Three brain chemicals affect how we handle uncertainty
New research has revealed how three important brain signaling chemicals affect the way that we handle uncertainty.
It turns out that noradrenaline regulates our estimates of how unstable the environment is, acetylcholine helps us adapt to changing environments, and dopamine pushes us to act on our beliefs about uncertainty.
The research, published in PLOS Biology, was led by Louise Marshall and Dr. Sven Bestmann at the University College London (UCL) Institute of Neurology.
The study involved 128 healthy participants who took part in a reaction-time task designed to test how they handled uncertainty. Participants were all given either a placebo or a drug to block noradrenaline, acetylcholine or dopamine before starting the task.
Participants responded to symbols that were presented one after the other by pressing a corresponding button. The probability of each symbol appearing was dependent on the symbol that appeared previously; for example, if a participant had just seen symbol A, there was an 85% chance that symbol B would appear next. Every 50 trials, these probability patterns changed without warning, so participants had to detect these new patterns and adjust their responses accordingly.
Lead author Louise Marshall said: "Interacting with our dynamic and ever-changing environment requires us to frequently update our beliefs about the world. By learning the relationships that link events occurring in our environment, we can predict future events, and execute fast, accurate responses. However, the environment's complex dynamics give rise to uncertainty about the relationships between events, and uncertainty about the stability of these relationships over time."
She continued: "Several brain chemicals have been proposed to modulate how we handle uncertainty. Here we combined pharmacological interventions and novel computational models to determine how noradrenaline, acetylcholine and dopamine enable our brains to learn the changing relationships in our environment. The results shed important light on how humans learn to behave under uncertainty."
Note: Material may have been edited for length and content. For further information, please contact the cited source.
Marshall L et al. Pharmacological Fingerprints of Contextual Uncertainty. PLoS Biology, Published November 15 2016. doi: 10.1371/journal.pbio.1002575
We make judgements quite rationally or "by the gut". Not only experience and relevant information play an important role, but also our preferences. A study by the Max Planck Institute for Metabolism Research in Cologne shows how the reward system in the brain conveys judgements affected by one's own desires, and how our inner beliefs are altered more by good than bad news.
The emerging technology of sonogenetics—a technique where cells are controlled by sound—offers the potential to one day replace pharmaceutical drugs or invasive surgical treatments for neurological conditions like epilepsy, Parkinson’s disease or post-traumatic stress disorder. A new research program could take this technique to the next level with $750,000 of funding.READ MORE
5th International Congress on Epigenetics & Chromatin
Aug 22 - Aug 23, 2019
International Conference on e-Health and Healthcare Innovations
May 08 - May 09, 2019