Summary: Low-to-moderate stress can enhance certain brain functions—particularly working memory—while sustained high stress becomes harmful.
Source: University of Georgia
The holiday season and other busy times often bring added pressure, but new research from the Youth Development Institute at the University of Georgia suggests that not all stress is bad for the brain.
Researchers found that low-to-moderate levels of stress were associated with improved working memory—the short-term mental process used to hold and manipulate information, such as remembering directions or a phone number long enough to act on it.
However, the benefit applies only up to a point. The study emphasizes a clear distinction: when stress becomes high and persistent, it shifts from potentially helpful to damaging.
“The harmful consequences of chronic stress are well established,” said Assaf Oshri, the study’s lead author and an associate professor in the College of Family and Consumer Sciences. “Long-term high stress can alter brain structure and function.”
Chronic stress has been linked to structural brain changes—such as shifts in white and gray matter balance—that can impair decision-making, emotional regulation, self-control and motor functions. It also raises the risk for physical ailments, including headaches, digestive issues, high blood pressure and heart disease.
“But we know less about the effects of short-term, limited stress,” Oshri added. “Our results indicate that low-to-moderate perceived stress is tied to stronger neural activation in working memory circuits, which translates into better mental performance in those tasks.”
Previous work by Oshri and colleagues suggested that manageable stress exposure can build resilience and lower the likelihood of developing mood or behavioral problems. Those studies proposed that limited stress episodes help people develop coping skills for future challenges. The current study advances that idea by using brain imaging to show how modest stress levels engage working memory networks more effectively.
Social support helps people handle stress in healthier ways
The team analyzed MRI scans and behavioral data from more than 1,000 participants drawn from the Human Connectome Project, a large NIH-funded effort to map brain connectivity. The diverse sample allowed the researchers to examine how perceived stress relates to brain activation during working memory tasks.
Participants who reported low-to-moderate stress showed increased activation in brain regions that support working memory. In contrast, those reporting chronic, high stress showed reduced activation in those same areas, alongside poorer task performance.
Perceived stress was measured by asking how often participants experienced specific feelings or reactions during the prior month—for example, how often they were upset by unexpected events or felt unable to cope with everything they had to do. The study used established survey items that are commonly applied in international research on stress and coping.
The researchers also assessed participants’ social resources, measuring factors such as perceived competence in handling unexpected events, a sense of life meaning, and the availability of friend-based support. Those with stronger social ties and psychosocial resources appeared better equipped to gain cognitive benefits from low-to-moderate stress without tipping into harmful effects.
To evaluate working memory, participants completed a recognition task that presented four categories of images—objects like tools and faces—and later asked whether shown images matched those seen earlier. While participants performed the task, MRI scans tracked neural activation patterns across brain regions involved in working memory.
Results indicated an inverted U-shaped relationship between stress and working memory: modest stress levels were linked to heightened neural engagement and improved behavioral performance, but those gains diminished at high-stress levels. Importantly, the positive effects of moderate stress were stronger among individuals who reported more psychosocial support.
“Adversity and stress can strengthen some people, but they can overwhelm others,” Oshri noted. “Access to supportive family, friends or community resources makes it more likely that limited stress will be beneficial rather than harmful.”
About this stress and memory research news
Author: Press Office
Source: University of Georgia
Contact: Press Office – University of Georgia
Image: The image is in the public domain
Original Research: Open access.
“Low-to-moderate level of perceived stress strengthens working memory: Testing the hormesis hypothesis through neural activation” by Assaf Oshri et al., published in Neuropsychologia.
Abstract
Low-to-moderate level of perceived stress strengthens working memory: Testing the hormesis hypothesis through neural activation
While the negative effects of high stress on cognitive function are well documented, emerging evidence suggests that modest stress exposure may offer neurocognitive benefits. The hormesis model of psychosocial stress proposes an inverted U-shaped relation between stress and performance, where low-to-moderate stress enhances functions like working memory (WM) but high stress impairs them.
This study tested that hypothesis in a large sample of young adults from the Human Connectome Project (n = 1000, Mage = 28.74, SD = 3.67, 54.3% female). Researchers examined whether neural responses during a WM challenge mediate any beneficial effects of modest perceived stress on WM performance, and whether psychosocial resources strengthen this association.
Findings showed that low-to-moderate perceived stress was linked to elevated WM-related neural activation and more optimal WM performance. This benefit weakened at higher stress levels. Additionally, the positive effect of modest stress was more pronounced among individuals with greater psychosocial resources. These results highlight a dose-dependent, nonlinear relation between stress and working memory, and point to the social context as a key factor in whether mild stress leads to cognitive gains.