We call fear the feeling of anguish we experience when faced with a situation of danger or threat, real or imagined. The fear in the brain is the result of the activation of an adaptive alarm system in the face of danger, which triggers physiological, behavioral and cognitive aimed at survival.
Neuroscience research has always linked fear to a brain structure called the amygdala. This is located in the limbic system and plays a decisive role in the search and recognition of danger signals, as well as being linked to other emotions. Usually the amygdala is inactive, but activates in case of a threat.
More recently, fear has been found to activate other structures and networks within our brains which, together, prepare our bodies for the threat. A recent meta-analysis found that the amygdala is not the main fear-related area in the brain. Let’s find out more!
Learning of fear
Even if fear arises naturally, humans learn most of their fears. This phenomenon is called fear conditioning and can occur intentionally.
This Pavlovian-type learning is generated by the coupling of a neutral stimulus (for example square) and a hostile stimulus (for example a loud noise).
The neutral stimulus, which initially did not provoke any reaction, ends up causing a conditioned response, in this case that of covering the ears.
Fear learning appears in disorders in which the person initially felt no negative feelings in response to an event. For example, a person who quietly took public transport, but who after a few panic attacks and the consequent feeling of dying, is terrified of taking a bus again.
Fear in the brain and areas involved
Fear in the brain activates the brain areas summarized below: insular cortex, anterior dorsal cingulate cortex and dorsolateral prefrontal cortex.
- Insular cortex: found on both sides of the brain. It is a region that integrates cognitive and physiological information and is linked to the formulation of predictions about what may happen. It is also charged with integrating emotions from the amygdala and the senses, resulting in threatening interpretations. Finally, it is linked to aversive conditioning, that is, the anticipation of consequences.
- Anterior dorsal cingulate cortex : plays a vital role in fear learning and avoidance conduct, as well as in the subjective experience of anxiety. It acts as a mediator in conflict situations, determining the importance of stimuli, directing our attention and bringing rationality. The more active it is, the more we are able to pay attention. and therefore the greater the fear.
- Prefrontal cortex: the dorsolateral region is responsible for the emotional regulation of fear and the expression of relative physiological responses. On the other hand, the ventromedial region makes it possible to distinguish threatening stimuli from safe ones.
The expression of fear in behavior
When we feel fear, our brain responds quickly and involuntarily. It sets in motion a complex network that powers our body to escape from this situation.
As a result of the activity of insulin, we begin to sweat, our heartbeats accelerate preparing to escape, and our legs are activated. It therefore triggers the physiological responses to prepare our body to run. The anterior cingulate cortex focuses our attention on danger, activating the cognitive mechanisms necessary to deal with the situation (for example, choosing whether to ask for help or run). Simply put, the brain allows us to survive.
However, if the flight response or thoughts are excessive, a maladaptive behavior pattern can be produced as previously mentioned. For example, when we can’t get out of the house anymore.
In these cases, it is the insula that interprets as threatening a stimulus that in reality is not, or the cingulate cortex that makes us concentrate on neutral stimuli; just as we tend to escape or avoid a non-threatening stimulus under the influence of the prefrontal cortex. In other words, the damage is visualized in advance in a harmless situation, transforming fear into pathology.