February 11, 2013
The violin is known as the instrument most commonly offered to children by state schools in the UK. It’s a challenging instrument, because rapid independent motion of the digital joints in the left hand is desirable… and a requirement in order to become a top violin player! A brand new study focussed on the pinky finger was designed after an 11-year-old patient volunteered that she had given up playing the violin because of difficulty and discomfort manoeuvring the left small and ring fingers independently. On examination, she was found to have absent FDS (flexor digitorum superficialis) function in the small finger – a condition that can be found in about 6% of the general populaton.
Do you have the ‘flexor digitorum superficialis’?
You can test this right now at home (see also the video below): hold down the index, middle, and ring fingers of your left hand, then try to bend your little finger. Now try it again, but allow your ring finger to bend as well.
Can you do it?
The UK study revealed that about 18 percent of people can do neither!
However, in a group of 90 professional musicians from “three of London’s leading orchestras” (38 first violinists, 33 second violinists, 19 viola players), none lacked this ability, and all but two were able to bend just their pinky finger!!!
Via: The Atlantic
November 20, 2012
Polydactly (extra fingers) is one of the 10 most common pediatric orthopedic conditions, and this condition has been studied as early as the days of Charles Darwin, who suggested that the condition of having more than the usual number of fingers or toes (polydactyly) was an ancient trait, now mostly formant, that occasionally reappears due to some hereditary misstep.
Basically, there are three polydactyly variants:
A – most common is the variant featured with an extra pinky (see picture above)
B – less common is the variant featured with an extra thumb
C – rare is the variant featured with an extra index finger, middle finger or ring finger
A few (recent) reports about polydactyly:
Last summer professor John T. Manning re-designed his popular 2D:4D digit ratio theory about finger length ratio development in the hand. While he had already mentioned the role of prenatal sex steroids, now the updated theory now focusses on the balance between sexe hormones (androgens) testosterone & oestrogen during the development in the whomb!
Professor Manning presented his revised theory in the PNAS magazine under the title: ‘Resolving the role of prenatal sex steroids in the development of digit ratio‘.
Manning’s new working hypothesis now includes e.g. the following 7 key-elements:
1 – The 2D:4D digit ratio results from the balance between prental androgens testosterone & estrogen;
2 – A high 2D:4D digit ratio results from relatively low testosterone concentrations – OR relatively high estrogen concentrations;
3 – A low 2D:4D digit ratio results from relatively high testosterone concentrations – OR relatively low estrogen concentrations;
4 – The ring finger (= digit 4D) is featured with many more hormone receptors compared to the index finger (- digit 2D), therefore the 2D:4D digit ratio is mostly driven by changes in the length of the ring finger (due to prenatal hormone concentrations);
5 – Studies in human & animals indicate that the link between prenatal androgens and 2D:4D digit ratio is generally stronger for the right hand;
6 – 2D:4D Digit ratio varies with sexe: males generally have longer fourth digits relative to second digits than females;
7 – 2D:4D Digit ratio varies with ethnicity.
A quote from Manning’s article:
“Armed with this list of skeletogenic genes linked to 2D:4D, we can now be more focused in our examination of the links between 2D:4D and the etiology of sexdependent behaviors and diseases of the immune system, cardiovascular disorders, and a number of cancers.”
“Prenatal sex steroids [i.e., prenatal testosterone (PT), prenatal estrogen (PE)] are often implicated in the etiology of behaviors and diseases. They show sex differences (higher concentrations of PT to PE in males), with PT peaking at the end of the ﬁrst trimester, and cause permanent “organizational” changes in the brain and other organ systems. It has een suggested that relative levels of PT and PE may have differential effects on fertility, speed, strength, aggression, autism, many cancers, and heart disease.”
September 6, 2011
Wearing your heart on your sleeve is merely an adage, but most people do display their emotions – even if unintentionally – on their faces. Women tend to be better than men at reading other people’s subtle facial cues, especially cues from the eyes. Because of the gender difference in cognitive empathy – the ability to notice and correctly interpret body language – psychobiologistsscientists that study psychology from a biological perspective, or vice versa have hypothesized that testosterone – a sex hormone present in much higher levels in males versus females levels – could play a role in “mind reading” ability, or lack thereof.
