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It is a fundamental, deeply wired reaction, evolved over the history of biology, to protect organisms against perceived threat to their integrity or existence. Fear may be as simple as a cringe of an antenna in a snail that is touched, or as complex as existential anxiety in a human.
So, it makes sense that the high arousal state we experience during a scare may also be experienced in a more positive light.
We are psychiatrists who treat fear and study its neurobiology. But how does your brain do this? This almond-shaped set of nuclei in the temporal lobe of the brain is dedicated to detecting the emotional salience of the stimuli — how much something stands out to us.
For example, the amygdala activates whenever we see a human face with an emotion. This reaction is more pronounced with anger and fear. A threat stimulus, such as the sight of a predator, triggers a fear response in the amygdala, which activates areas involved in preparation for motor functions involved in fight or flight.
It also triggers release of stress hormones and sympathetic nervous system.
Heart rate and blood pressure rise. Blood flow and stream of glucose to the skeletal muscles increase. Organs not vital in survival such as the gastrointestinal system slow down.
They were spoken by British gerontologist Aubrey de Grey. Ageing follows the same principle.
A part of the brain called the hippocampus is closely connected with the amygdala. The hippocampus and prefrontal cortex help the brain interpret the perceived threat.
They are involved in a higher-level processing of context, which helps a person know whether a perceived threat is real. For instance, seeing a lion in the wild can trigger a strong fear reaction, but the response to a view of the same lion at a zoo is more of curiosity and thinking that the lion is cute.
This is because the hippocampus and the frontal cortex process contextual information, and inhibitory pathways dampen the amygdala fear response and its downstream results.
If a sign says the dog is dangerous, proximity to the dog will trigger a fear response. We learn safety in a similar fashion: experiencing a domesticated dog, observing other people safely interact with that dog or reading a sign that the dog is friendly.
When something scary happens, in that moment, we are on high alert and not preoccupied with other things that might be on our mind getting in trouble at work, worrying about a big test the next day , which brings us to the here and now.
Furthermore, when we experience these frightening things with the people in our lives, we often find that emotions can be contagious in a positive way.
We are social creatures, able to learn from one another. While each of these factors - context, distraction, social learning - have potential to influence the way we experience fear, a common theme that connects all of them is our sense of control.
That perception of control is vital to how we experience and respond to fear. It is important to keep in mind that everyone is different, with a unique sense of what we find scary or enjoyable.
This raises yet another question: While many can enjoy a good fright, why might others downright hate it? On the other hand, if the experience is not triggering enough to the emotional brain, or if is too unreal to the thinking cognitive brain, the experience can end up feeling boring.
So if the emotional brain is too terrified and the cognitive brain helpless, or if the emotional brain is bored and the cognitive brain is too suppressing, scary movies and experiences may not be as fun.
Disorders of anxiety and fear include phobias, social phobia, generalized anxiety disorder, separation anxiety, PTSD and obsessive compulsive disorder.
The good news is that we have effective treatments that work in a relatively short time period, in the form of psychotherapy and medications.
This article was originally published on The Conversation.