Wednesday, June 21, 2017

SearchResearch Challenge (6/21/17): Seeing things?


Seeing is complicated and subtle.  


Of course, it works really well most of the time.  We see colors, textures, print, cats, people, silver moonlight on the river, smiles, and that expression from your beloved.  

But sometimes vision gets more complicated than we'd like.  This is our topic for this week--When you see things, what's going on (and how concerned should you be)?  



These three Challenges really happened to me, so I am, naturally, very curious about what you'll discover!  

1.  When I went for a run a while ago, I scampered around a blind corner and smashed my forehead into a stop sign.  The impact didn't hurt much, but it dropped me flat on my back onto the sidewalk.  I got up quickly and resumed running.  Nothing was hurt, BUT this is what my visual field looked like: 


There was a relatively large C-shaped fuzzy spot just to the left of my visual center.  I fell on my back, so my eyes were untouched by the accident.  The good news is that this fuzziness went away on its own after about 1 hour.  Challenge:  WHAT is this visual disruption called?  Should I worry about it? 

2.  Unrelated to Challenge #1, I noticed recently that whenever I look up into a clear blue sky (or at a blank white wall) I see lots of small circles and a few "threads" kind of wandering around.  They're not big enough to obscure anything, and I don't notice them during the ordinary course of the date... but they're kind of odd.  Again, WHAT are these things called?  Should I worry about them?  

3.  Unrelated to #1 or #2:  Even though I have lots of experience seeing the world, I also noticed that when I close my eyes for a second and then look downward rapidly without opening my eyes, I see a fairly large circle appear and then disappear in a couple of seconds.  I'm surprised I've never noticed this before, but I have no idea what this visual effect is called or what causes it!  Can you tell me?  (And let us know if you see this circle appearing when you look down with closed eyes.)  


Let us know what you figure out... let's SEE if you can answer my Challenges! 

As always, let us know what you discover--and just as importantly, HOW you found out what you did.  

Search on! 


9 comments:

  1. Hello Dr. Russell and everyone


    1. What is this visual disruption called? Should I worry about it?

    [c shaped fuzzy vision] then Google suggested [c shaped blurry spot in vision] and ["c shaped" blurry spot left vision]

    Possible answers: Floaters or Migraine Aura

    [big "c shaped" temporary blurry spot vision]

    When no headache occurs, it is called a visual or ophthalmic migraine.

    [ophthalmic migraine]

    Ocular Migraine

    [ocular migraine c shape] no so good because confirmation bias

    Video: Migraine aura Couldn’t watch video because no supported on my lap. “This visual aura may expand into a sickle- or C-shaped object, with zigzag lines on the leading edge. As it moves, it may appear to grow. Auras aren't the same for everyone, so you might also experience bright spots or flashes. Auras are sometimes accompanied by a partial loss of vision referred to as a scotoma. Auras commonly last 10 to 30 minutes.”

    Answer: Ophthalmic migraine. Reading says is something not to worry. And, I think it is better to check with a doctor because of the impact and more if you don’t have migraines.

    2. What are these things called? Should I worry about them?

    [small circles when looking sky]

    Spots, Dots, and Floaters: Seeing What's Inside Your Eye

    Today I Found Out: WHAT CAUSES “EYE FLOATERS” Besides why this happens, mentions: The perception of eye floaters is known as myodesopsia….Eye floaters are examples of entoptic phenomena. Entoptic phenomena are things we see where the source is within the eye itself...If you ever see a ton of floaters appear out of nowhere, possibly with some light flashes, you should get to an eye doctor immediately

    [Eye floaters]

    Mayo Clinic: Most don’t need treatment.

    They are called: Eye Floaters. You don’t need to worry, except if you suffer the case mentioned up.

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    Replies
    1. Ramón, that was an interesting video you found - did a couple screen grabs from it… very similar effect to what Dan illustrated…
      from the Mayo Clinic video you found
      migraine aura manifesting in the visual cortex
      "The best known visual aura is called a fortification spectrum because its pattern resembles the walls of a medieval fort. It may start as a small hole of light or sometimes as bright geometrical lines and shapes in your visual field."
      Scotoma
      searched visual cortex damage…
      wiki info
      American Foundation for the Blind
      damage SERP
      location SERP
      perhaps Dan struck the back of his head after the STOP sign flattened him?
      caveat - it is often unwise to play internet MD (sometimes referred to as Dr. Google) or medical advisor… too many variables, poor decisions/interpretations & unintended outcomes.

      Delete
    2. Agree with you about unwise to play internet MD. Luckily, I'm just looking for the name of this visual phenomenon. No treatment recommendations required!

      Delete
    3. Hello Dr. Russell and Remmij. I agree with both of you.

      Thanks, Remmij for the screen grabs and for sharing about Scotoma. And for the links (I like to read and learn with your sharings) and your images. Also the Apple catch is impressive

      Delete
    4. Reading Remmij’s comment:

      [why scotoma is c shaped][

      Scintillating scotoma was first described by 19th-century physician Hubert Airy...


      3. What this visual effect is called or what causes it! Can you tell me?

      [circle looking down eyes closed]

      Two articles mention: They can be a form of phosphene. Also Google suggested searches mention it.

      This is called a phosphene — the experience of perceiving light in the visual cortex without light actually entering the eye.

      [Phosphene] Fosfeno in Spanish

      These strange blobs you see have a name; they’re called “phosphenes,” and researchers believe that actual light may play a role. But not ordinary light — this light comes from inside your eyes. In the same way that fireflies and deep-sea creatures can glow, cells within our eyes emit biophotons, or biologically produced light particles.”...Depending on where a phosphene originates, it can take on a variety of shapes, patterns and colors….In the 1950s, the German researcher Max Knoll: 15 categories…

      [closing eyes looking down fast circles]

      Why Do I See Patterns When I Close My Eyes?

      WHAT THE THINGS YOU SEE WHEN YOU RUB YOUR EYES ARE CALLED


      Delete
  2. Replies
    1. Great catch. Yes, in fact this DID happen when I worked at Apple. (Nice deduction from the Cupertino photo! At the time my office was at Infinite Loop 1, so I was running from there.)

      Delete
  3. ooops – forgot the evidence of Dan's sign mishap…
    the chalk outline
    (fwiw, any head injury that causes a fall or blackout
    should be checked out… had a brother-in-law that just delayed having an accident checked out…
    has a ruptured ear drum and now a bad ear infection from a blow to the head that knocked him out…
    classic comedy situation… a rake handle… tried not to laugh)
    something like this… without the repetition…
    "impulsive force"

    ReplyDelete