from other research that high levels of anxiety can cause people to reach a tipping point, which impacts their memories and performance."

In other words, if anxiety is too high, or it turns into fear, this can lead to people's memories becoming tainted, and the benefit is no longer there.

One limitation of the study that the authors note is that people may perceive images differently. There were a variety of pictures deemed as "negative," but what one person sees as a potential threat may not be the same for another person.

Future studies, they say, could look at how people with specific phobias react to words overlayed on images of the things they are scared of. For example, seeing if arachnophobes remember words better when they are placed over images of spiders.