My big fat brain

The myth of the overgrown autistic prefrontal cortex

One of the most-quoted “facts” about autism I come across is the idea that autistic children have “excess” neurons in their prefrontal cortex, and that their brains weigh an “excess”’ amount.

But where does this idea come from?

Would you believe it came from analyzing the autopsies of the brains of 13 children—only seven of whom were autistic?

I don’t understand how that passes muster.

In Neuron number and size in prefrontal cortex of children with autism (Journal of the American Medical Association, Nov. 9, 2011), researchers at the University of California, San Diego analyzed autopsy results of 13 boys aged 2–16 who died from 2002 to 2006. They concluded that the prefrontal cortex (PFC) of the autistic boys had an abnormal “excess” number of neuron counts, and of brain weight overall.

Note that the title says “children with autism.” Even though it ought to say, instead, “boys with autism.”

Better still, rather than children with autism, the title should refer to what was actually studied: a number so small from an age range so wide that surely nothing whatever about autism or anything else can be concluded from these results.

In this study, we have to decipher language like: “Children with autism had 67% more neurons in the PFC [prefrontal cortex] … compared with control children. … Conclusion: In this small preliminary study, brain overgrowth in males with autism involved an abnormal excess number of neurons in the PFC,”, which is so contradictory and confusing as to muddle any actual findings that might shed light enough to benefit those with autistic brains. If there were any there at all.

“Small” preliminary study? If a sample size of seven is what these researchers consider “small,” then how would they characterize an even dozen? A multitude?

According to the 2022 US Census, 22.2% of the US population is under 18—or about 74 million kids. 

According to the National Institutes for Health, 23 in 1000 children in the US are autistic. Assuming that the NIH is counting children as anyone under 18, that’s nearly 1.7 million autistic children in the US.

And how many autistic children did these brainiacs looks at?

I’ll say it again, because it’s so absurd.

Seven.

They studied the autopsied brains of seven autistic boys, and had the nerve to draw conclusions from that.

And people are foolish enough to cite them. Over and over.

How did this study of seven autistic and six control boys in age ranging from 2 to 16 out of approximately 1.6 million children of that age come to be regarded by the CDC as an important source of information about autistic brains? And not just the CDC, but a plethora of non-autistic “experts” on YouTube disseminate this misleading information, referring to the excessive firing or overgrowth of cells in the frontal lobes of autistic children. They parrot the study as though it means something. 

And what about the brains of autistic girls? What can this study tell us about that? That is, beyond the fact that they are not included.

In Neurodivergent brains are like the wild west, I bring attention to the fact that I and those like me have a significantly different neurological makeup than the majority of the population, the neurodominant. Not only are autistic brains different from those of the neurodominant—they are also very different from one another. You could say that the one true thing that autistic brains do have in common is that they have nothing in common with either each other or typical brains. 

With that in mind, what can seven autistic brains possibly tell us?