Biology 202

2006 Second Web Paper

On Serendip

How can fear have such a strong hold on an individual? Fear can be seen as an emotion that can protect humans or animals from potential danger (1). Fear can also be seen as a feeling of uneasiness and hypervigilance. Experience and culture play a role in our feelings because they teach us what to fear in the world around us. Perhaps this is why people are disproportionately afraid of some things but can ignore others. Fear can be a healthy emotion because it keeps us on alert and watchful for possible threats. Death, I think is safe to say, is our most basic fear. I believe this because the fear of death functions to make us alert in dangerous situations. This idea definetly accounts for some fears but what about other fears that just have to do with being uneasy in certain settings or situations? What about fear of things that do not even cause a major threat to our lives?

Fear can be innate and/or acquired through experiences. Acquired or learned fear comes as a conditional reflex which is in response to two types of stimuli. One stimulus is usually neutral or harmless and that can be for example a bell ringing while, the other stimuli can be potentially harmful like an electric shock. If an animal is given a shock treatment immediately after the bell rings, it learns to associate the ringing of the bell with the shock treatment. From this observation, the animal will exhibit fearful behavior when it hears the sound of a bell ringing. From the two types of fear,
acquired fear can at many times manifest itself as an anxiety disorder or mental illness. So is there a neurological difference between the two types of fear?

What is happening in the brain when the feeling of fear arises? The emotion or feeling of fear in mammals, including humans, is processed in a pair of tissues located along the middle part of the brain, called amygdala. This processing occurs in the amygdala regardless of whether the fear is innate or conditioned. Studies by Dr. Gleb Shumyatsky and colleagues, according to India's national newspaper The Hindu , indicated that a gene known as GRP or gastrin releasing peptide, appears to inhibit the action of the circuitry in the amygdala that is linked with learned or conditioned fear reflex (1). So we know that the amgydala is the area where fear is turned on and processed but I wonder if there is a way to turn off fear. Just as fear can be triggered by a threat i.e. turned on, can fear be turned off? Is there a place in the brain that if it is triggered, it can completely remove a fear from a person's memory? I pose this question because it seems as if fear or most of fear comes from a memory
or an experience. If this is the case, can there be a way to totally erase the memory that causes the individuals fear towards an object or situation?

According Gregory Quirk of the Ponce School of Medicine in Puerto Rico, the medial prefrontal cortex (mPFC) suppresses the activity of fear-generating nerve cells in the amygdala and elsewhere in the brain (3). In the September 24, 2003 Journal of Neuroscience, the researchers reported that electrically stimulating the mPFC reduces the responsiveness and activity of nerve cells in the amygdala's central nucleus. According to Quirk, the fearful memory is still stored in the brain, perhaps elsewhere in the amygdala, but the mPFC actually prevents the memory from generating fear or anxiety (3). Researchers are investigating whether they can extinguish fear in people by directly stimulating the mPFC. I am pretty sure though that stimulating the mPFC would not include shooting lasers or things of the such into the brain, it would probably be carried out through pharmaceutical drugs or by another less invasive treatment. I am a little skeptical about this idea because fear seems to be such a strong emotion that it does not seem like just the stimulation of mPFC alone would erase all a person's memory of fears that they have. I think the investigation of mPFC is still worth doing though.

The idea of shutting off fear seems to be valid because the purpose of fear is to warn or keep us from future discomfort yet we experience fear itself in an uncomfortable state. I guess the overall goal with Quirk's study, is trying to help individuals feel comfortable while still avoiding possible threats or situations that could cause future discomfort. From what I understand, when we experience fear we are in a state of caution from a possible threat. Some people could argue that fear is always based on something that has not happened yet, and is therefore a fantasy of our mind rather than fact. However, if someone knows that lions like meat, is it not reality (and not fantasy) that if I sleep next to a lion in the zoo, 9 times out of 10 I will not wake up with all of my body parts? In fact I may not even wake up...why? I WOULD BE DEAD! Just because it has not happened yet, does not mean that it is just part of my imagination. What we know to be true or factual is from what we have learned in life experiences
and from our culture or from tv shows like "When Animals Attack". People who have not had experiences with certain animals but are still afraid of the animals, are sometimes seen as irrational or abnormal. Why?

What classifies an individual as abnormal or normal when it comes to fear and disorders like phobias? What I find to be a bit unsettling is the fact that I to some may seem to be abnormal because I have a phobia of cats. However, what level must be reached to qualify me as an abnormal individual simply because what seems to scare me does not scare others. Where is the line drawn between normal fears and abnormal or irrational fears? I feel at times people with irrational fears as with phobias, are immediately shut down by others because their fears are not rational, but where is the line between realistic and non realistic fear. According to Dr. Jeffy Ricker, a fearful individual may be classified as abnormal if their fear is more severe than is warranted by the actual threat and/or if the individual's behavioral response to the fear is severely maladaptive (2). I concur with Dr. Jeffy to some extent with his beliefs because some fears of like fish or heights may not seem to be rational because those things are not fatal. However, the question still remains of how exactly you determine what fear is more severe than is warranted? Is it just based on what the majority of people feel towards the animal or situation?

Fear is a tough subject to tackle with because it seems to be all relative to one's own experiences. At the same time though, it seems like there is a clear difference between what I think poses a threat to a person versus what another person might think poses a threat to them. Since there is this difference I do not think it is fare to minimize someone else's fear simply because it does not fit in the category of accepted fears. Innate fear and acquired fear does not even help in the distinction of what is normal and what is abnormal because then you would be making a nature versus nurture argument. I think that fear plays a very important role in how we live our lives because it can definitely protect us from certain situations but it can really hold us back from situations where there really is no threat. I think that is where the idea of nothing to fear but fear itself, comes in.

Bibliography

1) http://www.hindu.com/seta/2005/12/15/stories/2005121500071600.htm. The Hindu: India's National Newspaper. 2005.
2) Dr. Jeffy Ricker. http://www.sc.maricopa.edu/sbscience/psy266/course/fear-anxiety.html. Fear and Anxiety.
3) John Travis. http://www.sciencenews.org/articles/20040117/bob9.asp. Science News: Fear Not.


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