Stress is commonly linked with emotional exhaustion and poor mental health, but a new study suggests a little bit of it can be good for our brain function.
In experiments involving brain scans, researchers in the US found stress can positively benefit our ‘working memory’ in certain circumstances.
The working memory is the mental ‘notepad’ that contains fleeting thoughts and is responsible for the temporarily holding and processing of information.
Humans have a sweet spot known as the ‘hormetic zone’ where stress can actually improve our working memory – but if stress gets too high it can have a ‘toxic’ effect on cognitive function, the researchers found.
Stress is commonly linked with emotional exhaustion and poor mental health, but a new study suggests a little bit of it can be good for our brain function (file photo)
Humans have a sweet spot known as the ‘hormetic zone’ where stress can actually improve cognitive functioning – but if stress gets too high it can have a ‘toxic’ effect on our brain
The new research has been led by experts at the University of Georgia in Athens and published in the journal Neuropsychologia.
‘Low-to-moderate levels of stress benefit working memory (WM),’ they say in their paper.
‘This study highlights emerging evidence of a process by which mild stress induces neurocognitive benefits.’
For the study, researchers examined the neural responses of 1,000 young adults, between the ages of 22 and 37, during a working memory challenge.
The challenge, known in psychology as n-back, involves subjects being presented with a sequence of stimuli and indicating when the current stimulus matches the one from steps earlier in the sequence.
Participants underwent functional magnetic resonance imaging (fMRI) scans – which measure brain activity by detecting changes associated with blood flow – during the working memory task to determine stress levels.
Participants’ also reported to what extent they felt ‘that their lives are stressful and beyond control’ and were assessed for four ‘psychosocial resources’ that influence how people manage stressful events.
These psychosocial resources were ‘self-efficacy’ (confidence in one’s own capabilities), ‘meaning and purpose’ (a feeling their own lives matter and are meaningful), ‘friendship’ (perception of the availability of companionship from friends) and ‘instrumental support’ (availability of a social network to provide material support or help).
Participants underwent functional magnetic resonance imaging (fMRI) scans during a working memory task to determine their stress levels
The team found that those who reported low-to-moderate levels of perceived stress showed increased neural activation in a working memory network of the brain during a task, as well as increases in behavioural performance.
However, the strength of this association plateaued at high-stress levels, suggesting stress only helps brain cognition to a certain degree before it gets too high.
Extreme levels of stress are harmful to working memory’s ‘neural and behavioral functioning’, the team say in their paper.
Additionally, the benefits of low-to-moderate stress were stronger among individuals with access to higher levels of the four psychosocial resources.
‘Psychosocial resources are potent protective factors as they mitigate the severity of stress (making it less severe and more controllable),’ they add.
‘Such a buffering effect prevents stress from becoming toxic.’
Researchers conclude that the ‘potential neurocognitive benefits’ caused by stress are less investigated than the detrimental effects.
Previous studies on rats have already demonstrated a link between mild stress and improved memory performance, they add.