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In a strange evolution of idiom, the organs of our body are each associated with actions denoting emotions or expressions of different kinds. For instance, when we say “eyeing” something, the undertone of coveting it comes in. “Lip service” is superficial, “Stomache it” implies tolerance. “Have a heart” refers to kindness and compassion and so on.
Convergently, both the hands and legs are used to denote work or help of some kind, as in the phrase “leg-up” and in “helping hand”. But this is not the only phrase involving hands. Traditionally, hands multitask, even in metaphors and phrases: to understand something by grappling with it, you aim at “hands-on” work; when you “throw up your hands” you give up; you absolve yourself of responsibility when you “wash your hands of” something; you “shake hands” to convey warmth, and so on.
Despite this multitude of tasks they are put to, hands are lone rangers most of the time. For the majority of people, it’s one hand that dominates over the other — left or right — depending on and cross-correlated with that half of the brain which is dominant.
The brain has evolved into its two-lobed structure, with each lobe being cross-correlated with the body. That is, the left lobe controls the right side of the body and vice-versa. Also, there is the lateralisation of the brain: the left lobe specialises in some functions like reasoning, linguistic ability, etc., while the right sees the big picture, processes music, art, and is involved in perception.
Loosely speaking, the left side is dominant in nerds while the right is, in artists — that is, if you believe these two classes do not overlap.
However, speaking of overlaps, between 10 per cent and 30 per cent of people, as cited in various sources, are ambidextrous and use both hands equally. This is not a small number, even going by the conservative estimate of just 10 per cent.
In ambidextrous people, both hemispheres of the brain enter into the picture when they act, which is why they don’t show a preference for any side.
Kamindu Mendis, a 17-year-old Sri Lankan cricketer, recently dazzled commentators by switching between the left hand and right when he had to bowl to a rightie or left-handed batsmen. And his batting was not considered bad either. One wonders whether he trained himself to do this or was naturally ambidextrous. Is it even possible to train yourself to work with both hands, and is there some deeper truth to be learnt from that exercise?
There is also the question of whether ambidexterity has negative connotations? For instance, what if the big-picture-thinking and the fine logical side should clash due to functioning simultaneously?
Some studies have shown a correlation between ADHD (Attention deficient hyperactivity disorder) and non-right handedness, especially ambidexterity. These scientists argue that when learning language, for instance, in the majority of people, only the left brain sends out signals. However, in ambidextrous people, the right one too gets involved and this could be potentially distracting.
But this is still seeing one side of the story, only. Chennai-based psychiatrist Suresh Kumar puts forth the following idea — given that the world has grown to favour right-handed individuals, culturally and practically, it is only natural that from their early childhood people who are non-right handed feel pressurised. Being under such pressure, it is not surprising that these people show learning difficulties. A good study, in his opinion, should control for these external and social factors.
Spindle neurons, possessed by humans, primates, dolphins, are the way forward for evolution. And since they connect the two sides of the brains, they must be also pointing towards ambidexterity as the way forward.
Interestingly, there seems to be some natural correlation between ambidexterity and surgeons. Many surgeons have trained themselves to suture up their patients using their non-dominant hand. One famous example is Wilder Penfield (1891-1976), the Montreal-based neurosurgeon who, among other things, is very well-known for having drawn out a functional map of the human cerebral cortex.
As his patients lay conscious under the effects of local anaesthesia, he would operate on their brains and administer a minor shock to some region and ask his patients what they felt. They would respond with “I feel a tingling sensation in my left forefinger,” or something like that, based on which he would deduce which part of the body was controlled by that area of the brain to which he had administered the mild shock. Given the lack of technology, he had to draw out the brain map and he used a sterile pencil and paper for this, on which he is said to have drawn the map using both hands.
Surgeon J.S. Rajkumar reiterates this usefulness of both hands in surgery. In fact, he goes on to advocate training both hands to be equally useful as a means of stimulating the brain to be more active and thereby mitigate the effects of ageing. He also speculates on the connection between spindle neurons and ambidexterity. Spindle neurons are — as the name suggests — very long and spindle-like. And they connect superficial layers of the brain with deeper layers and also the hemispheres of the brain with one another.
These cells are seen only in humans, some primates and some aquatic species such as dolphins. Given this rarity, organisms endowed with spindle neurons are on top of the evolutionary pyramid. And so, it can even be said that the spindle neurons are the way forward for evolution. And since they connect the two sides of the brains, they must be also pointing towards ambidexterity, as the way forward.
