Gifted Issues Discussion homepage Forums GT Research Giftedness and Prenatal Exposure to Testosterone

http://www.sciencedaily.com/releases/2011/03/110311153549.htm
Could Giftedness Be Linked to Prenatal Exposure of Higher Levels of Hormones?
Science Daily
March 12, 2011

A longstanding debate as to whether genius is a byproduct of good genes or good environment has an upstart challenger that may take the discussion in an entirely new direction. University of Alberta researcher Marty Mrazik says being bright may be due to an excess level of a natural hormone.

Mrazik, a professor in the Faculty of Education's educational psychology department, and a colleague from Rider University in the U.S., have published a paper in Roeper Review linking giftedness (having an IQ score of 130 or higher) to prenatal exposure of higher levels of testosterone. Mrazik hypothesizes that, in the same way that physical and cognitive deficiencies can be developed in utero, so, too, could similar exposure to this naturally occurring chemical result in giftedness.
"There seems to be some evidence that excessive prenatal exposure to testosterone facilitates increased connections in the brain, especially in the right prefrontal cortex," said Mrazik. "That's why we see some intellectually gifted people with distinct personality characteristics that you don't see in the normal population."

Mrazik's notion came from observations made during clinical assessments of gifted individuals. He and his fellow researcher observed some specific traits among the subjects. This finding stimulated a conversation on the role of early development in setting the foundation for giftedness.

<rest of article at link>

I wonder if this paper explains why more males than females are more highly gifted in math http://www.dukegiftedletter.com/articles/vol11no1_feature.html , given that testosterone is the principal male sex hormone.

I think the paper being referenced is

http://www.informaworld.com/smpp/content~db=all~content=a927174008~frm=titlelink
The Neurobiological Foundations of Giftedness
Roeper Review
Volume 32, Issue 4, 2010, Pages 224 - 234
Authors: Martin Mrazik; Stefan C. Dombrowski
Abstract
Case studies of extremely gifted individuals often reveal unique patterns of intellectual precocity and associated abnormalities in development and behavior. This article begins with a review of current neurophysiological and neuroanatomical findings related to the gifted population. The bulk of scientific inquiries provide evidence of unique patterns of right prefrontal cortex and inferior frontal activation implicated in gifted intelligence, although additional studies suggest enhanced neural processing and cerebral bilateralism. Geschwind, Behan, and Galaburda (GBG) first hypothesized the possible neurodevelopmental factors that account for unique brain development. This article explores more recent findings taken from the prenatal exposure literature and offers a proposed model for explaining aberrant developmental forces that may be at work in precocious individuals.

Although testosterone is at higher levels in males, it is not a male specific hormone. Males have around ten times as much testosterone as females. The levels vary in both genders with similar effects seen at the relative levels within the gender specific ranges.

John Manning et al, has associated gender specific high levels of testosterone with autism. I have always believed at least some degree of autism is in part responsible for what is classified as gifted. Gifted in my opinion is an indication someone has strengths in the areas our current society sees as valuable. This does not necessarily mean everyone else is any less intelligent, they just have strengths in other areas or less obvious strengths.

I basically agree there may be a coorelation between gifted and prenatal testosterone levels. The coorelation in not linear however as extremely high levels of prenatal testosterone leads to severe disabilities.

Definitely an interesting hypothesis. I agree that there cannot be a linear correlation, as I have seen the negative effects of excess prenatal testosterone in my work with neonates. Gives more weight to their idea of increased testosterone sensitivity vs. excess level of the hormone. As well, they postulate that it is exposure in the second and third trimester that is important. In my DD's case... she missed most of the third trimester and was born preterm. I have often wondered/worried what my complicated pregnancy and horrendous delivery did to her little brain. It would be nice to think that it did something nice to it, as well.

My knowledge in this area has a lot of holes in it, but this is what I understand. The prenatal testosterone levels are generally determined by the genetics of the child and produced by the child's body. However, there are other factors, which can change the sensitivity to these base testosterone levels. In this case, I am not sure if premature birth will necessarily affect the brain development as the child will still produce these levels.

There may be a build in mechanism in woman affecting the sensitivity to prenatal testosterone in males based on male birth order. First born males for instance will develop as if the testosterone was at a lower level than their genetic testosterone level. Later born males will be affected to a greater extent by their genetic testosterone level. This does not appear to affect females and female births do not seem to affect the levels in later born males. In other words, earlier born males will be shifted more towards the more typically female brain side. I do not know if this is the case for the entire human population or just a subset.

