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Living With Fear

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Caitlin Jeschke's picture

       Everyone that has experienced fear at some point during his or her life knows how strongly this sensation can influence one’s actions, for better or for worse.  Automatic fear responses (i.e. the “flight” portion of the “fight or flight” response in the sympathetic nervous system (2)) can be helpful when we are faced with potentially dangerous situations, because they allow us to react quickly, and in ways that are designed to prevent harm.  On the other hand, there are some types of fear (anxieties) that are seemingly unfounded, and which can be counterproductive, interfering with our everyday lives.  With anxiety disorders affecting about 18 percent of American adults each year (4), recent studies have focused on finding the biological basis for fear or the neurological pathway for its associated emotional response, in order to facilitate treatment for such disorders.  However, it is known that fear is not merely an automatic physical reaction—there is often a great deal of conscious processing that determines how a person will behave in response to a particular stimulus.  And, because emotions such as fear have a large cultural component, responses differ greatly from society to society as well as from individual to individual (7).  Will chemical therapy alone ever be enough to treat all individuals suffering from excessive anxieties?  And, finally, do all cases of anxiety in fact warrant treatment?  Since our nervous systems are capable of detecting and responding to signals that we are not consciously aware of (3), how do we really know whether or not feelings of discomfort or fear are unfounded? When is it safe to ignore such feelings, and when should we act on them? 

       When we experience something “frightening,” such as hearing a loud noise behind us, or seeing a dangerous animal, there are certain physiological responses that occur involuntarily, via the autonomic nervous system.  For example, blood is sent to the limb muscles to prepare for movement, heart rate increases, and we may move our hands in order to protect our eyes or head.  These responses are associated with rising levels of adrenaline in the body (2).  After this initial response, we analyze the situation in order to assess the level of danger.  Sometimes, we take further action to ensure our safety.  Often, however, we determine that there is no cause for alarm, and are able to override the “flight” response and resume normal activities.  It is evident, then, that a person’s conscious thought plays an important role in determining behavior.  How might the “I-function” exert this control over the autonomic nervous system?  Scientists are very interested in the neurological pathways that could allow such an intervention to occur.

       One interesting study at Colombia University Medical Center suggests that an “emotional control circuit” acting via the rostral anterior cingulate cortex may be what allows patients to sense fear but then decide whether or not to respond to it (1).  In this study, patients were presented with a series of photos depicting facial expressions.  Each photo was accompanied by a word (either “fear” or “happy”) that either did or did not correspond to the emotion that the photo illustrated.  The patients were then asked to identify the emotion that went along with each facial expression.  When the words and pictures were not in sync, the patients experienced activity (measured via fMRI) in the amygdala, thought to indicate the signaling of emotional discomfort or conflict (1).  This conflict interfered with the patients’ ability to answer the question, causing a delay in response and a higher frequency of incorrect answers.  The patients apparently overcame this conflict using the rostral cingulate cortex; activity in this area of the brain weakened the signal from the amygdala, allowing the patients to properly analyze the photo.  This demonstration of emotional control indicates that at least two processes (the amygdala’s signaling upon sensing danger and the rostral cingulate cortex’s ability to dampen this original signal) need to be considered when analyzing abnormal fear responses (1).  But what exactly constitutes an abnormal response? How do we decide, for example, when it is appropriate to dampen warning signals from the amygdala? 

       The nervous system keeps track of the body (ex: position, temperature, chemical levels) via proprioception and corollary discharge signals.  These signals provide constant communication between various parts of an organism, and allow the nervous system to make any changes necessary in order to maintain optimal conditions.  When the nervous system receives conflicting signals (ex: sensory information that does not match up to corollary discharge signals), feelings of pain or discomfort may result (8).  This discomfort, in effect, tells the body that something is wrong, and that action should be taken to resolve the conflict.  An example of this phenomenon is phantom limb pain, in which a person who has had a limb amputated feels pain in that limb (5).  One probable cause of this pain is that the nervous system is receiving corollary discharge signals about the position of the limb from nearby body parts, but (obviously) is receiving no sensory input from the limb itself (8).

       People experiencing serious pain are unlikely to ignore it, or to try to convince themselves that it is insignificant.  Why, then, do we so often try to ignore feelings of anxiety, when they lead to similar physiological discomfort, and could very well be indicating that something is indeed wrong?  The answer may lie in the fact that our behavioral responses to emotional experiences are very much influenced by the culture in which we are raised.  We are, to a certain extent, taught what to fear and what not to fear.  For example, women in western societies have traditionally been taught to be more open with their emotions, and more fearful in general. Men, on the other hand, have been taught to keep emotions, especially fear and sadness, to themselves, and to demonstrate more aggressive, angry behaviors (7).  The resulting beliefs as to what constitutes normal behavior could be very influential for an individual in terms of how he or she will react to a stimulus.  Such behavioral norms vary not only across gender lines but across cultural ones as well (7).  Without delving further into the topic of culturally-constructed roles, suffice it to say that, since conscious thought is known to mediate behavior, responses to fear are likely to vary greatly among individuals.  Thus, some people may choose to downplay the severity of their concerns.  As such, I think that any experimental results claiming to correlate measured physiological responses with reported emotional responses need to be taken with caution, because it is impossible to get a quantitative, objective description of an emotional response. 

