The Chemistry of Fear!

Dan Wiggins

by Dan Wiggins

20th August 2015

Most of us enjoy watching horror films, going through the haunted house at the theme park & watching creepy videos online at 2am… but why? We voluntarily choose to be put in these situations at times in order obtain the motion of fear, it’s natural that we enjoy the stimulation produced when we are scared, but what makes us want to watch the scary videos, horror films, and other things?

The Brains Sensitivity to Threat

The brain is highly sensitive to any indication of threat, and when we are placed in a situation where our body and mind detect danger, various chemicals are released from our brain to prepare us to either engage with the dangerous threat, or to flee from the situation. This is better known as ‘Fight or Flight’ and is a way of describing the conscious choice we make when we are presented with a dangerous threat that could cause us harm. Whether it be stress from work, an angry person at bar who’s beer you knocked over, or an argument with your partner. Since the beginning of human existence, the idea of fight or flight has existed, and our minds awareness of this decision has not altered. Even if our situation since then has slightly altered, to say the least!

“Fear is the expectation or the anticipation of possible harm … We know that the body is highly sensitive to the possibility of threat, so there are multiple pathways that bring that fear information into the brain”

Abigail Marsh, associate professor of psychology at Georgetown University.

The Chemistry behind Fear

When we are placed into a dangerous situation that we deem harmful, a signal is sent to the thalamus which is a central station in the middle of your brain. The signal is then relayed directly to the amygdala. The amygdala is an extremely critical component in our response to fear as this is what releases various neurotransmitters into the body. There are multiple neurotransmitters released into the body, but when it comes to fear, the most important neuron is glutamate. From this, a cascade of other responses are triggered, such as the information from the glutamate that is sent to an area of the brain called periaqueductal gray. This area is directly responsible for behavior we expel when we are frightened, such as jumping, shouting, and freezing.

Aswell as this, the information is also sent to an area of the brain called the hypothalamus, which is responsible for the autonomic nervous system. This controls reactions that we relate to fear, such as increased heart rate and high blood pressure aswell as heavy breathing. The signals from the hypothalamus are sent down into the body into the adrenal glands which emit cortisol and adrenaline. We all know that adrenaline is often explained as a chemical relased into the body when under pressure, in order to help us make quick decisions to determine our survivabiltiy.

Do We Enjoy Fear?

It may not sound all too crazy if you think of fear as a pleasurable factor for the mind and body. Especially, when you consider dare-devils, adrenaline junkies  and thrill seekers risking their lives to get an ‘adrenaline rush’, they encounter fear, but they use it to their advantage and harness the adrenaline produced from their body into enhancing their minds to complete the task. Much to the same when we watch a scary movie, even though we are just spectating a situation, our brains still receive the information and process it as a dangerous encounter, releasing the chemicals into our brains preparing us for the fight or flight scenario. Dopemine is released when we are scared, which is often related to as the brains ‘reward’ system and is released in response to pleasurable things. So does that mean that we enjoy frightful situations?

This excellent video from internet celebrity and mountain bike enthusiast Danny MacAskill explores how adrenaline seekers from across the world obtain their adrenaline fix and the brain systems explored between those who seek adrenaline rushes, and those who prefer to remain out of harms way.

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