What is the brain’s reaction to sudden events?

According to a new study, when your brain needs attention to something important, one way to do so is to send out a norepinephrine supplement.

The study, led by scientists from the Massachusetts Institute of Technology and published in the journal Nature, found that the hormone noradrenaline, also known as norepinephrine, which acts as a neurotransmitter, is released when we need to focus or pay. of attention to something. important.

And while it does this deep in the brain in a structure called the locus coeruleus, it can help encourage beneficial behavior. In other words, it plays a role in learning behaviors through trial and error and rewarding.

In a recent study on reinforcement learning, scientists tested this phenomenon in rats.

The team trained the rats to press a lever when they heard a high-frequency tone but not a low-frequency tone. A reward (water) was given when the rats performed correctly, but an unpleasant blast of air was given when they made a wrong move.

Over the course of the experiment, the rats also learned to push harder and harder, which caused them to become disoriented when the sound was quiet.

To test their theory of noradrenaline, they suppressed the hormone-regulating “blue locus,” which caused the rats to hesitate to push the lever when they heard low-pitched sounds.

Scientists have hypothesized that the hormone makes them more likely to take risks to receive a reward, even if they are not sure if they will receive the reward.

In other words, scientists believe that the structure in the brain suggests that rats will be rewarded if the lever is pressed.

The author of the senior study Professor Marijanka Sur, Newton Professor of Neuroscience in MIT’s Department of Brain and Cognition, is a member of MIT’s Beckware Institute for Learning and Memory and says, “An animal pays because it asks for a reward and offers a position. ” Strong blue are important signals to say: Pay now, because the reward is coming, the Simmons Center for the Social Brain told SWNN.

Through experimentation, the scientists discovered that neurons that produce noradrenaline induce behavioral functions by sending most of their production to the motor cortex. Then comes the second surge of adrenaline after pushing the lever.

While the scientists expected the secondary output of the hormones to be smaller, they were surprised that it was actually larger.

They also found that it spreads to other parts of the brain, not just to one part of the brain, including the prefrontal cortex, which controls planning and other thought functions.

“What this study shows is that the locus coeruleus encodes unexpected events, and attention to these sudden events is critical for the brain to assess its environment,” Sohr said.

Thus, the animal “constantly adjusts its behavior”, even though it has learned what it is doing.

In subsequent experiments, the scientists discovered that rats were more reluctant to push a lever when a reward was not promised.

“Neuromodulators are thought to irrigate large parts of the brain, and thus alter more of the excitatory or inhibitory impulse received by neurons from point to point. . Regulation of life and state of the brain ”.

However, noradrenaline is not the only hormone that affects brain activity as a neurotransmitter. There is also dopamine, serotonin and acetylcholine, which have a more general effect because they affect large parts of the brain.

While many studies have been done on the role of dopamine in the brain, especially when it comes to motivation and reward, noradrenaline has not been studied. The hormone is associated with both wakefulness and wakefulness, but overload can cause anxiety.

Sohr said: “It looks like the blue locus spike coding function is more common in the brain, and that might make sense because everything we do changes in surprising ways.”

Source: The New York Post