In my 2024 post "UK Biobank Study of Thousands of Brains Finds Negligible Correlation Between Brain Size and Intelligence," I discussed a study analyzing 7000 people who had both brain scans and also a group of written tests of intelligence. The study is entitled "Structural brain imaging correlates of general intelligence in UK," and you can read it here. The study found a correlation of only .276 between brain volume and intelligence, and a correlation of only .281 between gray matter volume and intelligence.
How high a correlation is that? In the scientific paper entitled, “A guide to appropriate use of Correlation coefficient in medical research,” we have a Table 1 which has the heading of "Rule of Thumb for Interpreting the Size of a Correlation Coefficient." Here is that table:
| Size of Correlation | Interpretation |
| .90 to 1.00 (−.90 to −1.00) | Very high positive (negative) correlation |
| .70 to .90 (−.70 to −.90) | High positive (negative) correlation |
| .50 to .70 (−.50 to −.70) | Moderate positive (negative) correlation |
| .30 to .50 (−.30 to −.50) | Low positive (negative) correlation |
| .00 to .30 (.00 to −.30) | negligible correlation |
So by finding a correlation of only .276 between brain volume and intelligence, the UK Biobank study with a very big sample size of about 7,000 subjects has found only a negligible correlation between brain size and intelligence. And by finding a correlation of only .281 between gray matter volume and intelligence, the study with a very big sample size of about 7,000 subjects has found only a negligible correlation between gray matter volume and intelligence.
How has the incredibly stubborn belief community of neuroscientists responded to this important study so relevant to the "brains make minds" claims they like to make? Such neuroscientists have tended to either ignore or misrepresent this study. We have an example in a recent scientific paper entitled "Neurite density but not myelination of specific fiber tracts links polygenic scores to general intelligence." You can read it here.
The paper states this: "It is a well-established finding that bigger brains are associated with higher levels of intelligence [26,148,149] and a common explanation for this phenomenon is that individuals with more cortical volume are likely to have a higher number of neurons [150]." We have here an untrue claim citing papers that do not establish any such finding that "bigger brains are associated with higher levels of intelligence." The largest of the three studies mentioned above (with numbers of 26, 148 and 149) is reference 26, which is a reference to the very paper discussed at the top of this post: the paper "Structural brain imaging correlates of general intelligence in UK" that you can read it here. The study found a correlation of only .276 between brain volume and intelligence, and a correlation of only .281 between gray matter volume and intelligence.
What happened here is that a study finding only a negligible correlation of intelligence and brain volume is being cited as if it was a study finding a good correlation of intelligence and brain volume. The bad citation here is as bad as someone falsely claiming that cigarettes are healthy to smoke, while citing as his evidence a paper finding that smoking cigarettes causes cancer.
This type of citation misrepresentation goes on all the time in the bungling world of today's neuroscience. It seems that a large fraction or a majority of neuroscience papers are guilty of making some untrue claim, and citing some other paper as their evidence, when the paper cited does not actually provide decent evidence for the untrue claim.
There are two main types of ways that such citation errors occur in neuroscience papers:
(1) A neuroscience study may incorrectly cite a high-quality paper, acting as if it establishes some claim the paper did not actually make. The example I give above is an example of this type of thing.
(2) A neuroscience study may incorrectly cite a low-quality paper that claimed or insinuated some thing but failed to support such a claim with any good evidence.
In my post here I documented how the second category of such errors went on in a particular neuroscience paper. Here is a quote from that post:
"So let's summarize what has gone on in this crucial part of the 'Essence of the Engram' paper. The authors have made the claim that there is a 'substantial body of evidence' for engrams, and have cited five different papers as references. Not one of those papers presents any robust original research supporting claims that engrams exist. The first four papers cited are low-quality science studies that failed in numerous ways to be good experimental science. The fifth paper is co-authored by the co-author of several of these low-quality science studies, and presents no new research. This is what goes on all the time in literature referring to engrams. You have either papers presenting low-quality science experiments, or you have papers that refer to low-quality science experiments. Nowhere will you find any solid research presenting any robust evidence for engrams.""
Inappropriate citation is when some scientific paper cites some other paper as support for some claim, when the paper does not actually support such a claim. A scientific paper entitled "Quotation errors in general science journals" tried to figure out how common such misleading citations are in science papers. It found that such erroneous citations are not at all rare. Examining 250 randomly selected citations, the paper found an error rate of 25%.
We can reasonably suspect a sleazy "old boy network" at work here, in which Professor X has lots of professors he has encouraged to cite his papers (regardless of whether the citation is appropriate), with the understanding that such a favor will be reciprocated by that professor citing the papers of those professors (regardless of whether such citations are appropriate).
We read here, "According to one estimate, only 20 per cent of papers cited have actually been read." Clearly there is a gigantic amount of sleazy citation going on the sake of artificially ballooning citation counts.
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