To wit: While roughly 98% of righties are left-brained as are ~70% of lefties. If each hemisphere of the brain controls the opposite side of the body, how's that possible? Then, too, research indicates there is no significant difference between lefties and righties when it comes to personality traits like extraversion, conscientiousness, and openness to new experiences.
Dr. Sebastian Ocklenburg and his team's new research suggests that the cause of handedness cannot be explained by the brain. Instead, it's the result of the spinal cord's formation. From the 13th week of pregnancy, activity in the baby's spinal cord is already asymmetrical, supporting previous research indicating that in utero babies prefer sucking one or the other thumb.
Apparently, environmental factors that have nothing to do with genes impact symmetry. How? Those factors change the enzyme interactions around the baby, impacting how genes develop, thus affecting whether an in utero baby prefers the right or left hand.
As The Motley Monk is left-handed in somethings (e.g., eating, handwriting) but not in others (e.g., sports, using tools), he's wondering what crazy environmental factors split him in two! The "Handedness Questionnaire" revealed his laterality index is -40.00, which is the 1st left decile (close to being ambidextrous). His augmented (15 item) index is -20.00, making The Motley Monk just about even-handed...a little more to the left than right! (Try taking the questionnaire.)
Let the discussion begin...
To access the website identified in this post, click on the following link: