New research provides evidence that anxiety influences escape decisions in threats that develop slowly — but does not impact threats that require an immediate response. The findings appear in the journal Nature Human Behaviour.
“I think that almost all people are affected by anxiety at times. The typical scenarios that make people anxious (public speaking or performance, etc) must have some commonalities between them, and it’s a curiosity why (evolutionarily speaking) we would get anxious at all if it negatively affects us,” said study author Bowen J. Fung (@bowenjfung), a postdoctoral scholar in the Division of the Humanities and Social Sciences at the California Institute of Technology.
“Although these questions are far from answered, in this study we’ve tried to address both: looking at some (specific) factors that differentially cause anxiety, and using an ecological, semi-realistic paradigm that might inform why anxiety can be beneficial.”
In the study, 28 participants played a “virtual predator” video game while inside a functional magnetic resonance imaging machine that measures brain activity. The participants’ goal was to escape attack from the virtual predator.
The longer they waited out an impending attack, the more money they earned. But if they waited too long and were caught, they received an electrical shock to the hand.
The researchers found that participants who scored higher on a measure of anxiety were more likely to escape from “slow attack” predators that approached for a longer time before attacking. Anxiety, however, was unrelated to escape decisions for “fast attack” predators that quickly switched from slowly approaching to attacking.
“Not all negative circumstances can lead to feelings of anxiousness. This may be obvious to some people, but had not been rigorously tested,” Fung told PsyPost.
“In particular, a subtle difference like the proximity of a threat shows that we can be more specific about how anxiety arises. Similarly, we show that anxiety can have positive effects — in our case leading to more successful escapes from virtual predators.”
Previous research has indicated that the “slow attack” and “fast attack” predators were associated with different brain responses.
The fast threats led to reactions in the fear circuit, located in the central part of the brain, which consists of connections between two structures known as the periaqueductal gray and the midcingulate cortex.
The slow threats, in contrast, led to heightened brain activity in the hippocampus, the posterior cingulate cortex and the ventromedial prefrontal cortex — areas of the brain associated with memory, planning, and assessing risk.
In their new study, the researchers found that higher anxiety was associated with stronger functional coupling between two areas of this brain circuit — the hippocampus and prefrontal cortex.
“In our study we found that the proximity of threat changes can affect the anxious response, but the threats were also different in the amount of time they allowed for responses. So we don’t know exactly whether the delay or the distance of threat is responsible for changes in anxiety,” Fung said.
“On the other hand, it is quite difficult to imagine a natural scenario where the delay and distance of a threat are not highly correlated. Another we don’t yet know is exactly how close or how far a threat needs to be to cause anxiety. Most probably this will vary on a person-to-person basis, which may be a useful way to characterise differences in anxiety disorders.”
The study, “Slow escape decisions are swayed by trait anxiety“, was authored by Bowen J. Fung, Song Qi, Demis Hassabis, Nathaniel Daw, and Dean Mobbs.