A new study in PNASProceedings of the National Academy of Sciences validates this hypothesis by demonstrating that a dose of testosterone can make women lose some of their cognitive empathy. Researchers recruited 16 young women (age 20-25) to participate in their study. The women were given either a testosterone pill or a placebo, and then tested on their ability to assess emotions based on photographs of eyes. The test the women took is called the Adult Eyes Test, and is available for free from the Autism Research Center at the University of Cambridge. Here’s a sample question (formatting is slightly modified):
For the correct answer, click here.
Each woman was tested twice – once with placebo and once with real testosterone (in random order; they didn’t have any idea which was which). 75% of the women performed worse on the “mind reading” test after taking testosterone than after taking a placebo. So to a first approximation, an artificial increase in testosterone levels impaired women’s abilities to interpret facial expressions.
But the results aren’t quite that simple. Some women were less affected by the extra testosterone than others, and the researchers had a hunch that this could relate to their exposure to testosterone in the womb. All fetuses are exposed to testosterone while developing, but to different extents. There is a simple way to qualitatively measure fetal testosterone exposure – this parameter is believed to be correlated to the adult ratio of ring finger length to index finger length (see picture at the top of this post).
Larger ratios of ring finger to index finger lengths correspond to higher fetal testosterone levels. This study showed no difference between the inherent expression-reading ability of women exposed to higher vs. lower doses of testosterone in the womb. However, the women with longer ring fingers (higher fetal testosterone) seemed to be more easily impaired when given a dose of testosterone in pill form.
Thus, this study demonstrated that (1) testosterone administered to women can impair their ability to read facial expressions, and (2) women who experienced more testosterone in the womb are more sensitive to the effects of testosterone administered as adults. Nothing further can be definitively gathered from these results, but they seem to suggest that men’s testosterone levels could be to blame for their increased confusion about what others (especially women!) are thinking/feeling.
PS. A brand new study reported by researchers from Florida has recently (sep 2011) presented proof that fingers have hormonal receptors!
The following finger length study presents a likewise effect:
How lingerie can sharpen the financial mind!
JULY 4, 2011 – Finally… researchers in Korea think that they found the long awaited proof: finger length can predict penis length! Korean researchers at the In Ho Choi of Gacheon University Gil Hospital, have presented results in a sample of urological patients which indicate that in men with a low ‘2D:4D finger ratio‘ more often is featured with a long phallus (compared to men with a high ‘digit ratio’).
The researchers from Korea found that the ratio between the pointer finger & ring figner (2nd and 4th digits) on men’s right hand correlate to the length of his flaccid and stretched phallus (not errected). A lower index-to-ring finger length ratio indicates a longer (stretched) penis.
NOTICE: The table below is taken from the scientific article; it e.g. illustrates that likewise results were found for body length and penis length – for the ‘flaccid condition’ the result for body height were slightly higher than for the 2D:4D digit ratio, but in the ‘stretched condition’ finger length ratio was a better predictor for penis length!
The key to this relationship between penis size & finger length likely lies in the womb, a team member added:
“During the fetal period, high concentrations of testosterone lead to high testicular activity, resulting in a lower digit ratio, in the present study, patients with a lower digit ratio tended to have a longer stretched penile length.”
The researchers also added that the length of the stretched and flaccid penis does show “a strong correlation” with an erect penile length.
The Korean report was published on july 4 in the Asian Journal of Andrology, and the scientific article is available at Nature.com.
NO SURPRIZING RESULTS!
Actually, the Korean results are not surprizing at all. Because British professor John Manning had already pointed out in his second book ‘The Finger Book‘ (2008) that a study in the Naval and Veteran’s Hospital of Athens (Greece, 2002) had pointed out that the length of the index finger correlates with the length, glans & volume of the penis.
Manning commented (in ‘The Finger Book’):
“Spyropoulos and his collegues did not measure the remaining fingers, so we cannot be sure of their relationship to penis length. My guess is that they would have found the ring finger the strongest predictor, and that long ring fingers in relation to index fingers would be associated with longer penises.”