Another interesting side note is something I learned from some of my daughter's mom's relatives about their tribal customs. They actually have a tribal role selection process based on male birth order. Found this interesting given what I know from the scientific information I have read about male birth order. Wonder if they noticed the pattern and incorporated it into their customs.

Certain drugs have been known to affect the sensitivity to prenatal hormone levels. A good example of this is in the case of DES babies. As many as one percent of the US/Canada population may have been affected by the use of this drug meant to alleviate morning sickness. It is known as the worst drug disaster in Canadian history. A lot of the plastics used currently have a chemical makeup which is suspected to have the potential to affect human development in similar ways.

I believe post-natal testosterone levels also affect brain development later in life. It may even be the case estrogen levels play a part in this as well. Most of this is just stuff I have come across over the years, with this last part being some thoughts I have on this. I just consider this useful information to be aware of, but I always remain open to the idea of this not being correct or at least not entirely.

You cannot negate the effect of maternal androgens on the fetus, either. Although there are many cases of maternal virilization with no outward negative effect to the fetus, the mother's own testosterone has the potential to alter other aspects of development. Some maternal medications can also alter testosterone levels during pregnancy. The placenta does metabolize a great deal of maternal androgens, but this is a mesh barrier at best. If the hypothesis states that it is PREnatal testosterone exposure that changes neurodevelopment, than one must wonder what effect premature birth would have. If the testosterone was solely fetal in origin, than time of birth would have little impact. If the mother contributed to the increase in hormone, than birth timing needs to be considered.



If the initial hypothesis is shown to be true, than this is a logical follow-up. Brain development does not stop at birth, as we all know, and anything that could affect early development would likely alter it into childhood, if not later.

I find these ideas quite fascinating. It is easier for me to wrap my head around a concrete biological idea as the basis of giftedness, because that is how my brain works best. I so constantly feel out of my element in talking about the subject that it is nice to have someone throw a bone in my direction so I can shake on it for a bit.

The fraternal male birth order effect I mentioned is not conclusively proven, but there is a fair amount of evidence supporting it. Those who have found evidence of it do not have an explanation for it, but suspect it is some form of increased immune response to male fetuses (similar to the increasing rh- immune response in future fetuses). Now if there is no way to affect on androgen sensitivity, I wonder if the effect may somehow reduce prenatal androgen production in some way.

I did a quick search for the effect of early birth and androgen effect, but I didn't on a quick search. Wonder if anyone has done research based on the combination of prenatal androgen and birth timing. I would love to find some information on this myself for interest sake. Hopefully, it turns out to be a more positive effect for your DD.

I am definitely a converted from nurture to nature person. It was more about not being aware of the nature side, which had me being a strong nurture advocate. However, my observations just did not add up by looking only at nurture.

Once I became aware of the nature side, a lot started to make sense. I still struggle with so many of the old ideas I have heard over the years on the nurture side. It is not that I believe nuture is not a factor, it is that nurture has different effects depending on the nature.

I am also happy to see someone looking into the biological side of these issues. It took me a bit to get back to you on this one as I hadn't looked much into this prenatal research for quite a few years. I have been trying to piece a lot of information together from a variety of different sciences related to cognitive research. For this reason, I am not often too deep into one area.

An interesting article relating prenatal exposure of pesticide to lower IQ scores.

http://www.sciencedaily.com/releases/2011/04/110421082519.htm

I've read research that says you only see the genetic effects on IQ in middle classes, that the genetic effects disappear with lower socioeconomic status.

My own interpretation of other research I've read (and lost links for in a catastrophic hard drive crash) is that the biggest genetic/physical factor in IQ may, in fact, be the quality of the myelin insulation on the connections between neurons. I imagine this as being something like the insulation on the ethernet cables that connect computers.

I find something oddly comforting in this notion.

I was surprised to see testosterone mentioned as having a possible relationship with I.Q. I've actually read that high levels of the natural hormone progesterone (not to be confused with synthetic progestin), has been studied as a contributing factor in giftedness. I have no idea if it's true, but what an interesting concept!

As for lowering I.Q., I've read accusations that fluoride can do that. Again, I'm not a physician and have no way of knowing if the studies done are valid.

Here's one article on the effect of progesterone on the fetus.

As a side note, many miscarriages are due to a low level of progesterone early in the pregnancy. Tests will diagnose this. Progesterone suppositories can be given by the OB/Gyn to correct the levels.

Maybe TMI, but I was on progesterone therapy during my pregnancy.