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Nausea from vertigo: an evolutionary by-product?

  1. Aug 7, 2016 #1
    Why do humans (and other mammals) get nauseated from dizziness or vertigo?
    I can see the evolutionary advantage of nausea from food poisoning, but I can't see the direct "link" between vertigo and vomit.

    I found something on verywell.com:
    There it says that "It's an unintended result of the body thinking any problem with the brain has to be because of something you ate."
    Is it just a by-product, or might it have some selectionary advantage?

  2. jcsd
  3. Aug 7, 2016 #2


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    I don't know (as any kind of expert) but I would think that it is a safety warning to keep from falling off cliffs. Yes, the vomiting may be because there's the tie-in that you reference to food poisoning but that's secondary. The main thing is the warning and it's less important how the warning gets to you.

    I can't think of any mammals other than humans that get that vertigo but there may be some. Clearly most (cats, apes, monkeys, etc) don't. Also, I think most mammals, because they are 4-legged, have confidence in their sense of balance so would have no reason to be afraid of something like a cliff edge.

    EDIT: I should add, I have no sense of nausea whatsoever when my fear of heights kicks in. With me it's a sense that my bladder and sphincter are going to let go whether I like it or not. It never happens, but then I stay away from the edge of cliffs. Oh, and I DO get dizzy, just not nauseous.
    Last edited: Aug 7, 2016
  4. Aug 7, 2016 #3
    That's an interesting point about the 4-legged mammals with better balance.
    Were you thinking safety warning as in the brain signalling to to the muscles to reduce movement?
  5. Aug 7, 2016 #4


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    I'm thinking of the brain signalling to the whole body LET'S GET THE HELL OUT OF HERE !!! I know for sure that's what my brain says if I'm even 6 feet up on a ladder. If I were stand really close to a high cliff (at the top) I'm pretty sure my bowels would empty themselves without my volition. BUT ... there are a lot of people who are not at all afraid of heights. High-wire artists come immediately to mind but there are plenty of others.

  6. Aug 7, 2016 #5
    The nausea and vomiting from irritation of nerve endings in the stomach, so one can associate perhaps a link between cause and effect. Whether it is an evolutionary advantage is debatable. While you are vomiting, you, as a stationary prey, become an easy target to be just be eaten up.

    Nausea associated with other causes such as anxiety, motion sickness, infection, other disease is not well understood.
    Why, for example, should the body's reaction be of a feeling of nausea and vomiting when overwhlemed emotionally by particular visual or auditory input?
    The body's balance system - vestibular - can go out of whack producing spacial disorientation, dizziness, vertigo, loss of balance, and of coarse, nausea.
    The brain's circutry would have to be wired in some way to produce these symptoms.

    All mammals have a vestibular systems, so I am not so sure if 4 legs protects them completely.
    In fact, dogs are used as subjects for study.
    Here is some written words regarding your best friend, the dog.
  7. Aug 7, 2016 #6
  8. Aug 7, 2016 #7
    I find that interesting. It just goes to show that we are not all "exactly" like our ancestors living in trees.
  9. Aug 7, 2016 #8


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  10. Aug 7, 2016 #9

    jim mcnamara

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    Infants learn to be wary of heights, there is no 'innate' fear of heights which is what would be posited by a genetic trait. I think the OP conflated learned behavior and genetic traits in the OP. YMMV. This is in support of @phinds point.

    If you google 'early development fear of heights' you will see a link to pdf from psych.nyu.edu - KE Adolph et al. This is a review of the topic and has great diagrams. It is a pdf. My computer will NOT refrain from munging the link. Horribly. Please try the google search if you want full validation and research history.
  11. Aug 7, 2016 #10


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    It is unlikely that evolution directly acted to select nausea from dizziness and vertigo as one of its products. It's much more likely that nausea is simply a side effect of how complicated mammalian bodies are, and the downsides of vertigo and dizziness were not enough of a detriment for evolution to select against them except in those individuals who get vertigo or dizziness from even small motions or heights.
  12. Aug 7, 2016 #11


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    Unfortunately I can't remember the source, but here goes.

    Several months ago I ran across an article stating that the first symptom of some common plant poisons disrupts the positional sensing of the inner ear, causing vertigo. Evolution supposedly selected for nausea/vomitting to rapidly clear this rather lethal poison. I know, not very convincing as stated, but the original article was.
  13. Aug 7, 2016 #12

    Fervent Freyja

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    Nausea with vertigo and dizziness, which are both symptoms of stroke, heart attack, and other serious conditions, is likely a warning that forces a person to take it easy and sit, just as it incapacitates when it occurs for other reasons. If nausea didn't occur with some conditions, then we would attempt to carry on as normal, which we know is detrimental to recovery outcomes.


    I doubt you will get a technical answer to your question. I can say that there is an advantage for sickness symptoms in general. Loss of appetite and fatigue in mammals helps divert energy for recovery (carrying on about as normal and digestion requires a lot of energy).
  14. Aug 8, 2016 #13
    I will read up on it! Thanks.
  15. Aug 8, 2016 #14
    I didn't mention fear of heights, just different states to which the brain reacts with vertigo/dizziness. I agree that it seems like a learned behaviour; and as many of us also know it can be unlearned to some degree.
  16. Aug 8, 2016 #15
    I don't see any mention about a specific condition that results in vertigo.
    Commonly, vertigo is used to refer to fear of heights, but that fear has its own term.

    Fear of heights to the extreme is acrophobia - the extreme part is most likely learned.
    Vertigo is the sensation of spinning when you are not, An associated moving in space can also manifest.
    Someone with a fear of heights can feel vertigo.

    At the edge of a cliff, the open space below can also trigger a feeling of being pulled towards it in some individuals.
    The range of a healthy head for heights lets people walk of level ground, a railroad track, or a syscraper beam with indifference.
  17. Aug 8, 2016 #16
    What do you mean by learn and not innate?
    Depth perception and locomotion seem to be the drivers for avoidance of heights. As the infant mammal matures so does depth perception, and the ability to move around freely.
  18. Aug 8, 2016 #17

    jim mcnamara

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    1. this is psychology - an inherently fuzzy discipline, IMO. The discipline has gotten better on this score since I had a few undergraduate classes.
    You can cite lots of references, I went with the mainstream POV. Visual cliff was a 1960 experiment. Basically this paper is what you cited. Okay.
    Consider the possibility that interpretations by professionals in the field are different now. Consider reading the NYU paper.

    2. 'innate' means that one one or more alleles that code for a trait, like the concept of a hardwired response. (best term I could think of). Fear induced by height is not a completely hardwired response. It is both cultural and learned. That is what the takeaway from the NYU citation says.

    Consider the consequences of your presumption -
    Why do 4 year-olds climb into a gorilla enclosure at the zoo? Why do the guys in phinds' picture not all vomit? Why do people sky dive or bungee jump?
    The four year-old did not go to counseling to overcome fear of large animals.

    I should know better than to get into threads like this one. I have nothing more to say in this thread.
  19. Aug 8, 2016 #18
    thanks. I think that explains what it ( innate ) means currently, going beyond just observing behavior. The 60's and all their behavorial experiments had great expectations.
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