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Medical When (and Why) Does a Human Baby's Vision "Flip"

  1. Mar 2, 2017 #1
    Greetings to all,
    I realize that there is another "dead thread" about this subject (with a lot of interesting comments) but I think I can add a "new dimension" to the conversation.:smile: I have also put this question out on a few other Science Forums....

    The human eye is much like the lens of a camera, telescope or microscope. An image, as it passes through the lens, is projected onto the retina upside down and backwards. It is the brain's job to sort out and make sense of the image entering through the eye.

    Most doctors agree that newborn babies see everything upside down for a "period of time" - but no one really knows for how long. Since gravity determines "up" and "down", wouldn't the baby have to be able to at least hold it's head up to begin to sort things out? And wouldn't left and right logically follow after that?

    Teacherman
     
  2. jcsd
  3. Mar 2, 2017 #2

    Ygggdrasil

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    What would be the evidence for this claim? How can you tell whether a baby perceives the world upside down? Perhaps they have just not learned the concepts of up and down yet.
     
  4. Mar 2, 2017 #3

    jim mcnamara

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    With the exception of mathematical logic, applying logic based on common sense does not always work in Biological Science. What seems to be common sense may be completely wrong.

    The answer to your question: I do not know completely. I do know: currently, there is no science to back up the claim.

    A partial answer lives in the following description.
    Babies have a huge number of synapses (neural connections/junctions), more than adults have. Human cognitive and motor development involves reinforcing some of those connections and losing others that are not used. Neural plasticity is the term you will see.

    For example, it is known that all infants can hear any of the phonemes in any human language. Think of it as preprogramming. Over time and exposure to language sounds around the maturing infant, the ability to perceive "unused" phonemes deteriorates. The "program" is becoming much more efficient. By 24 months some sounds are fully lost.

    This is demonstrated by the fact that adults learning a foreign language often results in speaking the new language with an 'accent' as far native speakers are concerned. One big reason is because a few of the new language sounds are "missing", cannot be reproduced correctly by the new speaker.

    I would submit this phenomenon has more to do with your question than anything else. Do cerebral palsy victims who cannot raise their heads until much later in life have upside down vision much later in life? That answer might be a path to understanding.

    This popular science version: http://www.pregmed.org/baby-developmental-milestones/when-can-babies-see
    indicates there is no research to support 'upside down' vision. That means that to a large extent this discussion is kind of an empty exercise.

    I think the idea comes from this clinical study discussion: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2585817/
     
  5. Mar 2, 2017 #4
    Thanks for your response, Yggg,
    Teacherman
    Let's start with this video:
     
  6. Mar 2, 2017 #5

    sophiecentaur

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    Along with several other contributors to this thread, I would doubt that. For a start, "most doctors" haven't been able to study this in any depth at all and, in any case, the frame of a casual observer would have more to contribute to any conclusion than any actual effect in the child's vision. More likely there is just confusion in the mapping of the image projected on the retina with the 'World Map' that's established in the brain. When I read statements like the above, I always ask myself "what could be the possible evolutionary advantage in a baby 'seeing things' upside down?"
    If there are such advantages in reading and writing 'upside down' then why don't we all do it that way from the start? The direction of writing (left right / up down) varies over the different different languages of the world. Are some inherently better for reading?
    The reason that upside down writing works for some kids with a reading problem is most likely because they have developed initial problems or hang ups with the conventional presentation and they benefit from a re-start to the learning process. (Turn it off and turn it on again works for computers)
     
  7. Mar 3, 2017 #6

    mfb

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    As there is no evidence that babies have inverted vision, the thread has been split. The general inverted vision discussion is now here, this thread is closed.
     
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