I like to keep up to date on new developments in Psychology. It’s a subject that has always interested me.
All spiritual beliefs aside, I try to keep an open mind regarding how scientists try to explain our existence and how we came to be. I came across this article from Psychology Today and after reading it, decided to share it with you.
After taking note of the fact that my right hand index finger is 1/4″ shorter than my ring finger I regret to inform you that I am a hyperactive autistic Lesbian.
Believe me, my husband was quite shocked!
(Please note that I edited this article, ommitting some of the less interesting details. If you’d like to read the entire article please visit the URL at the end of this post.)
Sexuality: Your Telltale Fingertips
How your hands are a marker for behavior. Relative finger length—or digit ratio—is a marker for brain differences molded by hormones.
By: Willow Lawson
Look down at your right hand. Is your ring finger longer than your index finger? Or vice versa? To be certain, take a ruler and measure from the bottom crease of each finger to the tip.
The measurements tell you something about the environment of your mother’s womb just weeks after your conception, a time when your fingers, and more importantly, your brain, were developing. Because of the influx of sex hormones at this prenatal stage, men tend to have ring fingers that are slightly longer than their index fingers. In women, these fingers are usually the same length or the index digit is just a bit longer.
Digits are subtly affected by testosterone and estrogen produced in the womb by the fetus (not by the mother). Between weeks 8 and 14, tiny fetal testes, ovaries and adrenal glands secrete the baby’s own supply of sex hormones. These chemical messengers, particularly testosterone, cause chain reactions in the body, spurring the growth of the genitals, encouraging and inhibiting growth in brain regions and causing changes in the fingers. Many scientists believe relative finger length—or digit ratio—is a marker for brain differences molded by hormones. Like a bit of prenatal graffiti, a longer ring finger says, “Testosterone was here.”
John Manning, a biologist at the University of Liverpool, first identified digit length as a sign of prenatal hormones eight years ago. He believes digit ratio is an important, if indirect, tool for studying the fetal brain and the womb, an environment that’s off-limits to scientists except for analysis by amniocentesis…
“Early sex hormones have an organizing effect on the brain that’s permanent,” Manning says. But the differences between the sexes aren’t all that interesting to biologists. More telling are the variations within each sex. Females with masculine digit ratios have more masculine behaviors, he says. Likewise, males with a typically female ratio exhibit more typically feminine behaviors.
A study of digit ratio in Scottish preschool children between the ages of 2 and 4 found strong relationships between digit ratio and gender-normative behavior. Girls with masculine-type finger ratios tend to have higher hyperactivity scores and more problems relating to their peers than do other girls. The same study, published in Early Human Development, found that boys with female-type finger lengths are on average more emotional than other boys. “They tended to be very sensitive,” says Manning…
“Everything you see as far as sex differences in the behavior of toddlers is an aftereffect of prenatal testosterone,” says Dennis McFadden, a psychology professor at the University of Texas at Austin. Manning and others have linked finger length ratios to aggression, left-handedness, heart disease, autism and attention deficit disorder, all traits that are more common in men. (Studies indicate they are most common in men with longer than average ring fingers.) A “masculine” finger pattern seems to similarly mark girls predisposed to hyperactivity and autism.
Some scientists believe prenatal sex hormones are also part of the puzzle of homosexuality and that a high level of testosterone may wire the brain for attraction to the same sex. Intriguingly, research shows that a prenatal testosterone level is most strongly linked to homosexuality in women, according to an article in the Archives of Sexual Behavior. Lesbians are more likely than straight women to have a masculine finger ratio, says McFadden…
Even as digit ratio research flourishes and more behavioral links are established, the relationships will remain mere statistical correlations until researchers fully understand how sex hormones physically affect the brain. The reigning hypothesis is that testosterone encourages growth in the right side of the brain, while inhibiting growth in the left. Animal models using rats, mice and sheep show that testosterone boosts growth in a part of the hypothalamus involved in sexual behavior and fertility. In sheep, males with hypermasculinized brains are sexually attracted to other males…
Psychology Today Magazine, Jul/Aug 2005
Last Reviewed 31 Mar 2008
Article ID: 3791
http://www.psychologytoday.com/rss/pto-20050614-000004.html
Tiffany on April 6th, 2008 | File Under Life, Uncategorized | No Comments -
So most of my Saturday was spent in the waiting room of the ICU with my in-laws. I don’t really have much of an update on my father-n-law’s condition, except to say that he is resting and that we plan to go and see him again tomorrow. 
