Researchers from the University of Cambridge and University College London have found that a neurochemical known as noradrenaline helps us learn quickly and adapt to uncertain situations.
"Adapting to uncertain situations helps us to survive. When something unexpected happens, we have to decide whether it's a one-off and ignore it, or whether it's going to keep happening—in which case we might benefit by doing things differently," says Dr. Rebecca Lawson, lead author of the study.
For the study, the researchers recruited 40 people, none of whom had an anxiety disorder. While some participants were given Propranolol, a drug used to reduce anxiety and blood pressure that also blocks noradrenaline, others were given a placebo.
During the experiment, the researchers then taught the participants to associate an image of either a house or a face to a certain sound. They then changed the images following the sound at random intervals to increase uncertainty and make it necessary for the participants to learn new associations.
In the end, the researchers found that participants who received the placebo tended to have slower reaction times as associations became more unexpected, showing that they were tuning into their environments more. On the other hand, those who received Propranolol tended to rely on the sound to a larger extent during uncertain times, showing they were more reliant on their past experiences.
To delve deeper into their observations, the researchers used a computational model that indicated that those on Propranolol were slower than the placebo group at learning new information and adjusting their expectations during uncertain situations.
"In the face of uncertainty, people taking the anti-anxiety drug Propranolol showed an increased reliance on past experience to inform their behavior—they were less influenced by changes in their environment that contradicted that experience," says Dr. Rebecca Lawson, lead author of the study.
The researchers now aim to extend their research to understand how people with these conditions learn in times of uncertainty. In the long term, they hope their findings will be able to help those with anxiety recognize the sources of their symptoms and better manage them.