NEW YORK - The length of children's fingers may hint at their natural abilities in math and language, a new study suggests.

A stock broker's fingers key in the day's proceedings on a keyboard in Mumbai, India, May 19, 2004. [Reuters]

In a study of 75 children between the ages of 6 and 7 years old, researchers found that finger length correlated with how well the children performed on standardized tests of math and verbal skills.

Specifically, boys whose index fingers were short compared with their ring fingers tended to excel at numbers and girls with index and ring fingers of similar length tended to do better on the verbal portion of the test.

The findings are reported in the British Journal of Psychology.

A number of studies have now found that "digit ratio," or the length of the index finger compared with the ring finger, is connected to cognitive performance, some personality traits, athletic prowess and the risk of certain medical conditions.

Researchers believe hormones explain the findings. Finger length is thought to be determined in the womb, with exposures to testosterone and estrogen playing a key role. Greater testosterone exposure appears to result in a shorter index finger relative to the ring finger, while estrogen encourages more equality between the two fingers.

Prenatal hormone exposure is also thought to influence brain development.

"Testosterone has been argued to promote development of the areas of the brain which are often associated with spatial and mathematical skills," study leader, Dr. Mark Brosnan, explained in a statement.

Estrogen, in turn, is thought to affect brain areas involved in language ability, noted Brosnan, who heads the psychology department at the University of Bath in the UK.

Therefore, finger length may serve as a marker of fetal hormone exposures, and possibly our inborn math and language abilities.

No one is saying that finger measurements should replace SAT tests, Brosnan added. But finger length does offer "an interesting insight into our innate abilities in key cognitive areas."

SOURCE: British Journal of Psychology, May 2007.