Thursday, August 25, 2005

Sign language: look who's talking

Have you ever listened to a baby trying to make conversation with you? The baby is making a genuine attempt, but just isn't able to speak yet.

Sign language solves that problem. Babies as young as 6 months old can communicate with their hands. The average age when babies start saying meaningful words is around 1 year old. With hand signs they can begin communicating a few months earlier.

Teaching babies to sign can improve their language, vocabulary and reading skills. In addition, eight year olds who had learned sign language as babies scored higher on IQ tests. It can also save a lot of frustrations if babies can sign what they want.

Baby signing is becoming more and more popular, with signing classes for parents and babies popping up everywhere. A signing baby doesn't raise as many eyebrows as it did a few years ago. The movie Meet the Fockers, in which the baby signs with Robert de Niro, helped popularize the phenomenon.

Koko signing "koko"
Maybe signing babies is not such a big surprise if you know of Koko, a gorilla who uses over a thousands words of ASL (American Sign Language). With us humans evolving from apes, some scientists believe that we first communicated through sign and developed speech later. What all this definitely shows is the strong brain-hand connection. It's almost as if we have brains inside our hands.

Even if you never learned sign language, you probably still use hand gestures all the time. There's even a guide to Italian hand gestures (handy for those having trouble pronouncing the words). Vivid gestures help get the message across. But did you know that gestures also help us speak? If you're attempting to speak a foreign language, use your hands more. Your hands might be better at foreign languages than you'd think.

Further reading:

Article on baby signs fom Psychology Today

Research on baby signing

Wednesday, August 24, 2005

Are you masculine or feminine?

Besides genitalia, relative finger length is the only physical trait at birth that's different in males and females. While still in the womb, the growth of our finger digits is affected by the sex hormones testosterone and estrogen. These hormones also have an effect on our brains.

So how to check? Males tend to have a ring finger that is longer than their index finger (average: 1 to 0.96 ratio), while females typically have index and ring fingers of the same length.

John Manning, a biologist who first identified the significance of 'finger digit ratios', says that "females with masculine digit ratios have more masculine behaviors...males with a typically female ratio exhibit more typically feminine behaviors." Boys with female-type finger lengths tend to be more emotional and sensitive. Girls with the male-type finger lengths tend to be more hyperactive and more predisposed to autism. Lesbians are also more likely to have this finger ratio. Some other characteristics possibly associated with these ratios are musical and sports aptitude; on the negative side, risk of early heart disease and breast cancer.

Read the Psychology Today article

A glimpse of Manning's book