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48

There are fundamental problems with defining what it means for an animal to feel pain, especially when the animal is a life form as different from us as an oyster. I wasn't able to find any specific info online about oysters, but there is quite a bit of information that allows us to reason by analogy with related species. Oysters are molluscs, and molluscs ...


17

We really don't know - we can't really ask the chicken. At least, it's unlikely it's as painful as it can be with humans. The reason human birth is (or can be) very painful is that the human baby's head has to fit through the woman's pelvis. Since splitting from chimpanzees, human heads have gotten bigger, while the pelvis has gotten more narrow due to ...


16

Yes, this is pretty common. Examples include sciatica, pain felt down the back of a leg to the foot, from irritation to components of the sciatic nerve but commonly at the level of the sciatic nerve roots angina pectoris, pain from myocardial ischaemia felt in the throat (Latin angina "infection of the throat"), arms, chest etc shoulder tip pain from a ...


13

It has mainly to do with the embryonic origin of organs, with the heart being a typically left sided organ, it develops sharing some nerves with the left thorax and left arm. There is however high variability, typically among patients but also among coronary vessels. For instance, right coronary stenosis may lead to abdominal pain, whereas left circumflex ...


11

For question 1 it's just a biochemical response from thermoreceptor nerves in the skin, temperatures that are likely to cause lasting damage from prolonged exposure cause a neurological response - in this case it's pain. In address to question 2 it is most likely down to the physiological response of vasoconstriction. When the body is cold the body ...


9

Pain is subjective Pain is a subjective experience; you cannot even tell with certainty how much pain your fellow human is experiencing, which is why we ask people; they then can tell us. Pain relief (both physical and emotional) is a significant part of medicine, yet we still have "pain scales" for self-reported pain, one of the more common ones being the ...


9

I believe every living organism (even single cell ones) experience pain somehow, because it is important to stay alive. The scientific answer depends on how you define pain... Related articles: Evidence suggests that some, if not all, invertebrates have the potential to suffer through current practices that do not take into consideration that ...


8

Opiate pain killers or pain killers that act on opioid receptors have a different mechanism of action than NSAIDs. They tend to act as receptor agonists which exert their effect on the CNS (oxycodone as an example). Opioid receptors are associated with analgesia, CNS depression, sedation, etc. Tylenol on the other hand is thought to exert its effect by ...


7

I answered the other question and it is similar. However, this one is different enough that I will give a slightly more simple explanation. Nerves transmit messages using electrical current, more specifically the flow of sodium and potassium. Just remember that it's electricity. When you have any sort of cut or damage, your body recruits white blood cells ...


7

It is very unlikely that oysters feel pain however it's not clear what the question actually means What does it mean to say something feels pain? The most reductive biological interpretation is to say that "feeling pain" is simply the capacity to sense damage, or the threat of damage, to the body and communicate that to the nervous system in a way that ...


6

I very much doubt it. You may however die from whatever's causing the pain. The reason you feel pain is so you stop doing whatever is causing the pain. Hence someone knows not to touch a hot fire because it is painful. But the pain itself is not actually the danger - it's the fire burning away skin. So pain is actually a good thing, a survival mechanism. So ...


6

I believe what you are referring to is called 'sympathetic pain,'and the reason you can't find any papers on the subject is because it is not really a well studied concept. That is primarily due to the lack of robustness in the sensation and idiosyncratic nature of the phenomenon. Personally, I'm not too familiar with the concept beyond placebo treatment of ...


6

An example of pain evoked by distant sites in the body is referred pain. It's defined as pain perceived at a location other than the site of the painful stimulus. An example is the case of angina pectoris (chest pain), caused by myocardial ischemia (decreased oxygen supply to the heart due to a narrowing or complete blockage of the coronary arteries). ...


6

When you touch an object, a compression wave from the collision travels through your body at the speed of sound. A sensor at any depth in your skin can pick up that signal at roughly the same time as the collision. When you touch a hot object, heat from it moves into your body via conduction and to some extent radiation. That heat flow moves much more ...


5

I don't want to comment about the nature of electric signals in neurons (as I know only little about physiology and neurophysiology). But here is a short answer that may already help you. Neuronal electric signals are called action potential. If you register the voltage at a given location on the axon of a neuron through time you will see something like ...


5

Typically nerve compression or a "pinched" nerve is due to inflammation in the tissue through which a nerve passes. The gap is already quite narrow so any inflammation is quite potent. Inflammation causes you to feel things as more painful (hyperalgesia). In a similar way to how of you burn your hand then poke it, it hurts, when cells are damaged the ...


