Stress slows your reaction to danger, new study finds, increasing vulnerability

Suffering stressful events may compromise the body’s perception of new threats or danger, a study in Proceedings of the National Academy of Sciences has revealed. 

The study carried out by a team of researchers at the New York University challenges a long-held notion that stress keeps the body on high alert. The researchers have noted that while predicting potential threats in the environment is crucial for survival, it remains equally important to prime the body into a flexible state where stress responses can be effectively controlled when new sources of threat are available.

The research team conducted a series of tests that focused on “Pavlovian threat-conditioning” in order to examine the participant’s flexibility in responding to stressful conditions. The experts instructed the participants to view images on a computer screen. The experts then used a mild, electric wrist-shock that accompanied a certain image that served as the threat cue. On the other hand, some images did not accompany any shock and served as the safe cue.

Half of the study participants were placed in an experimental set-up designed to replicate a stressful condition. During the procedure, the participants in the stress group placed their arm in an ice-water bath for a few minutes. The procedure was intended to increase the respondents’ two stress hormones alpha-amylase and cortisol. All the participants eventually went through the same stress test. The scientists then recorded the participants’ physiological arousal responses to evaluate how they anticipated the outcome of each cue.

“When you’re under stress and ramped up, you’re not paying enough attention to what’s going on around. You’re just not changing or updating your response. You could argue that the kinds of stress we’re encountering in day-to-day life, psychological stresses, are more distracting. This is all honing in on the idea that when you’re under chronic stress or other stress, you just aren’t adapting as well. Exposure to social media and things…you could argue that you have access to changes of the world more frequently, so stress could change your ability to integrate changes of information and things going on around you,” Dr. Riao has told the Daily Mail online.

Interesting findings of the study

During the first day of testing, the research team observed a complete switch between the participants’ stress cues. According to their results, the respondents’ earlier threatening cue no longer predicted shock during the experiment. However, the formerly safe cue did stimulate shock among the participants, the scientists noticed.

The second day of testing also showed that participants in the stress group were less likely than the controls to change their responses to threats. According to the research team, the formerly safe visuals have already been perceived as shock-delivering images among the stress group. The findings demonstrate that stress has significantly impaired the stress group’s capacity to be flexible in responding to non-threats, the scientists have stated.

The research team also noted a marked reduction in a physiological response to threat among patients who have been stressed. According to the scientists, participants in the stress group exhibited learning deficit and a reduced attention signal. This indicates that experiencing stressful conditions may impair learning, the scientists have reported.

“Stress does not always increase perceptions of danger in the environment, as is often assumed. In fact, our study shows that when we are under stress, we pay less attention to changes in the environment, potentially putting us at increased risk for ignoring new sources of threat. As a result, stress can reduce the flexibility of our responses to threats by impairing how well we track and update predictions of potentially dangerous circumstances,” lead author Dr. Candace Raio has stated in a Futurity article.

Sources include:

Futurity.org

DailyMail.co.uk