One of the strongest challenges to claims that brains make minds came from the research decades ago of the physician John Lorber. Lorber studied many human patients with hydrocephalus, in which healthy brain tissue is gradually replaced by a watery fluid. Lorber's research is described in this interesting scientific paper. A mathematics student with an IQ of 130 and a verbal IQ of 140 was found to have “virtually no brain.” His vision was apparently perfect except for a refraction error, even though he had no visual cortex (the part of the brain involved in sight perception).
In the paper we are told that of about 16 patients Lorber classified as having extreme hydrocephalus (with 90% of the area inside the cranium replaced with spinal fluid), half of them had an IQ of 100 or more. The article mentions 16 patients, but the number with extreme hydrocephalus was actually 60, as this article states, using information from this original source that mentions about 10 percent of a group of 600. So the actual number of these people with tiny brains and above-average intelligence was about 30. The paper states:
"[Lorber] described a woman with an extreme degree of hydrocephalus showing 'virtually no cerebral mantle' who had an IQ of 118, a girl aged 5 who had an IQ of 123 despite extreme hydrocephalus, a 7-year-old boy with gross hydrocephalus and an IQ of 128, another young adult with gross hydrocephalus and a verbal IQ of 144, and a nurse and an English teacher who both led normal lives despite gross hydrocephalus."
Believers in the "brains make mind" dogma have sometimes tried to suggest that maybe Lorber was just some erring researcher who got things wrong. But an examination of scientific papers by other authors will produce some results similar to those of Lorber. For example, consider the paper "Intellectual Development in Shunted Hydrocephalic Children," which has its full text hidden behind a paywall. The study examined the intelligence of 200 children who had lost varying amounts of their brain due to the brain-wasting disease of hydrocephalus. The abstract contains no specific numbers on IQ. But we read this:
"The following groups were found to be of normal intelligence: white patients with internal hydrocephalus and with meningomyelocele, and black patients with meningomyelocele and with external hydrocephalus. Intelligence quotient was found to be unrelated either to number of shunt revisions or severity of hydrocephalus prior to initial surgery, but was related to age at initial shunt placement and shunt function. Children with internal hydrocephalus and hydrocephalus with meningomyelocele whose shunts were kept functioning were found to be of normal intelligence."
Here we have a remarkable claim indeed: that there was no relation between IQ and the severity of the devastating brain-wasting disease hydrocephalus. A paper on the same topic is the paper "Psychometric intelligence after infantile hydrocephalus." In this case the full text of the paper is available for free online. The paper tested examined IQ in 48 children who had the brain-wasting disease of hydrocephalus.
The paper gives us the interesting graph below. Each third of the graph shows a different type of IQ measurement.
- 14 of the 48 children could not be tested for intelligence using IQ tests. There are various reasons why brain damage might make someone unsuitable for participating in IQ tests, such as damage that might cripple vision or coordination or speech capabilities. Being unable to participate in an IQ test does not necessarily mean very low intelligence.
- Of the severely brain damaged children who could participate in IQ tests, IQ ranged from 55 to 130, with the average being not far from the average IQ of 100.
- Very notably, 16 out of 34 of the severely brain damaged children who could be tested for verbal IQ scored higher than average for verbal IQ, scoring above 100.
- Four of the severely brain damaged children scored above 115 on the verbal IQ test, with one of these children having a "genius" score on the verbal IQ test, a score higher than 130.
Overall the results of this paper corroborate John Lorber's results. We are left with an anomaly that is very hard or impossible to explain under the "brains make minds" dogma, but easy to explain under the hypothesis that brains do not make minds.
A related study was reported in the Scientific Reports sub-journal of the very prestigious journal Nature, and had the title "Life without a brain: Neuroradiological and behavioral evidence of neuroplasticity necessary to sustain brain function in the face of severe hydrocephalus." The study examined a rat named R222 that had lost almost all of its brain because of a disease caused hydrocephalus, which replaces brain tissue with a watery fluid. The study found that despite the rat having lost almost all of its brain, "Indices of spatial memory and learning across the reported Barnes maze parameters (A) show that R222 (as indicated by the red arrow in the figures) was within the normal range of behavior, compared to the age matched cohort." In other words, the rat with almost no brain seemed to learn and remember as well as a rat with a full brain. The authors stated, "It was not possible from these images of R222 to identify the caudate/putamen, amygdala, or hippocampus." Contrary to the frequently stated but incorrect claim that a hippocampus is crucial for memory, the rat without a hippocampus managed to learn just fine.
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