What we call mental illness today may have, at one point, been integral to the evolution of the human brain or human beings in general. That's what several recent studies suggest when their findings are taken together. Research has definitively shown for years that autistic people can commonly display inordinately good memory, an affinity for mathematics, an artistic talent or any number of other bizarrely acute skills. A sizable contingent of people also shows autistic traits without actually being diagnosed as autistic. For that matter, schizophrenia has been found to be a possible side effect of our own sophisticated evolution, and the fact that autism or its characteristics show up exponentially more frequently than schizophrenia in the global population bears significance.
Schizophrenia, mind you, affects only around one percent of Americans, characterized by hallmark symptoms like hallucinations, delusions, confused speech and general lack of control over thought. The symptoms usually start to manifest between ages 16 and 30, and their onset is gradual, slowly increasing in severity. Men are known to be more susceptible than women, and some schizophrenia patients actually start to harm themselves and become violent. Some researchers pontificate that schizophrenia is a latent condition that gets triggered by an event that occurs in a person's life within the aforementioned age range. These days, at least, there's adequate medication for managing and treating it, and administration of said medication, as well as its manufacture, is informed by a superior comprehension of the complex neurology thereof.
According to an October 2017 study, 79 percent of schizophrenia's origin is genetically determined. More recently, a new study published by Australian scientists in NPJ Schizophrenia shows a genetic pathway to schizophrenia and finds it to consist of 97 genes that correlate with genetic shifts in the brain region where schizophrenia is most observable. These findings support an age-old theory that schizophrenia could be an evolutionary side effect. Experts from the Florey Institute for Neuroscience and Mental Health, which is based in Parkville, Australia, argue that their findings here and now bolster those of a 2008 study published in Genome Biology, which basically stated that the brain eventually evolved to a point at which no further evolution could improve cognitive capability, which yielded an increase in metabolic processes that now sometimes err as psychiatric conditions including but not exclusive to schizophrenia.
A co-author on the new study, named in an impossible stroke of irony Professor Brain Dean, said, "Though this is not fully understood, our data suggests the frontal area of the brain is severely affected by such changes," referring to 566 genetic changes discovered in the very regions of the brain that exhibit schizophrenic traits. "There is the argument that schizophrenia is an unwanted side effect of developing a complex human brain and our findings seem to support that argument." So, if schizophrenia marks the overstep of our brain's evolution, could autism be the attempt to circumvent this evolutionary obstacle?
The autism spectrum is known for enhancing normal human abilities and proclivities at the expense of social skills, to say the least, but it's important to note that current research shows that many people who aren't diagnosed with autism exhibit autistic traits. Some of them might be diagnosed as such if they were tested, but some of them might not be. They're unaware of their proximity to the spectrum, and they often consider their unique traits an advantage. It's becoming an increasingly accepted idea that we are all, in fact, on the autism spectrum to some extent. Genetic research supports this, showing that autistic traits have been part of the active human genome for a very long time.
Studies show certain autism genes in the primate genome as well, believed to predate the yet-to-be-understood bifurcation that yielded the human branch. Autism genes have been dated as being arguably over 100,000 years old, and studies suggest they're exponentially more hereditary than schizophrenia genes. Even though a third of autism cases are chalked up to spontaneous mutations, autism typically shows frequent recurrence in certain families. This suggests that autism actually has an evolutionary purpose and is being selected — naturally.
Vitamin D was scarcely understood until the 1990s, but since then, we've been learning a great deal about it, including its pertinence to brain development. A new animal study published on March 20 links the amount of vitamin D in a mother's diet to her child's behavior. Lots of clinical trials have illustrated a correlation between vitamin D deficiency during pregnancy and specifically the birth of an autistic child. This finding has been proven in studies from more than one country. One study even showed newborn babies growing up to develop autism after their mothers were found to be vitamin D deficient and compared them to siblings didn't develop autism.
[researchpaper 리서치페이퍼=Cedric Dent 기자]