Low to Moderate Stress Improves Memory Function

Psychological stress has a dose response curve in which it is beneficial for some functions at low levels, it seems. This is not a complete surprise, given that hormesis seems to be a universal phenomenon. Mild or short-lived stress produces a lasting protective reaction that more than compensates for any harms caused by the stress, improving cell and tissue function. Here researchers show evidence for low levels of stress to improve memory. We might suspect this effect to be mediated by increased blood flow to the brain, given the copious evidence for improved memory function to result from increased cerebral blood flow, such as resulting from exercise. Portions of the brain operate at the very edge of their supply of nutrients and oxygen, even in youth.

The negative impact of stress on neurocognitive functioning is extensively documented by empirical research. However, emerging reports suggest that stress may also confer positive neurocognitive effects. This hypothesis has been advanced by the hormesis model of psychosocial stress, in which low-moderate levels of stress are expected to result in neurocognitive benefits, such as improved working memory (WM), a central executive function. We tested the hormesis hypothesis, purporting an inverted U-shaped relation between stress and neurocognitive performance, in a large sample of young adults from the Human Connectome Project (n = 1000, mean age 28.74).

In particular, we investigated whether neural response during a WM challenge is a potential intermediary through which low-moderate levels of stress confer beneficial effects on WM performance. Further, we tested whether the association between low-moderate prolonged stress and WM-related neural function was stronger in contexts with more psychosocial resources. Findings showed that low-moderate levels of perceived stress were associated with elevated WM-related neural activation, resulting in more optimal WM behavioral performance. The strength of this association tapered off at high-stress levels. Finally, we found that the benefit of low-moderate stress was stronger among individuals with access to higher levels of psychosocial resources.

By drawing attention to the dose-dependent, nonlinear relation between stress and WM, this study highlights emerging evidence of a process by which mild stress induces neurocognitive benefits, and the psychosocial context under which benefits are most likely to manifest.

Link: https://doi.org/10.1016/j.neuropsychologia.2022.108354

Comment Submission

Post a comment; thoughtful, considered opinions are valued. New comments can be edited for a few minutes following submission. Comments incorporating ad hominem attacks, advertising, and other forms of inappropriate behavior are likely to be deleted.

Note that there is a comment feed for those who like to keep up with conversations.