       There are some definite benefits to being afraid in certain situations (ex: when one encounters a ferocious animal, or senses a fire).  It is also useful to be able to think through hypothetical scenarios, and to thus become aware of possible future dangers, even when there is no immediate threat.  This foresight enables us to make smart and safe decisions, and can be thought of as a way for our “I-functions” to protect us from future harm. One might even argue that becoming nervous as an assignment deadline approaches increases productivity, and is thus beneficial.  However, at some point, fearing intangible or nonexistent situations can interfere with daily function.  This brings us to the topic of anxiety disorders.  When does fear become excessive?  What are some of the effects that excess anxiety has on a person’s life?  How does the person attempt to deal with this anxiety?  And how successful are these attempts? 

       Anxiety is described as an emotion that, unlike most fear, is either unable to be attributed to a tangible cause, or is unnecessarily severe and out or proportion to any actual threat involved (2).  Some common anxiety disorders include panic attacks, obsessive-compulsive disorder, post-traumatic stress disorder, social anxiety disorder, and phobias (4).  It has been suggested that, since the nervous system is known to be plastic and therefore somewhat trainable, some anxieties (particularly phobias) may be attributable to a traumatic event from an individual’s childhood, inducing a fear response upon exposure to a particular stimulus (2).  However, what if there is no discernable cause for the anxiety? 

       One disorder that is very interesting both for its symptoms and for its associated attempts at self-treatment is obsessive-compulsive disorder.  Individuals suffering from obsessive-compulsive disorder experience continual obsessive thoughts (often causing them fear or distress) which they acknowledge to be completely unfounded (4).  However, even though these individuals realize that their fears have no basis, they are not able to dismiss the obsessive thoughts.  So, their “I-functions” are seemingly unable to exert the emotional control used by the patients in the Colombia University study (1).  This limitation could be caused by any number of factors influencing signal transmission, such as faulty neuron circuits, or an imbalance of neurotransmitters. In addition, it is very possible that the cause has a genetic component, as many families have multiple individuals suffering from the disorder (4). 

       One fascinating aspect of obsessive-compulsive disorder is the fact that patients perform specific behaviors (in the form of compulsive, repeated actions) in the attempt to alleviate their distress (4).  These compulsive behaviors can include both physical actions and thoughts that are meant to cancel out the negative affects of the obsession, although they may or may not have anything to do with the obsession itself (ex: someone may wash his or her hands repeatedly to avoid sickness, or turn a light on and off three times before leaving a room to prevent someone from getting injured (6)).  The fact that the person provides unique sensory inputs in an attempt to relieve feelings of discomfort is similar to the way in which some people suffering from phantom limb pain use a mirror box to create visual input from the absent limb, relieving the pain (5).  The problem with compulsive behaviors, however, is that they only relieve the patient’s anxiety temporarily.  Since there appear to be both biological and cognitive components to obsessive-compulsive disorder, and since both nervous system architecture and personal background/memories, etc...vary so greatly among individuals, it is likely that a combination of personalized chemical treatment and psychotherapy would be most successful in treating this disorder. 

       However, we never know what our ever-changing brains have in store for us, and it is also possible that the nervous system will find a way to correct its own imbalances, or otherwise heal itself over time.  As a person who suffered from several forms of anxiety disorder, including obsessive-compulsive disorder, as a young child, I can attest to the fact that these anxieties are extremely real (at least to the person who is experiencing them) and very difficult to control, even with therapeutic treatment.  I feel that my history enables me to view anxiety from a unique perspective.  Despite everything that I have experienced, I am still a firm believer in “listening” to what your body is telling you.  To this day, I am not entirely convinced that some of the cautions that I exercised were not to some extent beneficial.  At the very least, I feel that there are times when physiological fear responses (even when they are seemingly without cause) should be heeded and not ignored.  We cannot know what types of subconscious signal processing may be informing our autonomic nervous systems, and we certainly cannot always count on socially “normal” behaviors to be the wisest or the safest.  Further research into the biological and cultural aspects of fear is essential.  Increased knowledge of these topics would enable us to develop the most advantageous treatments for those who seek relief from anxiety, but would also help us to broaden our collective understanding of when it might be acceptable, and even advisable, to be afraid.

Sources:

1) http://www.medicalnewstoday.com/articles/53154.php, “Emotional Control Circuit Of Brain's Fear Response Discovered”, Colombia University Medical Center, October 2006
2) http://en.wikipedia.org/wiki/Fear
3) http://thalamus.wustl.edu/course/hypoANS.html, “HYPOTHALAMUS AND AUTONOMIC NERVOUS SYSTEM”
4) http://www.nimh.nih.gov/health/publications/anxiety-disorders/complete-publication.shtml, “Anxiety Disorders”, National Institute of Mental Health, April 2008
5) http://en.wikipedia.org/wiki/Phantom_limb
6) http://en.wikipedia.org/wiki/Obsessive-compulsive_disorder
7) http://www.humboldt1.com/~cr2/emotion.htm, A Cultural-Psychological Analysis of Emotions, Carl Ratner, 2000
8) /exchange/courses/bio202/s08/8aprilnotes

 

Comments

Paul Grobstein's picture

fear and the I-function

"We cannot know what types of subconscious signal processing may be informing our autonomic nervous systems, and we certainly cannot always count on socially “normal” behaviors to be the wisest or the safest."

Very interesting treatment of the issue, raising the possibility that fear is, in one way or another, a signal of mismatch somewhere in the nervous system? and hence something that should, in one way or another, be paid attention to, by the experiencer if no one else?