Fear as an emotion is universal; whether it be the fear of the dark, spiders, or heights. This intense, emotional reaction to a perceived threat infects the minds of many. It may seem more hindrance than help, however, for without fear we would all be reckless beings, putting our lives at risk. Not so great for the future of our species.
Fear is an evolutionary tactic that promotes survival; having innate fears that are passed onto our offspring allows the survival of future generations. Many of the fears we have today are likely to have been inherited from our hunter-gatherer ancestors. Our ancestors lived in an immediate return environment, whereby they would detect a threat and respond immediately. When hunting and being hunted was a common part of Homo sapien society, it is highly likely that we acquired our fear of predators along with tactics to avoid them. For example, fear of the dark has been said to stem from an evolutionary instinct that kicked in at night, when humans turned from top predators to prey. Predators would hunt at night and due to humans’ relatively poor eyesight in the dark, they were vulnerable to attack.Therefore our ancestors would ensure to stay hidden in the dark, when chances of being preyed upon increased.
Anxiety first emerged for human protection in the face of present danger. Fast forward to modern times, and our need to protect ourselves from predators has disappeared. Some of those instincts have remained ingrained in our programming, but most of our fear now lies in the future; whether that be paying bills on time, preparing for exams or working on a relationship. We now live in a delayed return environment, where the choices we make in the present will often not have an impact until later on.
The neuroscience behind fear has been investigated for decades. A ‘two systems’ framework has been proposed by the American neuroscientist, Joseph E. LeDoux. He presented that one system produces the conscious feeling of fear, while the other produces the subconscious physiological responses. The emotion of fear is generated by the cortical areas of the brain, including the hypothalamus. When we experience this fear, the sensory organs send signals to the amygdala, a key emotion processing unit within the brain. The amygdala activates arousal systems, such as the autonomic nervous system, as well as increasing stress hormone release. This stimulation prepares our body to make decisions about the potential threat and involves the stimulation of the sympathetic nervous system (a branch of the autonomic), also known as the fight or flight response. This process is all subconscious – we have no control over the physiological changes that occur, which include increased heart and breathing rate, pupil dilation and inhibition of digestion. These physiological changes prepare the body to either run from the situation, or stay and fight the threat. Pupil dilation increases visibility; digestion inhibition allows energy to be directed to more urgent sources; whilst increased heart rate and breathing rate enables oxygen and blood to be rapidly directed to tissues and muscles in need of it. All of these responses have evolved over time to what they are today.
Despite a lot of people wanting to avoid feeling scared, others crave it. People sit through horror movies, visit haunted houses and take part in extreme sports to feel the sensation of fear. This has been largely attributed to the release of dopamine, described as the feel-good neurotransmitter, during the fight or flight response causing a natural high.
Individual differences in brain biochemistry have been identified which allow us to understand why some people love the feeling of horror and others hate it. Some brains do not halt the production or reuptake of dopamine in the synapses, causing dopamine to remain in the synapses for longer and thereby prolonging the feeling of pleasure people experience during scary situations.
Other explanations include the knowledge of safety. Often the individual knows that they are safe and there is no real danger. They are triggering the fight or flight response, knowing that they are in a secure environment. On the contrary then, individuals who find these same situations petrifying could be due to these fears having been established during youth.
“Flashbulb memories” are strong memories formed from chemicals released during the fight or flight response; experiencing something scary at a young age before realising that it poses no real threat can lead to these fears being carried into adulthood in the form of flashbulb memories. A good example is the fear of monsters under the bed. When young, most children can’t understand that monsters aren’t real and so fear them intensely. They may be scared of the dark or going to sleep in case there are monsters under their bed. As they progress through adulthood, most will lose these fears. However, there are many adults who, despite knowing that monsters do not exist, will not sleep with their legs out of the cover in case of the bizarre chance that a monster grabs them.
American psychologist, Martin Zuckerman, discovered a specific personality trait which determines how much individuals enjoy fear-inducing activities. The trait is determined by 4 elements; susceptibility to boredom, spontaneity, desire for new experiences and thrill/adventure-seeking. After having carried out personality tests on participants, he found that individuals with higher scores enjoyed frightening experiences. These individuals also had lower levels of the stress hormones cortisol and adrenaline, and higher levels of dopamine. This confirms how these people seek more pleasure and less stress in these situations. Those who seek these thrilling experiences are more likely to work well in high-stress professions, such as A&E doctors, special forces etc. They are also more likely to respond better to our current delayed-response culture.
Those individuals who work well in high-stress environments, and release more dopamine than cortisol in response to stress, are likely to thrive in modern conditions. Conversely, those of us who are coined the ‘scaredy-cats’ or worriers are not as well adapted for survival in this culture. Chronic stress causes a myriad of mental health and cardiovascular-related problems; yet we are also very good at adapting to our environments and culture. Modifying our daily routines to reward ourselves instantaneously as well as in the future can have a great reduction in stress levels. In terms of human evolution, it is interesting to think how our fear responses to current threats could evolve and shape the way our descendants react to danger in the future.
Written by Millie Chambers and edited by Ailie McWhinnie.
Millie’s thoughts… The evolution of anxiety from an evolutionary tactic into a prolonged state of being is an area that fascinates me. Brains evolved in an immediate return environment, yet modern culture has thrust it into a delayed response environment, causing worry to be sustained for longer. Our bodies aren’t built to support these extended periods of stress and anxiety that modern society inevitably causes. I think we could all benefit from ensuring our daily routine involves both immediate rewards as well as formulating plans to work towards future problems.
Find her on Twitter @MillieChambers_.