Carried out by researchers from Penn State University, the new study recruited 240 adults and followed them for a period of two weeks.
During this time the participants were asked to respond to questions sent to them seven times a day via a smartphone app, including one question in the morning asking them about whether they expected their day to be stressful, five questions throughout the day about their current stress levels, and one question at night about whether they expected the following day to be stressful.
The participants also completed five tests a day to assess working memory, which is the temporary storage and managing of information in the brain.
The responses showed that when participants woke up feeling like their day ahead would be stressful, their working memory was lower later in the day, even if no stressful events actually occurred.
However, stress anticipation from the previous evening was not associated with poorer working memory.
Jinshil Hyun, one of the study’s co-authors, said the findings suggest that the stress process begins long before a stressful event occurs.
“Humans can think about and anticipate things before they happen, which can help us prepare for and even prevent certain events,” explained Hyun. “But this study suggests that this ability can also be harmful to your daily memory function, independent of whether the stressful events actually happen or not.”
Martin Sliwinski, who also worked on the study, added, “When you wake up in the morning with a certain outlook for the day, in some sense the die is already cast. If you think your day is going to be stressful, you’re going to feel those effects even if nothing stressful ends up happening. That hadn’t really been shown in the research until now, and it shows the impact of how we think about the world.”
Sliwinski also explained that a reduction in working memory can affect many aspects of a person’s day to life, especially for older adults who already experience cognitive decline.
“A reduced working memory can make you more likely to make a mistake at work or maybe less able to focus. Also, looking at this research in the context of healthy aging, there are certain high stakes cognitive errors that older adults can make. Taking the wrong pill or making a mistake while driving can all have catastrophic impacts.”
“If you wake up and feel like the day is going to be stressful, maybe your phone can remind you to do some deep breathing relaxation before you start your day,” Sliwinski said. “Or if your cognition is at a place where you might make a mistake, maybe you can get a message that says now might not be the best time to go for a drive.”