So, the 2011 Korean study shows ‘finger professor’ John Manning was right… again!
MORE ABOUT THE SCIENCE OF FINGERS:
48 Reports about the 2D:4D finger length ratio!
December 29, 2010
Earlier this month, British researchers published new research presenting a link between the relative length of the index finger and the risk of developing prostate cancer. In men with an index finger longer than the ring finger the chances are 33% higher for not developing the disease.
Often such studies are qualified by non-experts as “nonsense” – initially because of the association with classical palmistry. Usually a main argument of concern is the seize of the studied sample: many ‘2D:4D digit ratio’ studies have been focused relatively small samples, and usually with the statistics were simly not strong enough to be applied to individuals. But those arguments can not be used to the describe the new British study!
The new British research involves a study where the hands of 1,524 prostate cancer patients were examined, which were compared with a control group of 3,044 men.
It can also be noted that Professor John Manning described in his second book ‘The Finger Book‘ with great details the suspected link between the ‘2D:4D digit ratio’ and prostate cancer – a complex theory about of role glutamine chains in the sensitivity of hormone receptors, which in their turn play a role in the activation of testosterone in the body:
“…The various forms of the androgen receptor have important consequences for our health and behaviour. For example, African-American men have shorter glutamine chains (high sensitivity to testosterone) than white men. Short glutamine chains are associated with an increased susceptibility to prostate cancer, and this may in part explain why the incidence of prostate cancer is higher in African-Americans than in white Americans. …”
In short, there seems to exist a triangular relationship between: 1) the high percentage of prostate cancer in Americans with African ancestry, 2) the length of the glutamine chains, and 3) the length ratio between index finger and ring finger.
The importance of the new British study can be recognized in the fact the use of preventive screening for prostate cancer – which is anno 2010 usually done through the use of a blood test – is still an object of confusion. Simply because the benefits of the screening devices are still very unclear. Meanwhile it is a fact that prostate cancer is known as the No. 1 cause of death from cancer in men (see picture below).
The British researchers therefore are speculating about how to add a practical application of their finger length study to the traditional methods of prostate cancer prevention screening!
Researchers presented earlier today new evidence that neanderthals were more competitive & promiscuous than we are today! Maybe more surprizing is the method which the researchers used to acquire their new findings: via finger length measurements!
The study, published in the Proceedings of the Royal Society B, draws upon a famous and controversial indicator of social behavior: the comparative length of the index finger and the ring finger, also known as the 2D:4D finger ratio. If the ring finger is longer than the index finger, that’s supposed to be correlated with higher prenatal exposure to androgens — resulting in a higher proclivity for aggressiveness and promiscuity.
Scientists, in collaboration with researchers at the universities of Southampton and Calgary, used finger ratios from fossilised skeletal remains of early apes and extinct hominins, as indicators of the levels of exposure species had to prenatal androgens – a group of hormones that is important in the development of masculine characteristics such as aggression and promiscuity.
It is thought that androgens, such as testosterone, affect finger length during development in the womb. High levels of the hormones increase the length of the fourth finger in comparison to the second finger, resulting in a low index to ring finger ratio (2D:4D digit ratio). Researchers analysed the fossil finger bone ratios of Neanderthals and early apes, as well as hominins, Ardipithecus ramidus and Australopithecus afarensis, to further understanding of their social behaviour.
The team found that the fossil finger ratios of Neanderthals, and early members of the human species, were lower than most living humans, which suggests that they had been exposed to high levels of prenatal androgens. This indicates that early humans were likely to be more competitive and promiscuous than people today.
The results also suggest that early hominin, Australopithecus – dating from approximately three to four million years ago – was likely to be monogamous, whereas the earlier Ardipithecus appears to have been highly promiscuous and more similar to living great apes. The research suggests that more fossils are needed to fully understand the social behaviour of these two groups.
Dr Susanne Shultz, from the Institute of Cognitive and Evolutionary Anthropology at the University of Oxford describes:
“Social behaviours are notoriously difficult to identify in the fossil record. Developing novel approaches, such as finger ratios, can help inform the current debate surrounding the social systems of the earliest human ancestors.”
