Glider

This makes a lot of sense, and supporting evidence can be found in the behaviour of many modern animals, so called 'flying frogs', flying lizards and flying squirrels etc.. have all evolved the ability to fly (actually protracted glide) to escape predation rather than gain food.

Well said! This is my point about cloning, it involves making decisions on the behalf of other people. I don't like this being done to me. I have no reason to suppose anyone else would like me doing it to them.

It could also be argued that those who show signs of having the greatest problems with eductaion, are also those who have the greatest need to discuss it?

I recognise that fossil. By coincidence I recently saw an investigation into it, which revealed it to be an extremely clever fake. It is not that the fossils per se were faked (not possible) but that the fossil in the picture actually consists of two fossils. The fore section (with the wings) belongs to one fossil, and the caudal section (with the long, straight tail) belongs to another. The reason this was considered an important find was that it suggested a missing link between dinosaurs and birds, a dinosaur (indicated by the structure of the tail) with wings. However, the fraud was discovered by by an amazing chance. They found the other half of that exact fossil at it's site of origin (by other half, imagine two halves of a mould which contains the bones). Finding the other half showed that the animal did in fact have wings, but that the caudal section was completely different, and that the caudal section of the fossil shown in that image, in fact comes from a completely different animal. Subsequent tests on the rock surrounding the fossil show that although the rock from the front and back ends of the fossil is the same kind of rock, and of the same age, there are elemental differences which indicate that they were formed in different locations.

That's valid. It's a part of the acquision of socially learned traits I mentioned earlier, in the context of cultural differences. Children 'learn' how to respond to pain from their parents and peers. Their parents and peers will have learned the 'appropriate' responses from social ideals concerning (e.g.) gender role behaviours and so-on. If we accept that emotion is a significant component of pain. Then the socially acquired 'traits' determining the 'appropriate' emotional responses to a painful event, must also (partly at least) determine the ultimate experience of pain. This goes some way to explaining the observed (between) individual differences in the perception of pain related to sex, ethnicity and cultural affiliation.

Out of interest, is anyone here involved in research, and if so, do you consider it de rigueur to run power analyses to calculate your sample sizes?

Tetanus?...Ow!...bummer! That's very interesting. It fits with what Skye said about being bitten by a dog too: In light of this, would it be fair to say that emotion must be a significant component of pain? In other words, that it is not so much the intensity of the stimulus (or the degree of tissue damage), which determines the pain experience, but our emotional response to it?

So, in a sense, it's filling the vacuum that nature so abhors?

That's a good idea, and that's what was thought a short time ago. Unfortunately it turned out not to be the case. Positron Emission Tomography and functional Magnetic Resonance Imaging has shown that when participants are subjected to a painful stimulus, no single area of the brain 'lights up'. Rather most of it does; the reticular system in the brain-stem, the hypothalamus and thalamus, the medial temporal regions (hippocampus, amydala), the pre-frontal cortex, (including the areas of the anterior cingulate gyrus), the visual cortex, the primary and secondary somatosensory cortices and association areas of the cortex. This would suggest that as with emotion, the experience of pain is a function of circuitry, rather than specific, dedicated 'pain centres'.

Hehehe:D

Here's another very good example. Chapman (1984) relates the story of a 9 year-old boy he observed in hospital, just after the boy had undergone a nephrectomy. "As soon as he recovered from the anaesthetic, the boy was transferred to his room. He was given no drugs for postoperative pain in accordance with his surgeon's normal practice. A colleague and I had involved the boy in a transcutaneous electrical stimulation experiment in which electrodes were attached under the bandage and stimulation was initiated before the patient regained consciousness. As the youngster lay in bed with his hands outside the covers, the surgeon and his associates came to visit. The surgeon told him that he could not drink water for the entire day and gave other instructions. Since an experimental intervention was being tried, they repeatedly asked if he felt any pain in his belly. He said, "No, it doesn't hurt", to repeated queries, and everyone was impressed with the apparent success of our intervention. After the surgeon and his retinue had gone, the boy talked more casually with the others in the room. When asked whether there was anything he feared, he began to cry and confessed his terror of the expected operation that would remove his kidney. His surprised nurse tried to reassure him that the surgery had already been done, and that there was nothing to worry about. He refused to believe her. "But don't you remember?" she contended, "That's why they put you to sleep this morning...so they could do the operation". The little boy looked very threatened. "It's not true!" he shouted, "It's not true!" When asked why it couldn't be true, he asserted confidently, "Because I haven't got any bandages". We asked him to feel his belly, since his hands were outside of the bedclothes. When he did, an expression of astonishment came over his face, and he broke into tears, screaming, "It hurts! It hurts!" Thus, the boy's 'analgesia' occurred because no one had told him that he had been operated and not because of our stimulation therapy" Something to think about there. It's odd, when you consider that of all things, pain (or more precisely, suffering, as the complete absence of pain would be catastrophic) is probably one of the few experience all humans have in common. Every single individual on the planet (barring those with universal insensitivity) will experience it at some point in their lives, and usually more than once, and with varying degrees of severity. Yet we seem to having a real problem providing a clear and universal definition of it. Interesting, don't you think? Chapman, C. R. (1984). New directions in the understanding and management of pain. Social Science and Medicine, 19 (12), 1261-1277.

