The Science of FEAR

The “fear” response is almost entirely autonomic.  It begins with some outside stimulus and ends with what is commonly known as the “fight or flight” reaction.  Although the entire body is involved in the process, some parts play a central role, specifically the brain.  There are two paths taking place in the brain – the low road and the high road.  The low road is quick and messy while the high road takes more time to complete because it is a more thorough analysis of the perceived danger.  However, these two paths take place simultaneously.

The low road is based on a “take no chances” idea.  It is far less dangerous, according to the low road, to automatically assume something is dangerous.  Better safe than sorry.  The low road shoots first and asks questions later.  As soon as you perceive an outside stimulus, such as being startled by something, your brain sends that sensory information to the thalamus – the large mass of grey matter buried under the cerebral cortex involved in sensory perception and the regulation of motor functions.  The thalamus is not aware of the legitimacy of the perceived threat at this point.  To be safe, it forwards the information to the amygdala, a small almond-shaped mass of nuclei located deep within the temporal lobe.  The amygdala takes the necessary actions to protect you from the potential dangers, including telling the hypothalamus to initiate the fight-or-flight response to save your life.

The high road, as stated, takes more time because the process is more precise.  At the same time the brain is initiating the low road, it also initiates the high road to analyze the potential threat in more detail “just in case”.  Again, when you perceive a potential threat, the brain sends the signals to the thalamus.  In the high road, the thalamus sends this information to the sensory cortex, where the data is interpreted for meaning and applicability.  If it is determined that there is more than one possible interpretation, the information is then passed on to the hippocampus, which is the part of the brain responsible for memory functions, organizations, and storage.  It also connects emotions and senses to memories.   The hippocampus examines the information and compares it with past data in addition to picking up other clues and data that may have been overlooked by the low road process, such as branches tapping on a window.  Based on its analysis of this information, it will send its determination of “danger” or “no danger” to the amygdala and processes are carried out accordingly.  If there is no danger as determined by the hippocampus, it will “tell” the amygdala to “turn off” the fight-or-flight response.

Both paths are taking place at the same time.  This is why one will have a moment of terror before calming down, such as when we are startled by something.  Regardless of which road we are talking about, both paths ultimately lead to the hypothalamus.  About the size of a pearl, the hypothalamus plays an important role in the major functions of the body.  It is the control center for many of the autonomic functions of the peripheral nervous system, which consists of the brain, spinal cord, and a complex network of neurons.  It is responsible for sending, receiving, interpreting information from all parts of the body.  This portion of the brain controls our ancient survival reaction of the fight-or-flight response.

To produce this response, the hypothalamus must activate two different systems – the sympathetic and adrenal-cortical nervous system (SNS and ACNS).  Both are part of the autonomic nervous system (ANS), which regulates the functions of our internal organs, such as the heart, stomach, and intestines.  The combined effects of these two systems comprise the fight-or-flight response.  The overall effect involves speeding up the body, tensing up the muscles, and making the person become “very alert”.  The SNS sends out impulses to glands and muscles, which result in the release of epinephrine (adrenaline) and norepinephrine (noradrenaline) into the bloodstream.  These are also known as “stress hormones”, which cause several changes in the body.  Increased heart rate, increased blood pressure, and increased strength.  At the same time, the hypothalamus releases corticotropin-releasing factor (CRF) into the pituitary gland.  Located behind the bridge of the nose in the center of the skull, this gland is no bigger than the size of a pea and is an important link between the nervous system and hormones that effect many functions of the body, including metabolism.

Hormones, including adrenocorticotropic (ACTH), which move through the bloodstream and ultimately arrives at the adrenal cortex, where approximately 30 different hormones are released to get the body prepared to deal with the perceived threat of danger.

In the body, several reactions take place in addition to those mentioned.

  • Pupils will dilate to take in more light and receive more frames per second, allowing the person to absorbed as many details as possible;
  • Veins in the skin constrict to send more blood to major muscles, causing the “chills” commonly associated with fear, which is the result of less blood in the skin to keep it warm;
  • Blood-glucose levels increase;
  • Muscles tense up because they are energized by the adrenaline and glucose, which is the cause for the “goose bumps” when tiny muscles attached to individuals hairs tighten, force the hairs to stand upright, and pull the skin with them;
  • Some muscles relax to allow more oxygen into the lungs;
  • Nonessential systems are shut down, such as digestion and immune, to allow more energy for essential emergency functions; and
  •  A person may find it difficult to focus on small tasks because their brains are directed to focus only on the bigger picture to determine where the threat is coming from.

All of these reactions are our evolutionary response to being able to survive dangerous situations by either preparing you to run for your life and fight the threat.

There are two additional sides of fear not often mentioned – anticipation and conditioning.  Unfortunately, humans, unlike other animals, have developed a particular anticipation of events that might happen and, as a result, can inadvertently provoke these same responses even when there is no real threat of danger to the person.  Anticipating, also known as associating, a fearful stimulus can provoke the same responses as having actually experienced it.  It is important to remember, however, that what one person may view as a threat to them may not be viewed as a threat to another person.  For instance, one person may perceive spiders as a threat while another will not.  This is a result of what is referred to as conditioning.

Conditioning often occurs when someone has experienced something that leads them to anticipate a fearful stimulus.  For instance, if a child is bitten by a dog, they may become afraid of dogs as they get older because they associate dogs with a bad experience.  In another example involving dogs, this is often how they are trained.  For instance, if you associate a “punishment” with bad behavior, such as urinating on the floor, they are likely, in most cases, to stop the behavior.  They associate the “punishment” with the bad behavior.  In contrast, if you “reward” good behavior, such as giving them a treat when they sit, they will associate the “reward” with the good behavior.

Conditioning is a problem because your brain will automatically associate bad experiences with perceived danger.  For example, if a person has a scary perceived paranormal experience after going into a cemetery at night, they may become afraid to enter cemeteries at night, if at all.  They have become “conditioned”, meaning they have associated a bad experience with something conceivably “harmless”.  Any time they enter a cemetery, they may “anticipate” something bad to happen thus provoking the fight-or-flight response.

Be wary, however.  Just as conditioning can overemphasize the threat of danger, it can also under-emphasize or lead one to underestimate a real threat of danger.  For example, let’s say someone walks out onto a frozen lake during the coldest part of the winter in Canada and nothing happens.  Now, let’s say that same person walks out onto another frozen lake somewhere else.  Recalling their previous experience with a frozen lake, they might disregard the dangerous situation because of the previous experience, walking out onto the frozen lake only to discover it is much thinner and cannot hold their weight.  They fall through a crack in the ice, leading to hypothermia, frost bite, or even death.

The important thing to remember when investigating any location is to remain as calm as possible and not negatively anticipate, associate,  or condition yourself to possible activity.  This is essential in keeping an open-mind and not “psyching yourself out”, which could lead to false evidence and unreliable data.

Face it

Explore it

Accept it