January 27, 2012
Intellectual Interests Genetically Predetermined?
Does depression help people do art? Does autism help people do science? Does the normal mind without enough of either come up short in creativity? Not sure. But relatives of those with depression have different intellectual interests than relatives of those who have autism.
A hallmark of the individual is the cultivation of personal interests, but for some people, their intellectual pursuits might actually be genetically predetermined. Survey results published by Princeton University researchers in the journal PLoS ONE suggest that a family history of psychiatric conditions such as autism and depression could influence the subjects a person finds engaging.
Although preliminary, the findings provide a new look at the oft-studied link between psychiatric conditions and aptitude in the arts or sciences. While previous studies have explored this link by focusing on highly creative individuals or a person's occupation, the Princeton research indicates that the influence of familial neuropsychiatric traits on personal interests is apparently independent of a person's talent or career path, and could help form a person's basic preferences and personality.
Princeton researchers surveyed nearly 1,100 students from the University's Class of 2014 early in their freshman year to learn which major they would choose based on their intellectual interests. The students were then asked to indicate the incidence of mood disorders, substance abuse or autism spectrum disorder (ASD) in their family, including parents, siblings and grandparents.
Students interested in pursuing a major in the humanities or social sciences were twice as likely to report that a family member had a mood disorder or a problem with substance abuse. Students with an interest in science and technical majors, on the other hand, were three times more likely to report a sibling with an ASD, a range of developmental disorders that includes autism and Asperger syndrome.
I suspect moderate doses of genes for autism make the mind much more capable of handling the rigor required to do math and science. The "normal" human mind is not as well suited to understand the world scientifically.
What I wonder: does maladaptive autism exist further out on a spectrum from adaptive autistic traits? Or is maladaptive autism caused by other genetic variants beyond those that cause more adaptive forms of altruism?
Here's the abstract and full paper.
From personality to neuropsychiatric disorders, individual differences in brain function are known to have a strong heritable component. Here we report that between close relatives, a variety of neuropsychiatric disorders covary strongly with intellectual interests. We surveyed an entire class of high-functioning young adults at an elite university for prospective major, familial incidence of neuropsychiatric disorders, and demographic and attitudinal questions. Students aspiring to technical majors (science/mathematics/engineering) were more likely than other students to report a sibling with an autism spectrum disorder (p = 0.037). Conversely, students interested in the humanities were more likely to report a family member with major depressive disorder (p = 8.8×10−4), bipolar disorder (p = 0.027), or substance abuse problems (p = 1.9×10−6). A combined PREdisposition for Subject MattEr (PRESUME) score based on these disorders was strongly predictive of subject matter interests (p = 9.6×10−8). Our results suggest that shared genetic (and perhaps environmental) factors may both predispose for heritable neuropsychiatric disorders and influence the development of intellectual interests.
Since genetic sequencing costs have crashed over the the last decade and especially in the last few years we are about to get the flood of DNA sequencing data needed to identify large numbers of genetic variants that contribute to cognitive traits. The picture will be much much clearer in just 4 or 5 years. I'm awaiting the discoveries with great interest.
Alternatively, perhaps siblings who grow up in the same household influence and groom each other's interests through the ordinary mechanisms of human interaction.
In which case there would be zero predictive capacity for the results of the tests they ran. In other words, what you're saying is a valid concern, but "drops out of the equation," as it would only *reinforce* the hypothesis, with autism-related families more likely to condition technical studies, and depression-related families the humanities.
I have known a number of people with a general humanities inclination who could not function up to academic rigor simply because they couldn't bear to spend all day inside at a desk or table, and had to be out "doing things." Just like surviving long bouts of poor weather w/o going stir-crazy, it's definitely conceivable that small amounts of depression could be adaptive, just like mild amounts of autism.
Check the text for a case in which you wrote "altruism" instead of "autism."
How long before we will be able to monitor our epigenome in real time, against our personal optimal benchmark?
We Homo sapiens are blithely sailing into uncharted waters with our eyes closed, at night, and in thick fog.
I like it.
What happens when someone comes from a family that has both?
Both my mother and my grandfather are asperger's cases, undiagnosed mind you, but oh so many of the traits are there. My grandfather was a rocket scientist (literally) and my mother was an accountant. My father, a talented writer and musically minded person, has no trace of any autism spectrum issues that I can see.
My sister is artistically minded. She can write like Earnest Hemingway and paint like Picasso. Math and related subjects however, are very difficult for her. She's on the left politically.
I'm very scientifically minded. I'm not going to toot my own horn here, but lets just say there are things I'm preternaturally talented at in this area that many people have trouble with. I seem to take after my mother and grandfather. I'm politically libertarian (Not a Ronulan).
As for mood disorders and drug issues, there are none in my immediate family tree on either side that I'm aware of.
It should come as no surprise to anyone that talents, inclinations and even fundamental character are highly inheritable. Human beings are not blank slates upon birth to be shaped and defined by environment and experience. We come into this world predefined. Experience and environment influence the people we grow to be, but they do not alter our fundamental nature, only how our nature is expressed.
"I'm politically libertarian"
That's just normal intelligence at work.
"What I wonder: does maladaptive autism exist further out on a spectrum from adaptive autistic traits? Or is maladaptive autism caused by other genetic variants beyond those that cause more adaptive forms of altruism?"
Few on the spectrum have all of the now 25 gene differences that are associated with ASDs. Those that have just enough to make them Aspies may well marry, and produce some portion of their children with a combination of their differences that are then sufficient to make those children auties much farther down the spectrum than their parents. These children may well have fewer social abilities, as well as other problems, like dyspraxia, alimentary dysfunctions, and severe sensory perception issues.
It is notable that the spectrum of "maladaptive autism" shifted substantially when the industrial revolution began. Those who could not socialize enough to help out in a farm village could often work quite well in many of the jobs in industrial society. When demands for intense attention are high, and demands for social interaction are low, more of the spectrum becomes adaptive. When demands for social interaction grow, and demands for intense attention and pattern recognition are lowered, then the adaptive abilities of those with any given level of autism are decreased. This is happening right now, because of a flood of more highly competent communicators, women, who expect others to make them comfortable by being like them. Women have now entered the workplace sufficiently that we see workplace adaptation to their needs/desires in the last 15 years. Railing against it is useless, besides immoral.
Does having family members who are depressed morons cause people to become second rate social scientists who do meaningless studies that rely on people to subjectively self-identify between two poorly framed choices of personality types? The answer from this paper is, apparently, yes.
The researchers also assume that the students know all the psychiatric conditions among their close family members. Some may misidentify what problems their close blood relatives may have. Others may not know the family secrets. Without knowing more, it appears that the study is weak in execution.
So, are kids from families with histories of both depression and autism more inclined to be polymaths?