Talk:Scotoma

Latest comment: 7 years ago by IamNotU in topic Contradiction issue

Images

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I'm not really sure the "illustrations" of scotoma are entirely appropriate. Typically a scotoma won't appear as a black hole or a hole of any kind, as is the case with the natural blind spot as well as scotoma caused by damage to the brain, but as a region of assumptive information that is generally easy to define. The blind spot lies away from our center of vision and is thus impossible to "focus" on and determine where the edges lie, but larger scotoma and or those closer to the center of the eye can be drawn out (by the patient) with high precision when looking at a particularly difficult to "assume" pattern or moving image. Thus the whole "blurry edges" thing is a little bit silly, the shapes and colors simply continue often making it difficult to tell where it starts and ends.

One thing I can suggest as an illustration of life with scotoma would be a picture of a person with their head apparently missing, and the pattern of the wall or object behind where their head should be seemingly filling the space. It applies not only to people with scotoma but can also be done easily aiming your blind spot. 219.102.220.90 (talk) 06:28, 17 December 2008 (UTC)Reply

Also, peripheral vision is less acurate and contains less colourinformation, meaning it is mostly grey. This is not really depicted in these images. --Docvalium (talk) 18:27, 14 May 2012 (UTC)Reply

Compensation/Interpolation?

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Is the phrase, "The visual signals that are absent in one eye are sent to the cortex by signals from the other eye" accurate? I believe that the brain does a sort of interpolation of the missing information. If the signals from the other eye were necessary to complete the picture, then it would be possible to see a black area in one eye by simply covering the other eye. —Preceding unsigned comment added by 87.160.115.52 (talk) 13:51, 25 February 2009 (UTC)Reply

Absence of visual perception is not the same as black and therefore the illustrations are misleading. But it is difficult to represent nonperception in a still picture, just as it is difficult to represent scintillation in a still picture. Greensburger (talk) 16:05, 25 February 2009 (UTC)Reply

The above sections correctly query the 'illustrations' of scotoma. They, and some of the text gave a very misinformed representation of a patient's 'awareness' of a scotoma. The original images have been replaced with more informative ones and the text changed, with citations added.QuietJohn (talk) 05:10, 24 April 2014 (UTC)Reply

Transient scotoma with positional hypotension?

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Would the term scotoma apply to the "closing in of the world" or collapsing tunnel vision effect caused by the near-fainting experience associated (in some people) with standing up too fast? Or is there another more appropriate term? If so, what? Jornadigan (talk) 13:45, 4 November 2010 (UTC)Reply

Plagiarism?

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some of the Causes section is word-for-word from the text in the website http://www.eyehealth.com/scotoma.html. Is this permissible?QuietJohn (talk) 05:15, 24 April 2014 (UTC)Reply

That page no longer exists, but I checked on archive.org, and actually the text on that page appears to have been plagiarized from Wikipedia. That happens a lot. IamNotU (talk) 21:29, 29 June 2017 (UTC)Reply

Contradiction issue

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It isn't clear what the claimed contradiction is at the end of the first sentence of the Presentation of pathological scotoma section. It appears to be related to a comment in the Visual Cortex#Current_research page which states... "Lesions to primary visual cortex usually lead to a scotoma, or hole in the visual field. Note that patients with scotomas are often able to make use of visual information presented to their scotomas, despite being unable to consciously perceive it". Both statements suggest that visual cortex lesions result in scotoma. Is there another issue?QuietJohn (talk) 05:20, 29 May 2014 (UTC)Reply

I agree that there is no apparent contradiction, so I've removed the tag. IamNotU (talk) 21:33, 29 June 2017 (UTC)Reply

Removed this

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Because all human cognitive schemas are necessarily conceptual models and thus to some extent oversimplified, and because interpersonal variations are natural, it could be that some people's schemas are more simplistic (offering higher distortion) than others', so that, for example, people who perceive improved race relations as equivalent to a postracial society, or social mobility as equivalent to the nonexistence of social classes, have poor appreciation for map-territory discrepancies because their cognitive schemas, as especially oversimplified conceptual models, lack nodes for the representation of some aspects of reality's complexity.

This seems to be trying to elevate an abstruse and debatable political point (whose ultimate intention is shielded, yet obvious) to the level of fact, so that its denial can then be pathologized as a medical condition. This would be fine if it were a report on real-life debate in books and journals. But without documentation, it looks like home-made philosophy. Which one might sympathize with, but not under this banner.

The paragraph that's left is a bit unfocused and weak, being without examples, specifics, or references. From a purely encyclopedic point of view, it could be removed, although it is not as objectionable as what I did remove. It's too bad, because the notion of "intellectual scotoma" is interesting. Let's have some quotes, authors, and books. 178.38.47.245 (talk) 09:17, 28 June 2015 (UTC)Reply