Left-Handedness and Its Causes

Left-handedness is preference for using the left hand rather than the right hand. Left-handed person who uses his/her left hand in writing and doing the most common task tend to favor their left foot and are generally stronger and more skillfull on the left side of the body. There are slightly more left-handed males than females and left-handedness in comparison to the general population also appears more frequently in identical twins. In a study conducted in 1998, it was suggested that about 7 to 10% of the adult population was left-handed. Some individuals are ambidextrous which means they can perform the task equally well using either of their hands. Only few people are exclusively left or right handed.

Left-handed people have a higher incidence of learning and developmental disabilities like autism and dyslexia than the right-handed individuals. On the contrary there is higher number of artists, athletes and scientists who are left-handed. Psychologist advises not to force right-handedness on left-handed children. Such forcing, they believe, may lead to emotional disturbances shown by stammering and in other ways.

Cause of Left-handedness: The real cause of left-handedness is not known although some studies have shown that the possible causes of left-handedness are the following:

• The left half of the brain rules the right side of the body, and the right half the left side. It is believed that the hormone testosterone play a role in determining which hand is dominant by determining which half of the brain is dominant.

• Studies believed that left-handedness is hereditary. Children of the left-handed parents will most likely become left-handed than those Children with right-handed parents. However some people think that the real reason for this is imitation rather than heredity.
• Most children ages 3-6 year old. switch their preference two or three times in the first year. Preference grows with age, and is firmly fixed at five or six years. It is more likely that a large number of naturally left-handed children will adopt to right-handedness, because there are more people for them to imitate. Another thing, most children are taught to use toys, tools, and sport equipment with the right hand. Many naturally left-handed children learn to do everything except to write as right-handers.