Pain Perception Essay, Research Paper

The perception of pain sensation is a combination of psychological and biological components intertwined. Pain is a part of life, and like many of life situations people do not share the same perceptions, especially relating to pain. experiences relating to pain. Pain can occur by a stimulus and often is influenced by emotions, stress, tissue damage, medical history and even gender. Gender has been one of the major differences in the effects of pain thresholds. Pain is normal and even natural. It is important to inform and learn from. Biological factors in pain perception are a part in everyday life. A hypothetical example to illustrate this could be if a person drops a heavy object on their toe, nociceptors will respond to the intense pressure sending information to surrounding cells. Once the cells link the sensation to the neural circuit of the spinal region information reaches the brain to explain why the toe is in pain. Psychological factors are very different; the amount pressure from the object dropped may be interrupted by the level of anxiety or stress a person is feeling or by the previous emotional history. Researchers intrigued with this subject have performed several experiments on people to find out a person s threshold for pain, among which have been electric shock, thermal testing and various extensive questionnaires. Results show differences male and female subjects pain thresholds.

Research supporting biological evidence fitting human sex differences in pain thresholds concludes that males have a higher tolerance for pain. Researchers at the University of Georgia performed a thermal test on 18 men and 24 women all health in their early 20 s. They were asked questions about their pain and medical history then were administered the cold pressor test. Then asks the subject to submerge their dominant foot into an ice bath between 0 a- 4 aC for 2 minutes. The experimenter asked the participant to rate the pain aloud on a scale from 0, meaning no pain at all to 11, unbearable pain. The results showed women to have higher rates of pain intensity, pain frequency, and higher blood pressure than the men participants. The researchers found that in their reports women had more of a history of using analgesics and in general more pain episodes in their daily life. (Allan, 2000) Evidence of this higher sensitivity in women is explained somewhat by the increased reactivity of the hypothalamus-pituitary gland. The hypothalamus is responsible for muscle contraction, autonomic function, nerve activity, hormone secretion, emotional drives, behavioral drives, regulation in body temperature and coordination between voluntary and autonomic functions. (Martini, 1998) Because of such high responsiveness in females, researchers believe growth hormones, prolactin, ACTH, and corticosterone are released in greater amounts. (Menetry, 1997) With all this information presented from the effects of the hypothalamus its no wonder women are more sensitive to pain. When hormone levels are not stable pain symptoms are perceived more drastically.

In another study performed at the University of Marburg, Germany researchers found that women have a higher risk of suffering from pain more than men due to differences in the balance of pain excitatory and pain inhibitory processes. In Berkley s study he argues that the pain system is homeostatic, meaning pain has relatively constant internal environment within the body. (Martini, 1998) The excitatory activity should balance the inhibitory activity pain signals, according to his evidence. Examples in the adaptation levels in which a person perceives pain after a preceding strong noxious stimulus were more intense than after preceding a weak one. (Lautenbacher, 1997) Another way he evaluated his work is by diffusing the noxious inhibitory control, meaning he was testing how sustained pain can weaken other pains in the body. He found out that the more pain is reduced and controlled in the past the more pain a person could feel in the long run. (Lautenbacher, 1997) Its sort of like taking antibiotics, if every time a person gets sick and takes a medication the less likely that person is to feel well without the use of medication each time they are ill. Medications can be less effective when administered so often because people build tolerance to them and the same is somewhat true for pain. Although he could not find a specific biological proof, it is clearly observed that not all excitatory activity is balanced out by inhibitory activity. He concludes that maybe women have more powerful inhibitory systems to allow such a difference between the sexes.

At the University of Degli Studi in Milan, Italy cardiovascular specialists came up with some requirements for a biological hypothesis concerning pain perception between genders. Focusing on the differences between the sensibilities of cutaneous and visceral tissues they concluded that visceral nociceptive sensations comes from intensity not from specific mechanisms. (Menetray, 1997) The viscerosensory system is responsible for monitoring internal organs by receptors surrounding them to interrupt information. (Martini, 1998) Affirming or denying the existence of a peripheral neural channel specifically transmitting the algogenic code responsible for visceral pain can be based on physiological data on urine samples, tests on reproductive organs and cardiac analysis s. (Menetray, 1997) To test stress complexity causing pain doctors studied the impulse activity of single afferent sympathetic fibers innervating the heart. They found signs of ischemia, a sign of too much pressure in the ventricles of the heart by the way an electrocardiogram s wave inversion. (Menetray, 1997 and Stein, 2000) In relation to pain, pain that is elicited with a strong stimulus will reflect the same way ischemia does on an EKG suggesting angina (cardio pain) or no sensation of pain. The same test is somewhat true when testing urine. Pain or injury can be detected in urine because there are so many high threshold mechanosensitive afferent receptors that have nerve endings in the urinary bladder. (Menetray, 1997) Unfortunately, this detection only has been tested on different genders in animals because such high pain thresholds are admitted. Although their entire hypothesis has not been completely proven yet, this research has opened a new window for many researchers to compare their own findings to.

At the University of Western Ontario, Canada, the department of psychology confirmed a biological role in pain between genders. Testing with electrocutaneous stimuli women were found to have a lower pain threshold than men. Even though data was not very significant women tended to average a 5 and men a 7 on a scale 1 to 10. However, in the thermal test the difference was much smaller, but still had high intensity ratings above 7. The biological role concerning this test mainly looks at how anxieties to the tests are interrupted by genes transporting serotonin. Serotonin is a central nervous system neurotransmitter responsible for the effects of attention and emotion. (Martini, 1998) Scientists say that females exhibit a lower tolerance to pain stimulus, so maybe too much serotonin is being released in females. Tests shown from female patients that their body releases great amounts estrogen binding receptors on a releasing hormone gene called corticotrophin, (CRH). CRH is in return linked to the hypothalamus-pituitary gland, monitoring stress. (Rollman, 1997) Another interesting insight to their reach in Canada is how somatosensory amplification is much stronger in women meaning their external responses are more acute. Females in general were found to of taken better care of themselves, they got medical attention when they felt pain. (Rollman, 1997)

Research supporting the psychological human sex differences in pain thresholds focus much on emotion, anxiety sensitivity, health, self discipline of pain tolerance as well as other various other psychological related topics. At the University of Leiden, in the Netherlands, Dr. Uwe Hentschel, head of the psychology department claims that emotional stability relates to the neuroticism of pain tolerance. (Hentschel, 1999) He admitted the cold pressor test to 40 participants. The instructions were to hold their hand in the ice cold water as long as they could up to a maximum 6 minutes. He focused a video camera to evaluate the facial expression while no one was in the room except the participant. His results showed that the majority of females gave a prominent look of fear on their face where as male subjects looked more positive. The females also predicted a positive fear of failure where as males exhibited a more negative fear of failure previous to the test. The men in general were more willing to endure a higher subjected pain while at the same time tried their best poker face . After the test, a questionnaire was given to the participants to evaluate their responses, personality and history. According to the questionnaire all the participants that were females alluded to a lower emotional stability in their daily life where as males seem more secure emotionally. The results were well correlated with physical evidence, and psychologically could explain why females weren t able to hold their hand in the ice water longer. (Hentschel, 1999) They also found significant correlations with the questionnaire that self-disciple in not related to pain. Almost all the subjects were responsible young adults in their early 20 s and 30 s.

At the University of London, Julie Birkby relates how anxiety sensitivity might effect gender on the experience of pain. First of all, anxiety sensitivity is defined as a trait tendency to experience fear of anxiety-related situations such as rapid heart beating, palpitations and sweating because they cause harm. (Birkby, 1999) People who have experienced a heart attack should naturally fear a rapid heart beat, just like people who have asthma should fear rapid breathing. Having awareness over ones body is a strong link to anxiety experience. In a test known as the carbon dioxide challenge, participates are prompted to breath deeply and rapidly CO2 for 2 to 3 minutes. Results showed that people with high anxiety reported strong feelings of pain and were more likely to have hyperventilated. Individuals with extreme hyperventilation commonly had a high long history of panic attacks as well as lots of stress in their daily life. Another comparison that was made is that females suffered more anxiety than males in this particular challenge. Anxiety sensitivity is associated with increased vigilance of such powerful sensations that the greater pain-related expectations seem to be associated with increased anxiety levels. (Birkby, 1999) Hypothetically researchers predicted that: When using self reported measures of pain, those high in anxiety sensitivity would report more intense negative pain sensations. In particular, those high in anxiety sensitivity were expected to report greater sensory and affective pain. Those in high in anxiety sensitivity would exhibit a lower pain threshold and low pain tolerance. Females would report greater negative pain, low pain threshold and low pain tolerance then males. Anxiety sensitivity and gender would interact to effect pain differences, with females high in anxiety exhibiting the negative experience of pain. (Birkby, 1999) Like many of the pain induction techniques the cold pressor task was administered. (Chapman et al, 1985) People involved in the test showed typical results just like all the other cold pressor thermal tests. After the test the McGill Pain Questionnaire was employed to measure a number of dimensions of the pain. The form is separated into four areas, the visual awareness line, the present pain scale, the 11 point sensory pain description and the four affective pain descriptive analysis. The Visual Awareness Line based on a 10cm line with no pain at one end and maximum pain at the other, and the participant marks the spot on the line appropriate to represent their pain. The Present Pain Scale is based on a 6 point range with 0 as no pain and 6 as maximum pain. The 11 Point Sensory Pain Description is based the sane way as the present pain scale, except has 11 points to choose from and the subject circles the best fitting description. Finally the Four Affective Pain Descriptive is based on four points as 0 is no pain and 4 is the most. (Birkby, 1999) As the hypothesis predicted all factors were true, and the results explained that anxiety is enhanced with pain, and even more so with people who have had previous anxiety especially women.

A team of researchers from the University of Muchern, Germany evaluated male and female recovering cardiac patients for various psychological information relating to pain threshold. Distressed women commonly were found to suffer more anxiety, depression and even sleeping disorders. Their cardiac recovery was recorded as more painful than male patients were. (Holle, 2000) The team took a closer look to evaluate emotional disability by interviews. Results showed women to be more prone to a negative impaired emotional state just by experiencing extreme levels of pain. In terms of health perception women still have more significant poor health conditions such as fatigue, sleep disturbances, emotional dissatisfaction and even social isolation. All of those factors contribute to the low tolerance to pain stimulus, in particularly their cardiac stresses. (Holle, 2000) However, none of this can be completely proven just by the basis of the specific cardiac patients in Germany. Gender differences in pain are infinitely an ongoing research in much relation between a biological and psychological approach.

In conclusion, hormones and the hypothalamus-pituitary gland are responsible for connections between females and low pain thresholds biologically. The most common way to test pain threshold biologically is the cold pressor thermal test, and reviewing pain history. Psychologically, anxiety and other emotions