jueves, 15 de abril de 2010

Fear and death

Psychologists have addressed the hypothesis that fear of death motivates religious commitment, and that it may be alleviated by assurances about an afterlife. Empirical research on this topic has been equivocal.[citation needed] According to Kahoe and Dunn, people who are most firm in their faith and attend religious services weekly are the least afraid of dying. People who hold a loose religious faith are the most anxious, and people who are not religious are intermediate in their fear of death. A survey of people in various Christian denominations showed a positive correlation between fear of death and dogmatic adherence to religious doctrine. In other words, Christian fundamentalism and other strict interpretations of the Bible are associated with greater fear of death. Furthermore, some religious orientations were more effective than others in allaying that fear.
In another study, data from a sample of white, Christian men and women were used to test the hypothesis that traditional, church-centered religiousness and de-institutionalized spiritual seeking are distinct ways of approaching fear of death in old age. Both religiousness and spirituality were related to positive psychosocial functioning, but only church-centered religiousness protected subjects against the fear of death.
Fear of death is also known as death anxiety. This may be a more accurate label because, like other anxieties, the emotional state in question is long lasting and not typically linked to a specific stimulus. The analysis of fear of death, death anxiety, and concerns over mortality is an important feature of existentialism and terror management theory.
Neurobiology

The amygdala is a key brain structure in the neurobiology of fear. It is involved in the processing of negative emotions (such as fear and anger). Researchers have observed hyperactivity in the amygdala when patients who were shown threatening faces or confronted with frightening situations. Patients with a more severe social phobia showed a correlation with increased response in the amygdala. Studies have also shown that subjects exposed to images of frightened faces, or faces of people from another race, exhibit increased activity in the amygdala.
The fear response generated by the amygdala can be mitigated by another brain region known as the rostral anterior cingulate cortex, located in the frontal lobe. In a 2006 study at Columbia University, researchers observed that test subjects experienced less activity in the amygdala when they consciously perceived fearful stimuli than when they unconsciously perceived fearful stimuli. In the former case, they discovered the rostral anterior cingulate cortex activates to dampen activity in amygdala, granting the subjects a degree of emotional control.
The role of the amygdala in the processing of fear-related stimuli has been questioned by research upon those in which it is bilateral damaged. Even in the absence of their amygdala, they still react rapidly to fearful faces.
Suppression of amygdala activity can also be achieved by pathogens. Rats infected with the toxoplasmosis parasite become less fearful of cats, sometimes even seeking out their urine-marked areas. This behavior often leads to them being eaten by cats. The parasite then reproduces within the body of the cat. There is evidence that the parasite concentrates itself in the amygdala of infected rats.


Most behavioral therapies for fear extinction focus on exposure. For instance, therapy for a person with a fear of snakes might involve visiting a snake farm repeatedly and taking small steps toward touching one. First, the person might get within 10 feet of the snake and see that nothing terrible happens. Then he might get within 5 feet of the snake. When nothing terrible happens within 5 feet of the snake, he might get close enough to touch it. This process continues until new, fear-extinction memories are formed -- memories that say "snakes are not going to harm you" and serve to contradict the fear of snakes that lives in the amygdala. The fear still exists, but the idea is to override it with the new memory.
Fear is an emotional response to a perceived threat. It is a basic survival mechanism occurring in response to a specific stimulus, such as pain or the threat of danger. Some psychologists such as John B. Watson, Robert Plutchik, and Paul Ekman have suggested that fear is one of a small set of basic or innate emotions. This set also includes such emotions as joy, sadness, and anger. Fear should be distinguished from the related emotional state of anxiety, which typically occurs without any external threat. Additionally, fear is related to the specific behaviors of escape and avoidance, whereas anxiety is the result of threats which are perceived to be uncontrollable or unavoidable. Worth noting is that fear almost always relates to future events, such as worsening of a situation, or continuation of a situation that is unacceptable. Fear could also be an instant reaction, to something presently happening.<+The Old English term fear meant not the emotion engendered by a calamity or disaster, but rather the event itself. The first recorded usage of the term "fear" with the sense of the “emotion of fear” is found in a medieval work written in Middle English, composed circa 1290. The most probable explanation for the change in the meaning of the word "fear" is the existence in Old English of the related verb frighten, which meant “to terrify, take by surprise”.