Talk:Grey matter/Archive 1

Comment
"In addition, grey matter does not have a myelin sheath and does not regenerate after injury unlike white matter." Is this true? I thought that new(ish) research indicates that grey matter can regenerate, although it's not certain whether it can connect to the rest of the brain in any meaningful manner. http://healthlink.mcw.edu/article/926345803.html


 * In addition to this, it says earlier in the article that grey matter has "few myelinated axons", and later none. --aciel 19:24, 14 October 2005 (UTC)


 * In addition to this, new research published by Yale university has shown that meditation is associated with an increase in grey matter indicating that grey matter can be grown.

http://www.sciencedaily.com/releases/2005/11/051110215950.htm

The entire paragraph under "function" is full of information that is NOT in the article that it cites as it's source. None of that is in there. The word oxygen appears in that entire study exactly zero times. — Preceding unsigned comment added by 67.55.43.85 (talk) 22:29, 3 November 2014 (UTC)

Sentence removal
I have removed the following sentence/paragraph because it sounds silly. I think a better source is required if one is going to make claims about "intelligence-related" grey or white matter differences between sexes. To the lay reader, this sentence is, at the least, not very well written, and at worst, carries POV connotations—though I don't claim POV is intended. Especially as a paragraph unto itself, with no context, it comes across oddly. (Note: the most recent edit was the "(definitions crucially needed)" segment, which really doesn't belong in the sentence proper.)
 * In general, men have nearly 6.5 times more intelligence-related (definitions crucially needed) grey matter than women, whereas women have nearly 10 times the amount of intelligence-related white matter of men.

Outriggr 22:55, 5 July 2006 (UTC)

Grey matter/gray matter

 * ''Discussion moved from User talk:Arcadian

How did you come to the conclusion the latter was the more common spelling? - Mgm|(talk) 10:21, 12 February 2007 (UTC)
 * I agree that "Gray" and "Grey" are interchangeable when referring to the color. However, the anon was correct in stating that Gray matter is more commonly used than Grey matter. Both of the online medical dictionary links I can find use "gray":, . And two of my three reference books (Netter and BRS/Chung) use "gray" (ironicallly, the one which uses "Grey" is the 2005 edition of "Gray's anatomy for students"). PubMed has 118 hits for "grey matter" and 352 for "gray matter". Currently google usage is roughly equivalent, but I think that much of that is due to mirrors of Wikipedia, which has used the "grey matter" spelling for years. --Arcadian 14:02, 12 February 2007 (UTC)
 * Both titles are heavily linked to within Wikipedia itself. Instead of relying on pubmed or Google, I think we should look at what would cause the least redirects. Unless there's a VERY good reason to move it based on whatlinkshere, I think we should leave the article where it is as per WP:MOS (Use the spelling the article was originally created with). - Mgm|(talk) 10:17, 13 February 2007 (UTC)
 * Either way, the article should be consistent in that whichever term is used as the redirect target (i.e. the article title itself) should be SOLELY employed in the article text. Tomalak Geret&#39;kal (talk) 00:10, 14 December 2008 (UTC)
 * As the guy who has been doing most of the maintenance of neuroscience articles recently, my policy about this is complete indifference. There is a constant low level of people changing between English and American spelling, or changing date formats, and I consider all this far too boring to pay attention to.  So as far as I'm concerned you can change this in any way you want to, as long as the links still work. Looie496 (talk) 01:56, 14 December 2008 (UTC)

Presence of Myelin?
According to "Essential Neuroscience," (2007, Siegel et al, page 140) "The gray matter of the spinal cord contains primarily neuronal cell bodies, dendrites, and myelinated and unmyelinated axons..." The introduction to this article makes it sound like gray matter either contains cell bodies exclusively (which is nonsense to anyone knowledgeable about neuroscience) or does not contain any myelinated axons by contrasting it with white matter. (which is much more likely to trip up anyone moderately knowledgeable, as it did me) The wording should be changed to reflect that white matter has a higher concentration of myelin, but that both white and gray matter contain both myelinated and unmyelinated fibers. —Preceding unsigned comment added by Bobsagat (talk • contribs) 01:44, 8 February 2009 (UTC)
 * I think you're right -- the wording is not wrong, but is hard to understand. If you would like to take a shot at improving it, please go for it. Looie496 (talk) 17:14, 8 February 2009 (UTC)
 * I took a stab at it... I tried to make the changes and keep the sentence structures the same, but I think it's rather awkward. Feel free to clean it up if you wish.Bobsagat 20:39, 8 February 2009 (CST)
 * The aesthetic quality may be marginal, but it looks clear enough, so I'm not going to fool with it. Looie496 (talk) 01:37, 11 February 2009 (UTC)

