Be Afraid, Be Very Afraid: A Halloween Special


It’s dark. You’re out at night. You’re on your own. Walking down a dark isolated alley, you know this shortcut is risky – but it is the only way to get home. Then suddenly two figures appear at the end of the alley, blocking your exit. That horrible gut wrenching, panicky feeling shudders, lurches through your body. “Trick or Treat!!” they yell.

Of course, it’s Halloween and the two hooded figures turn out to be two kids dressed as the grim reaper laughing in hysterics as they skip off down the street.

What happened to cause this reaction? What is fear? Well according to the dictionary, the simple answer is that it is: An unpleasant emotion caused by the belief that someone or something is dangerous, likely to cause pain, or a threat. But as you probably guessed it’s a lot more complex than that.




How does it work?
There are two reactions to fear. After a stimulus for example a spider, your brain will take to paths called the high road and the low road.

So firstly, the low road, this is an immediate reaction, which will come before properly thinking about the stimulus. Which is why, in some cases, you jump when your brother jumps out from behind the sofa. But when you realise who it is, this intense panic and fear disappear as soon as it came (unless he is a wanted serial killer who has a grudge against you...) so as soon as you see the stimulus, this sensory information is sent straight to the thalamus, which is forwarded straight to the amygdala. Because through evolution we have needed this animal instinct to survive and we need to be able to react instantly to danger. This then tells your hypothalamus to initiate a fight or flight reaction which I will come onto later in this blog.

So at the same time as this, the high road reaction is being carried out. This reaction takes a bit longer as your brain processes whether this is a real threat. This time the sensory information is sent from the thalamus to the sensory cortex where it determines whether there could be other reasons or meanings to this stimulus. For example if the people at the end of the dark alley were axe murderers or indeed harmless children. This is then sent along to the hippocampus to establish the context of the situation, and by taking into account previous experiences and other external surroundings, it decides whether there is danger or not. This information is then sent to the amygdala, and in the case of the dark alley, tells the hypothalamus to shut off the fight or flight mechanism.


Fight or flight?
This is our body's primitive, animal reaction which prepares us to 'fight' or 'flee' from any predators. I know in this day and age there is hardly going to be a tiger hiding round the corner, but this response is still essential.

There are two systems activated by the hypothalamus - the sympathetic nervous system and the adrenal cortical system. The sympathetic nervous system stimulates nervous reactions in the body and it causes tightening of the muscles, to prepare you for running or fighting, also in general your body speeds up and becomes very alert. Your eyesight sharpens with your pupils becoming dilated to let more light in. This stimulates two hormones to be released into your bloodstream which raise your blood pressure and heart rate; these are called epinephrine (adrenaline) and norepinephrine (noradrenaline). At the same time around 30 other hormones are secreted from your adrenal cortical system. This also causes blood to be shunted away from your digestive tract and directed into your muscles and limbs, which require extra energy and fuel for running and fighting. This extra energy is also responsible for goose bumps - when tiny muscles attached to each hair on surface of skin tense up, the hairs are forced upright, pulling skin with them. Also, that 'chill' you experience when faced with danger is caused by your viens in the skin to constrict more, allowing more blood to major muscle groups.

Another huge benefit of this response is that our perception of pain decreases.At times when our actual physical survival is threatened, there is no greater response to have on our side. When activated, the fight or flight response causes a surge of adrenaline and other stress hormones to pump through our body. This surge is the force responsible for a sometimes sudden super human strength and courage, like mothers lifting cars off their trapped children and for firemen heroically running into blazing houses.


Why do we fear certain things?
Why are some people so scared of dogs when some treat them like one of the family? This is because of conditioning. In the 1920s, American psychologist John Watson taught an infant to fear white rats. Before the experiment, "Little Albert" was not scared at all of the little white rats. He wanted to play with them and hold them; however Watson and his assistant taught Albert to be terrified of white rats. They used Pavlovian (classical) conditioning, pairing a neutral stimulus (the rat) with a negative effect. Whenever Albert reached for one of the rats, they created a terrifyingly loud noise right behind the 11-month-old child. Not only did Albert very quickly learn to fear the white rats, crying and moving away whenever he saw one, but he also started to cry in the presence of other furry animals and Santa clause mask with a white beard.

Phobias
Like Little Albert's fear of white rats, a person's fear of dogs is most likely a conditioned response. Perhaps he was bitten by a dog when he was three years old. Twenty years later, the person's brain (the amygdala in particular) still associates the sight of a dog with the pain of a bite.
Here are the top 10 phobias held by the people of Britain today:

Top Ten Phobia List:
1. Arachnophobia - fear of Spiders
2. Social Phobia - fear misjudged in social situations
3. Aerophobia - fear of flying
4. Agoraphobia - fear of a situation where there is no escape
5. Claustrophobia - fear of enclosed spaces
6. Acrophobia - fear of heights
7. Emetophobia - fear of vomit
8. Carcinopobia - fear of cancer
9. Brontophobia - fear of thunder and lightning
10. Necrophobia - fear of death

How can you overcome fear?
Fear extinction involves creating a response that counters the fear response. Like in the example of Little Albert above, fear memories formed by conditioning are usually stored in the amygdala, however fear-extinction memories form in the amygdala but then are transferred to the medial prefrontal cortex for storage. This creates a new memory of fear extinction which constantly attempts to override the fear memory triggered in the amygdala.

Most behavioral therapies for fear extinction focus on exposure. For example gradually introducing yourself to your fear, talking about it, doing it. If your fear is spiders, gradually seeing them closer and closer or seeing pictures of them. And when they realise nothing bad happens this forms the new positive fear extinction memories in their medial prefrontal cortex. So the fear still exists in the amygdala, but the idea is to override it with the new memory.

Bibliography:
http://science.howstuffworks.com/environmental/life/human-biology/fear4.htm
http://www.nativeremedies.com/ailment/overcoming-fears-info.html
http://www.thebodysoulconnection.com/EducationCenter/fight.html

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