Acute stress, such as that experienced during an exam, significantly impairs a person’s ability to link past memories with newly acquired information. A recent study published in the journal Science Advances<\/i>, which combined psychological testing and brain scanning, explains this phenomenon in detail. For the first time, scientists were able to witness in real time how intense emotional pressure disrupts access to prior experiences and logical deduction.<\/p>\n
Our minds connect new and old information through a cognitive process known as “integration,” which helps us perceive cause-and-effect relationships in daily life. A specific area in the brain\u2014the hippocampus\u2014is responsible for executing this complex function. Since this region is particularly sensitive and vulnerable to stress, researchers from the University of Hamburg decided to investigate exactly what happens to it under pressure.<\/p>\n
Neuroscientists developed a unique two-day experimental method involving 121 volunteers. On the first day, participants were given a simple task: they had to memorize pairs of photographs showing a specific animal alongside either a person’s face or a landscape. This established the baseline that the brain would later need to build a logical chain.<\/p>\n
On the second day of the experiment, half of the participants were placed in a simulated, acutely stressful environment. They underwent a mock job interview where they had to defend their candidacy under intense scrutiny while simultaneously performing complex mathematical calculations in their heads. Meanwhile, the second group\u2014the control group\u2014was asked to simply speak on a free topic and complete basic tests in a completely calm atmosphere.<\/p>\n
Immediately after the stressful phase, all participants were presented with new pairs, where the familiar animals were now linked to new, 3D geometric shapes. In the final stage, scientists showed the volunteers only these shapes and asked them to guess which face or landscape from the first day corresponded to them. The brain had to bridge the old and new memories using the animal’s image as a link.<\/p>\n
To observe these processes, scientists utilized functional magnetic resonance imaging (fMRI), which visually captured brain activity in real time. It revealed that within the hippocampus of stressed individuals, the specific subregion responsible for associating faces and landscapes was barely activated. Under normal conditions, receiving new information ignites a certain “spark” of past experience in the brain; under stress, however, this neuronal spark simply vanishes.<\/p>\n
Interestingly, the accuracy of the test results remained equal between the stressed and calm groups. The authors explain that fMRI scanning is far more sensitive, detecting failures at the neuronal level before they visibly manifest in human behavior. The scientists plan to continue their research on rodents to discover specific pathways that can protect the brain from this harmful impact of stress.<\/p>\n