Seems contrary
I mean, the title is grey matter but the article uses the spelling gray. 108.6.15.59 (talk) 23:52, 23 February 2010 (UTC)
 * One spelling is British, the other American. Every so often people come along and switch them.  I long ago decided that it isn't worth worrying about.  Regards, Looie496 (talk) 22:24, 24 February 2010 (UTC)

Illustration
The illustration on this page which is labeled micrograph of gray matter is the same illustration on the White Matter page and there is labeled micrograph of white matter. So what gives? Anyone else catch this? — Preceding unsigned comment added by Narjis542003 (talk • contribs) 18:44, 21 September 2011 (UTC)
 * The answer is in the image caption: one side of the image shows white, and the other side shows gray. It's not obvious when you first look at the picture, but if you read the caption carefully and then look for what it describes, you'll be able to see what it's talking about. --Tryptofish (talk) 19:35, 21 September 2011 (UTC)

Grey Matter(physics)
I think there should be an article regarding grey matter in terms of physics, I would happy to expand on the topic, but I feel I am in a position to elaborate on my expressions in terms of theory initially. — Preceding unsigned comment added by Davidyevgenyroven (talk • contribs) 01:05, 10 August 2012 (UTC)
 * Anything that goes into a Wikipedia article needs to be based on reputable published sources. If such sources exist, the idea is worth discussing. Looie496 (talk) 01:19, 10 August 2012 (UTC)
 * Adding to what Looie said, you may find it useful to read WP:NOR. --Tryptofish (talk) 15:20, 10 August 2012 (UTC)

Source for effects of child abuse&pornography
There are sources out there that should be able to replace the popular press source, but I currently don't have time to find them. http://www.ncbi.nlm.nih.gov/pubmed/23319445 discusses white-matter effects, but mentions gray matter effects in the intro. I wouldn't necessarily use it for the statement in question, but it might be a place to start looking.

As for the effects of pornography, see WP:MEDRS & WP:NOT for why this shouldn't be mentioned. These studies are very new and have not been summarized by the medical community sufficiently as of today (2014). CFCF (talk · contribs · email) 10:55, 2 June 2014 (UTC)


 * My preference would be to simply remove that material. Stuff like that is WP:UNDUE in an article at this level of generality -- there are zillions of equally significant tidbits of information about gray matter.  Much of it would more appropriately be placed in our article about the human brain, if it belongs anywhere at all. Looie496 (talk) 13:09, 2 June 2014 (UTC)
 * I agree, and I think it's a pretty unambiguous situation, so I removed it (the "R" of WP:BRD). --Tryptofish (talk) 21:37, 2 June 2014 (UTC)

Confusing
As a non neuroscientist, the terminology is unfamiliar to me and prevents, in my opinion, a general understanding of the topic. Emvern (talk) 18:34, 17 November 2014 (UTC)
 * Thanks for your comments,, I have tried to expand and somewhat simplify this article. Please continue to tag other anatomical articles as you pass them by, this is one way of letting future editors know that an article can be simplified. If you feel confident making small changes or simplifications, then I also invite you too to contribute. This article is not perfect and if you could leave some more feedback here I'll see what I can do. Cheers, --Tom (LT) (talk) 06:23, 18 November 2014 (UTC)

picture of brain grey matter
please could someone add one?, e.g. http://www.medinewsdigest.com/wp-content/uploads/2011/12/Brain_Cortex_Harvard.png

from http://multiple-sclerosis-research.blogspot.com/2015/01/education-whats-mri.html?m=1

JCJC777 (talk) 21:23, 31 October 2016 (UTC)

Clinical sourcing
The section about clinical significance relies much too much on primary sources, and in several cases, even on preliminary pilot studies. This is a particularly significant problem because of the health-relatedness of the content. Please see WP:MEDRS. --Tryptofish (talk) 14:37, 1 November 2016 (UTC)
 * @ agree and have removed content, pleased to see when I go to the talk page I am not the only one troubled by this. This reminds me of an issue we have had with gender and race-based anthropometry affecting several other articles. --Tom (LT) (talk) 22:24, 27 January 2017 (UTC)
 * Thanks for doing that. --Tryptofish (talk) 00:48, 28 January 2017 (UTC)