And Dr Emma Nelson, an archaeologist from the University of Liverpool, argues that comparing the finger-length ratios of extinct and present-day species is a valid technique for making an indirect assessment of our long-gone ancestors’ social behavior. She said:
“It is believed that prenatal androgens (male sex hormones) affect the genes responsible for the development of the fingers, toes and the reproductive system. We have recently shown that promiscuous primate species have low index to ring finger ratios, while monogamous species have high ratios.”
“We used this information to estimate the social behaviour of extinct apes and hominins. Although the fossil record is limited for this period, and more fossils are needed to confirm our findings, this method could prove to be an exciting new way of understanding how our social behaviour has evolved.
Will Your Man Cheat …?
[tweetmeme source=”handresearch” only_single=false] What if you could find out if your man is at a higher risk for infidelity before you married him? Dr. Phil and his panel of medical experts discuss the new science behind a cheater’s brain and what can be done if your loved one is at a higher risk. Author of Change Your Brain, Change Your Body, Dr. Daniel Amen, author of Insatiable Wives, clinical psychologist Dr. David Ley, Claremont University’s Dr. Paul Zak and author of The Male Brain, neuro-psychiatrist Dr. Louann Brizendine explain how you can discern a man’s risk for infidelity and the treatment options to lower his risk.
Dr.Phil.com presents a 4 item list of physiological indicators that your han is at a higher risk for cheating:
Length of ring finger compared to pointer finger: The length of a man’s ring finger is linked to testosterone in utero and during puberty. A longer ring finger means more testosterone, and the increased likelihood of a greater number of sex partners and a higher risk of cheating.
- Facial symmetry and size of jaw: If one side of a man’s face matches the other side, is symmetrical, the more it is an indicator to women that that man has high genetic value. Men whose faces are more [symmetrical] are more likely to have more partners because more women want to have their children.
- Size of penis: If a male is well-endowed, that means more testosterone and a higher risk of cheating.
- Brain injuries: Men with a history of engaging in impact sports like football or martial arts, or men who’ve had a history of concussions are at a higher risk. Also, men with disorders like ADD or bipolar disorder have low pre-frontal cortex activity or hyper-frontal activity, which could mean less ability to stop impulsive behaviors, like cheating.
By the way, did you know that… Casanova had the long ring finger!
SUGGESTION FOR FURTHER READING:
• BBC Test: finger length & sex I.D.!
• Finger length & Cupid’s science!
• The science of gaydar: finger length & sexual preference!
• What they say about men with long ring fingers!
June 26, 2010
[tweetmeme source=”handresearch” only_single=false] Football has a pedigree dating back to mediaeval England, when villagers hoofed an inflated pig’s bladder around a muddy paddock. Today, though, the 22 football players on the pitch are supported by a ghost squad of scientists drawing on biomechanics, physics, nutrition, psychology and other performance-enhancing disciplines.
The Bangkok Post presents 10 illustrative examples of how science has helped to change football, answer riddles and end hearsay!
THE BANGKOK POST REPORTS:
“DIGITAL FUTURE? – Punters looking for a tip on this year’s World Cup winners might be advised to take a close look at players’ hands. John Manning from Britain’s University of Liverpool suggests there is a link between the lengths of a footballer’s fingers and his ability as a player. Looking at British players, Manning found that the footballing elite had longer ring fingers compared to their index fingers. Manning’s theory is early exposure to testosterone in the womb is a key to heart formation and spatial judgement and finger length, which is why digits can be a telltale, but not a prediction, of prowess.”
SUGGESTIONS FOR FURTHER READING:
[tweetmeme source=”handresearch” only_single=false] Over the years various artists have written a song titled with just one word …’Hands’ – Which song is your favourite?
An overview of some of the songs:
• ‘Hands’ – lyrics by: The Almost.
• ‘Hands’ – lyrics by: L.A..
• ‘Hands’ – lyrics by: The Raconteurs.
• ‘Hands’ – lyrics by: Jewel.
• ‘Hands’ – lyrics by: The Dutchess & the Duke.