5

The redden area around the grayish-white indentation of the canker sore isn't filled with anything. This circular area is simply inflamed. The grayish-white area in the center is not filled with puss or anything else as well. This is an area of dead cells but underneath this layer of dead cells the tissue red [1],[2],[3]. Canker sores, Aphthous stomatitis, ...


5

Short answer Sciatic nerve pain cannot be caused by a full colon. background The sciatic nerve runs at the back of the pelvis down the the leg. The sciatic nerve exits the spine from the lumbar spine to S3 in the sacrum (Fig. 1). Fig.1. Left: sciatic nerve overview. Right: Sacral plexus. Source: Manchester Bedford Clinic Hence the sciatic nerve does ...


5

Another common medical condition that causes pain elsewhere is the spinal disc herniation. The disc pushes against the nerves in the spinal and causes pain, usually in the leg, foot or arm. https://en.m.wikipedia.org/wiki/Spinal_disc_herniation Sometimes the pain disappears with rest, sometimes surgery is necessary and sometimes the pain partly remains even ...


5

Yes they feel pain, at least in certain areas of their body without a doubt. Research has been done to test whether they feel pain consciously (a signal to the brain that is perceived allows for learned response) or if it is just a reflex response (Nociception), and there is good evidence they actually perceive it especially in the antenna. source Source ...


5

To answer if lobsters have a nervous system: YES References: Mapping of serotonin-like immunoreactivity in the lobster nervous system BS Beltz, EA Kravitz Journal of Neuroscience 1 March 1983, 3 (3) 585-602 http://umaine.edu/lobsterinstitute/education/life-of-the-american-lobster/anatomy-biology/ Bonus picture:


4

As AndroidPenguin described the nociceptive pathways are activated by inflammation or noxious chemicals. Sometimes pain can arise independent of active nociceptive pathways. Most evident in cases of Neuralgia and perhaps in case of Pseudoneuromas. In certain cases the injured nerve causes disinhibition of the pain pathways arising from the dorsal horn of ...


4

The accuracy of sensation is actually quite variable depending on the region of our body. Highly innervated areas such as our fingers have a higher degree of accuracy than sparsely innervated areas such as our legs. There is a simple experiment you can do to illustrate this. Close your eyes and then get a friend to lightly and slowly run their finger from ...


4

Cortisol produced from the zona fasciculata of the adrenal cortex is directly caused by stress. According to http://en.wikipedia.org/wiki/Cortisol Cortisol stimulates gastric-acid secretion. Cortisol's only direct effect on the hydrogen ion excretion of the kidneys is to stimulate the excretion of ammonium ions by deactivating the renal glutaminase ...


4

Short answer No, orally taken painkillers act systemically. Background Taking a painkiller orally results in the drug being taken up into the bloodstream by the digestive system. From there it can potentially reach all tissues. In other words, a pain response does not act as a chaperone. A hypothetical drug that would home in on tissues with a pain ...


4

As far as I know, adaptation of peripheral receptors, including pain receptors, is transient (Giniatullin & Nistri, 2013) Instead, my educated guess is that the increase in subjective pain threshold plays an important role. Pain thresholds differ between the sexes (Chesterton et al., 2003), and depend on disease and physical status (Kosak et al., 1996)....


4

Our pain-sensing neurons work in useful ways only when they inform about skin areas or muscles. When nettles sting your left hand, you want to retract your left hand right away. This is in part an educated reaction, because your brain ca re-learn what sensing neuron corresponds to what side of you hand when surgeons stitch together broken nerves. With ...


4

First, there is some confusion on your part about heart cells and pain perception. Heart cells generate an action potential intrinsically; they do not need the central nervous system to beat (your second article explains this; read the part about the importance of calcium.) So yes, long before a fetus can feel pain, the heart is beating, because there must ...


4

Before answer, What intuitively seems: Lobsters structurally contains sense-organs like eye and antennae, and output organs like muscles through which they move. So plausibly these organs should be plausibly connected to its controllers, i.e. neurons. The basic histology found in very primitive multicellular animals like Hydra, Planaria to advanced ...


4

tl;dr Like the brain, the receptors commonly called 'pain' receptors aren't in the spinal cord itself, but they are present in the meninges around the cord, and damage to the cord can be perceived as pain in particular because it can increase activity in the pathways carrying 'pain' information to the brain. Details Nociceptors, often called pain ...


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