Ever wondered why one is left-handed and the other is not? Or why there seems to be fewer left handers than right handers. Is it just something we learn to have a preference for over time, or is it something to do with our brain orientation from birth?
Research has tried over the years to understand what makes one left-handed and this is on-going todate. It’s long been assumed that gene activity in the brain, depending on which hemisphere shows the most activity, defines whether or not someone is right- or left-handed. However, based on activity in these proto-spinal cords, it seems that there’s some asymmetry going on there that’s never before been detected. This newly discovered activity is taking place long before the part of the brain responsible for movement – the motor cortex – is actually “wired up” to the spine.
Here we look at some known causes of left-handedness:
CAUSE 1: HEREDITARY
CAUSE 2: PREGNANCY
CAUSE 3: CHILDBIRTH
CAUSE 4: MULTIPLE BIRTHS