Well, this is the problem. Pain is a non-observable phenomenon, we can't measure it like we can blood pressure for example. So, all we have to go on is behaviour and verbal report. People in pain will exhibit 'pain behaviours' (e.g. sheilding, antalgic gait, writhing, moaning etc., etc.), and when asked, will genrally not be shy in telling you if something hurts. In the case of the celebrant described above, he exhibits no pain behaviours, and talks normally to those around him. From these observations, we can only conclude the absence of pain. As for cultural differences, whilst there are differences in the perception of pain that are related to ethnicity and cultural affiliation these differences (whilst statistically significant) are nonetheless very small. Moreover, the evidence suggests that these differences are a result of social learning within cultures, rather than any physiological factors. In short, we have a guy who is not so different from any other guy, yet who appears to suffer no pain whilst suspended by hooks inserted under the muscles lateral to his spine. Pain is a conundrum, innit?

Stimulus that reacts to a reflex arc? Of stimuli that trigger a withdrawal reflex, some may be interpreted as painful, some may not. The point is the the reflex arc is not the determinent of whether or not such stimuli are percieved as painful. For example, you're out camping and you're sitting around the fire, having a beer and you reach behind you to pick up a new tinny, and your hand contacts something unexpected (say, cold, slimy and moving). That will probably trigger a withdrawal reflex, probably scare the crap out of you too...but it won't be painful. The example you give above, concerning the hot coils on the oven will also trigger a withdrawal reflex, but in this case, the stimulus would probably be perceived as painful. Either way, it has nothing to do with reflex arc. That simply mediates the reflex, not the experience.

Arguably yes. You could say that (as with a broken bone) any trauma which results in a severe inflammatory response (e.g. the release of histamine, prostoglandins and substance P) is pain. The problem here though is twofold. 1) The stimulus (trauma) is not pain. Whilst we may reasonable expect trauma to be painful, the trauma itself is not pain per se. Rather, pain (usually) occurs as a result of trauma 2) There are exceptions to the rule that trauma results in pain. A good example is the Indian Hook Swinging ceremony which involves a man (the celebrant) having steel hooks inserted under the muscles on each side of his spine. These hooks are attached to ropes, which in turn are attached to a cart. The celebrant is suspended by these hooks and wheeled from village to village where he blesses crops and children. Although he holds the ropes between villages, he swings freely whilst giving the blessings. The trauma of the instertion of these hooks would by western standard be considered agonisingly painful. However, the celbrant shows no sign of discomfort, rather, he seems to be in a state of exultation (see Melzack & Wall, 1982). At the other end of the scale, there are examples of extreme pain occurring in the complete absence of any discernable physical cause. People have even been known to hallucinate pain. So, at two ends of a scale, we can have extreme pain with no physical cause, and an extreme physical 'cause' (trauma which one might reasonably expect to result in pain), in the apparent absence of pain. Melzack, R., & Wall, P. (1982). The Challange of Pain. New York: Penguin.

This is true enough. Unfortunately, it's where a lot of the problem lies, as when assessing pain in another, the clinician can only relate the patient's description to his or her own experience. That seems to leaves room for quite a lot of error doesn't it? This especially becomes an issue when trying to control pain. Imagine you've just had surgery, and I'm part of the pain-control team. I come to you and say "Good morning, how much pain do you have today?" You say "A lot!" and this is what I base your dosage of morphine on?

Very true. And yet it still has nothing to do with pain.

This could probably be explained by the different receptors involved. Small thinly myelinated fibres (A-delta) mediate sharp, fast pain, whilst very small, non-myelinated © fibres mediate slow, dull aching pain and heat. It's like when you stub your toe, you get the impact (large afferents) and the A-delta mediated sharp, fast shocking pain, but you also have that knowledge that in a second, it's really going to hurt. A split second later, you get that deep aching pain that makes you sweat. A very good point. Past experience is definitely a factor in the experience of pain. What's most interesting here though, are the changes in your subjective experience (you say it hurt more, and differently) when you looked at the damage. That's very interesting.

Hey, we all have our hobbies! As for pain, it's what I'm researching. Arguably, to research something effectively, we need to at least be able to define it. There is a definition provided by the International Association for the Study of Pain (IASP), but I was just interested in what normal people thought. D'you think I'm in the wrong place?

True. That would be a test of memory.

Being a self-contained functional unit, the reflex arc is not dependent upon higher mechanisms. You could, in effect remove the brain and the reflex arc would still function (this has been shown in animal studies). In this case, yes; you would jerk your hand away from a hot coil on your oven, but not feel the heat. To approach it from the 'other end' as it were, if you touch the hot coil and burn your hand, the withdrawal reflex will limit the damage. However, the pain of the burn will persist (possibly for hours). Yet you would not be constantly withdrawing your hand, i.e. the reflex arc would not respond to the persisting nociceptive volleys. This suggests that the reflex arc is not a mediator of pain.

."The strongest knowledge (that of the total unfreedom of the human will) is nonetheless the poorest in successes, for it always has the strongest opponent: Human vanity." Nietzsche. Human, all too human Whilst I wouldn't go as far as citing the 'total' unfreedom of the human will, I do think that most people would be surprised at the degree to which our emotions and behaviour is not a matter of choice. I do not believe that freedom of will is one half of a dichotomy (i.e. either we have free will or we don't), I believe is is a question of degree. There is a significant body of recent research (stemming from the work of people like Robert Zajonc, who suggested the primacy of affect in 1980), which shows that a significant proportion of human thought and behaviour is driven by factors outside our control. Models of automaticity (see e.g. John Bargh, Tory Higgins, Mark Chen) suggest that the propensity for most of our thoughts and behaviours is driven by social and environmental factors working on a level outside our awareness (i.e. pre-conscious). This is not simply a philosophical question. There is a growing body of empirical evidence in support of this, including neurophysiological data.

Very true. But in the case of self-harm, the needs are maladaptive. In the case of addiction, the needs are substance driven (i.e. fulfilling the need to avoid withdrawal). e.g. People who have never used heroin, don't feel the need to do so, and are not stressed by not doing so. It could be argued that as behaviours, the examples of self-harm and addiction are exceptions rather than the rule. So, what about normative behaviours? Are these all inherently selfish? Quite possibly. There are several theories of social behaviours. One is pertinent here. The Social Contract theory, which (broadly) states that all behaviour is ultimately self serving. It suggests that people form 'social contracts' and that pro-social (altruistic) behaviours are simply a way 'buying' the same behaviour from another (you scratch my back, I'll scratch yours). This is said to have evolved as an adaptive mechanism which provides social animals who engage in it an 'edge' (e.g. I'll keep a look out whilst you eat, if you keep a look out whilst I eat). This increases the probability of survival and thus reinforces the trait. There are alternative theories however. One of which, for example, suggest that true altruistic behaviour is a reality. It suggests that the function of this is again adaptive, in that whilst it may be detrimental to the individual, it increases the chances of survival for 'related genes'. In this case, altruistic behaviours are more likley to be displayed towards those who most closely resemble ourselves (indicating those who are likely to posess familial genetic material). This provides an advantage to a 'gene pool' rather than a small social group, but nonetheless, such an advantage would result in that behavioural trait being reinforced in the population as a whole. There are more, but but these two are pretty much opposites. Take your pick.

The reflex arc is a self-contained functional unit. It has been shown to exist in decortecised animals, cockroaches, sea slugs, flatworms etc.. It is an adaptive hard-wired mechanism for limiting tissue damage on exposure to a potentially harmful stimulus. Fine. We accept that. It's not pain though, nor does it indicate the existence of pain. Can anyone give me a considered, working definition of pain?

Melanin does protect against UV radiation. Tanning is a defence mechanism; pale skins burn, tanned skins are protected. This is the basis of the main theory concerning the advent of white skin. Vitamin D is produced through the action of sunlight (UV) on the skin. This is our ONLY source of vitamin D. Black skin takes around 4 times the intensity of UV to produce the same amount of vitamin D as white skin. This is fine in equatorial regions. However, as the species migrated north, the intensity and duration of sunlight reduced. Those individuals with paler skins then had an advantage over those with darker skins, as they could maintain levels of vitamin D where those with darker skins could not. The problem of vitamin D deficiency still exists in dark skinned people who live in more northern regions, and is pronounced in some individuals, notably those who, in line with their religion, spend a great deal of time completely covered. Problems associated with vitamin D deficiency are hair loss, a loosening of the teeth, rickets and skin problems. In the UK for example, a white skinned person synthesises sufficient vitamin D only from around June, to about halfway through september. The amount of vitamin D produced in that time has to last the individual througout the winter when the sun (even when it's out) is too low in intensity and duration.

It's Adam, not Addam. And the (mis)quote you're looking for is: Then the LORD God made a woman from the rib he had taken out of the man, and he brought her to the man. The man said, "This is now bone of my bones and flesh of my flesh; she shall be called 'woman', for she was taken out of man." For this reason a man will leave his father and mother and be united to his wife, and they will become one flesh. Genesis If you're going to quote it, might be an idea to read it.