Removal of 'volume' information
I have boldly removed much of the information about brain volume. It is not uncommon for anatomy articles to include pseudo-scientific content that in fact is reflective of social attitudes, and so it is important that reliable sources are used to back up content. See WP:MEDRS for more information. For posterity's sake, the removed content is here: --Tom (LT) (talk) 22:24, 27 January 2017 (UTC)

Congrats you've just made this article anodyne and useless, so people will stop using wiki and look elsewhere. You could at least refer to these sources and make some questioning comment. Sad to see wiki losing it's value and relevance, and obviously demotivating ref spending any future energy adding edits, cheerio JCJC777
 * @ I'm sorry you feel that way. As you would have seen from my edit summaries, I referred to WP:MEDRS. This is a WP:guideline which states that articles making medical claims should be backed up by reliable sources. Here on Wikipedia, that means secondary sources - which are usually reviews or meta-analyses. These are more reliable than primary sources, which as you can imagine (in addition to risks of bias) evaluate only a small population in a certain way in a limited manner. I am not going to stand by while Wikipedia makes claims like poor people, bipolar persons, unhappy people have less grey matter in their brains without adequate sourcing. These claims could, in fact, be wrong, and we are not doing those groups a favour by publicising those claims here. If there are reliable secondary sources, please add them. Wikipedia has a lot of intricacies and I suggest have a chat in future to those at WP:TEAHOUSE who can help you along the way. I am also happy to help in any way I can. Cheers --Tom (LT) (talk) 22:35, 28 January 2017 (UTC)

Cheers Tom, thanks for your good reaction and apologies my outburst. Maybe wiki could have an "interesting but unproven" associated page for each topic, like the talk page. Best @JCJC777

Volume associated with bipolar disorder, and substance misuse
Some structural differences in grey matter may be associated with psychiatric disorders. There was no difference in whole-brain grey matter volume between patients with bipolar I disorder and healthy controls. Subjects with bipolar I disorder had smaller volumes in the left inferior parietal lobule, right superior temporal gyrus, right middle frontal gyrus, and left caudate. Only the volume of the right middle frontal gyrus was correlated with duration of illness and the number of episodes in patients.

It has been found that adolescents suffering from bipolar disorder are more likely to develop substance use disorders if they have lower gray matter volume.

Volume associated with smoking
Older smokers lose grey matter and cognitive function at a greater rate than non-smokers. Chronic smokers who quit during the study lost fewer brain cells and retained better intellectual function than those who continued to smoke.

Researchers discovered less grey matter in brains of men who view pornography in large amounts compared with those who do not. Yet a direct influence of pornographic material on shrinking size of grey matter could not be made. Further studies are urged.

Volume associated with poverty
Numerous reports have shown that children in lower-income families do worse on average on IQ and standardized tests compared to children from wealthier families. Later research has investigated the associations between poverty and neural development. This has shown an association between poverty and lower volume and surface area of grey matter in children growing up in poverty. A U.S. study found that at birth there was no significant difference in total grey matter of newborn babies, but at the age of 2 a significant difference in grey matter was found, and by the age of 4 this difference was further pronounced. Test scores have been linked to atypical structural development in the brain, with children living in poverty having a regional grey matter that was 3-4 percentage points below what was deemed the developmental-norm. Similarly, a 2015 study conducted in the USA compared cortical grey matter of 8th graders in Massachusetts. Children from lower-income families not only scored lower in maths and English in standardised tests, but MRI showed that these children statistically had significantly lower grey matter volume and cortical thickness of the bilateral temporal and occipital lobes, compared to children from higher income families. No significant differences were found in white matter volumes.

Regional differences are not consistent from study to study. For instance, previous research examined prefrontal cortical thickness in healthy children – a region deemed essential to executive function, which is in turn associated with academic success, and has a long developmental trajectory, which may be susceptible to environmental factors. In a sub-sample of cases from a larger pool of 433 subjects, MRI scans showed the right anterior cingulate gyrus and the left frontal gyrus were significantly correlated with poverty.

Volume associated with subjective happiness score
A positive relationship has been found between the volume of grey matter in the right precuneus and the subject's subjective happiness score.

Volume associated with mindfulness
A 6-week mindfulness based intervention was found to correlate with a significant grey matter increase within the precuneus.