Where fear comes from in the brain?

We come across a bear in the forest. To run away every breath or to stand motionless hoping that the bear will not notice us? The brain has to choose a strategy to deal with danger in a split second. Biologist Natalia Wroblewska talks about the study of the frightened brain.

We are walking through the forest and suddenly a big bear jumps out onto the path. One thing is certain – we will feel fear. Our blood pressure will increase and our heart rate will accelerate. But what else? SomeoSome will immediately start running away, while others are scared out of their wits "paralyzes", not allowing to twitch. – The same is true for a mouse. A mouse, when it perceives a threat, either starts running away or even "she is frozen by fear" (English. freezing). The latter strategy also makes sense: there is a chance that such a motionless mouse will not be noticed by the attacker, or he will think it is a carrion, an uninteresting target for attack. It is one of the innate abilities to respond to danger – mowi Natalia Wroblew, whichora is doing his doctorate at Cambridge University.

A Polish biologist works in a laboratory led by Tiago Branco of UCL. There he is studying how mozg makes a decision: whether to flee or freeze motionless in such a crisis situation. – It depends on many factorsoin – how close is the danger, how far is the hideoutowka whether we have had experience with dangerous animals, whether we are fast runners, whether we are tired and hungry. These decisions must be processed in a split second. Because and at such a time mozg makes a decision – he tells.

As part of his research on fear, the biologist checks m.In., how mice respond to skosnake hand. A piece of sk is put into the cageory, whichorą dropped snake – moult. – Although the mouse has never seen a snake because it was born in the lab, when it smells one, it feels fear and flees into a burrow, says a scientist. He explains that the strategy of standing still doesn’t make sense here – the threat is not visible.

Scientists in the roThe labs resort to rotrong ideaow in order to induce fear in mice under controlled conditions: the shadow of a predatory bird is moved over the cage, and at other times – into the cage a. wet cloth, whichorą earlier the cat has been wiped out.

– When a mouse smells the scent of a predator, neurons are activated one by one in the roof different regions: in the epithelium of the nose, in the amygdala of the mozgu, then in the hypothalamic partorza – they are the focus of my research – then in the medullaodmozgow, and then in the spinal cord. It is only these neurons that are responsible for muscle activation. It troubles us how information is processed at each of these stagesow,” says Natalia Wroblewska.

If threat information went straight from the nose to the muscles, the mouse would have no chance to integrate important information. – If there are cubs nearby, the mouse will probably not run away, but the sprob is to defend them. Its behavior will change inown completely – mowi conversationoPAP contributor.

– I like to look at neurons as calculators. They perform specific mathematical tasks. They add, subtract information, or even multiply it. Probu I understand how comorks process information thatorą get. And how do they help decide whoore behavior is the best in a given case – mowi biologist.

– We humans, although we may not be afraid of catow and birdow, then we have a similarly working network of connections in mozgu – mowi. Understanding how fear information works in mice brings us closer to understanding how it might work in healthy humans. And this is knowledge thatora will allow us to understand what is happening in the mozg malfunctioning – e.g. in mental illness.

Natalia Wroblewska explains that if we understand that e.g. comorki hypothalamusorza have to do with a sense of anxiety, perhaps someday in the future we will be able to use this knowledge. Np. Develop a drug thatory will affect the activity of these comorek and will reduce anxiety levels in people with anxiety disorders.

Sourceobackground: PAP – Science in Poland , Ludwika Tomala, fot. CC BY 2.0/ Flickr/ Neil Piddock