International Left-Handers Day: August 13th.

Today marks an international celebration of left-handedness.

Left-handedness is found in about 7 to 10% of the population. Throughout history, left-handers have been subject to suspicion and marginalization in many cultures, yet recent research has pointed out some interesting gifts that left-handers possess.

To be left-handed is to be different in more fundamental ways than the hand which you choose to write with: it goes deep into the very wiring of the brain. A left-hander's brain is visibly different in form and structure than a right-handers. These differences are critical to understanding the fundamental differences between left and right handers.

Normally the brain, which is divided into two halves in almost all humans (in some cases it is fused, I understand), consists of two different sized halves. For a right hander, one half is larger than the other. For a left-hander, this disparity is not seen: the two halves of the brain are of similar size. There is a good reason for this that we will get onto in a minute.

The left-hander also has a thicker corpus callosum - the bridge that connects the two halves of the brain- than a right-hander. This affords the left-hander greater communication power or "bandwidth" between the left and right halves of the brain. This is key to understanding the advantage that a left-hander holds.

When the brain is confronted with a difficult challenge: either a fast or a hard task, or one that has multiple stimuli at the same time, one half of the brain may easily become overwhelmed. Here is where the left-hander wins. You see when confronted with fast and or multiple stimuli, the left-handed brain will recruit processing power from the other half of the brain. The left hander will share the task across its two fairly equal hemispheres. In this way, the task load on one hemisphere is reduced and the task is more easily overcome. Right handers don't do this well. They rely on the power of their dominant hemisphere to handle the task and are not so good at recruiting assistance from their other brain hemisphere.

Thus, in fast-moving, challenging domains, the left-hander is superior to the right hander. This may be seen in sports, gaming or in any situation that has multiple stimuli. Particular - and critical cases - of this would include fighter pilots - or indeed civilian pilots, in which they are faced with the simultaneous input of a large amount of information in which all must be dealt with at the same time.

In simple terms, the left-hander thinks quicker than the right hander, when the task demands much of them.

It should be noted that this innate advantage for the left-hander will only be noticeable when it is called upon. In slow-moving tasks, without multiple stimuli, the advantage that left-handers possess will not be seen. However, put two people in a situation in which they are pushed to handle a lot of information at the same time - and the left hander of the two, will shine. The right hander will quickly get overloaded by the excessive mental workload.

So, perhaps it is time to acknowledge the gifts of the left-handers among us. Some cultures still find it difficult to accept them as they are, and still encourage them to use their right hand, like "everyone else". This is a mistake. The left-hander is fundamentally not like right handers. They are neurologically and distinct - and have something unique to offer us all.

A left-hander is best for any task that requires a high-throughput of multiple stimuli. So that is where they should be - in fast, hard, demanding roles, with much happening at the same time. That is where they can best make their most natural contribution: the one that plays to their strengths.

This strength of left-handers is commonly known as being good at multi-tasking. So, if it is a multi-tasking role - let the left-handers, handle it.

As careful readers of this blog will already have noted, Ainan, 7, my son, is a left-hander. Most of the rest of the family is mixed handed (ambidextrous) in some way. I will write more of this topic in future.

So, if you have a left-handed child don't adopt the concern of the right handed culture in which we live, that it is somehow unacceptable or problematic: it is not. Left-handedness, as now understood, is a kind of gift in and of itself. It is a misunderstood blessing - so be happy.

This new understanding of left-handedness was written of in an article in the journal Neuropsychology, by the Australian National University researcher Dr Nick Cherbuin. It was published in November 2006.

(If you would like to read of my left-handed son, Ainan Celeste Cawley, a scientific child prodigy, aged seven years and eight months, or his gifted brothers, Fintan, four years and one month, or Tiarnan, eighteen months, please go to: http://scientific-child-prodigy.blogspot.com/2006/10/scientific-child-prodigy-guide.html I also write of gifted education, IQ, intelligence, genetics, child prodigy, child genius, baby genius, adult genius, savant, the creatively gifted, gifted adults and gifted children. Thanks.)

Speed of processing and exams

Exams try to measure the ability of students but, they fail, in many respects. Today I will look at one way in which they fail.

Imagine you have two candidates both of whom have scored equally well in an exam. Are both candidates therefore equal in ability? A traditional view of exams would say so, but there is something which the exam conditions are not able to determine. That is: how fast do the candidates think?

Now, it is obvious that the speed with which someone thinks is very closely related to any true measure of their intelligence. An intelligent person thinks faster than a less intelligent person. In the real world, this will mean that they will solve problems faster than others, which in many roles in life, may have critical implications - as I have addressed before, in another post. So the speed of processing is of real world importance. Yet, it is not really captured by exams.

Exams make an attempt to capture the speed of processing of a candidate by setting a time limit. There is, traditionally, a fixed time allowed to complete the examination. Now, you might think this addresses the issue of speed of processing - but it does not. You see, all it does is set a lower limit of speed that must be met to complete the exam. In other words, it cuts off the lowest portion of ability level, but it does nothing to measure the upper strata of ability. You see a very bright student might finish the exam long before the time limit is up - yet the exam system will neither measure nor reward this speed of processing. The exam conditions will not be able to discriminate between the fast student and the average student.

Is this important? I think it is for, in the real world, the faster thinker, will often be more effective in many roles. Their speed of thinking may prove critical to many of life's endeavours - yet an examination, with a fixed time limit, will never allow you to decide who is the faster of two candidates. Faster implies more intelligent - so exams are not really the best measure of distinguishing between levels of intelligence of candidates.

Obviously, exams distinguish on the basis of the final mark - and that is used as a proxy for intelligence, implicitly, by the academic systems of the world - but it overlooks the vital fact that two candidates who get the same mark, may be very different, in truth. One may think fast, the other may think at an average speed. One may, in fact, be much more intelligent than the other - but the mark will never determine that.

I will give you an example from the real world. Ainan, my son, recently took two exam papers. One of them was one and a quarter hours long. Yet, Ainan completed this in forty-three minutes. After that time, he did not write anything more on the paper, having addressed all the questions. The other paper was one hour long. After thirty-five minutes, Ainan had completed this paper, too.

Now, imagine that another candidate gets the exact same resultant mark as Ainan - but that candidate took exactly one and a quarter hours for the one and a quarter hour paper and one hour for the one hour paper. In the eyes of the academic system, both candidates performed identically - but in actual fact, Ainan was about twice as fast as the other candidate. Implicitly, therefore, Ainan is more intelligent than the other candidate of the same mark, since he is able to solve twice as many problems in the same time, as the other candidate. Yet, no account is made of this in the examining system - and it will be overlooked.

So, don't imagine that all people of the same grade in an exam are the same in ability. They are not - for each would have taken a different time to reach that grade - and would, therefore, have differing levels of inherent processing speed and consequent intelligence.

Exams, with a fixed time limit, establish a lower threshold of performance - and indicate that performance could not have been lower than that threshold - but they do NOT indicate the true heights of which a candidate is capable.

There is one caveat to all of this. In many roles in life, the speed of processing does make a real world difference and is of great importance. I would like to see a policeman who thinks quickly, not slowly - and similarly for an air traffic controller, for instance. Sluggishness, in such roles, could lead to real world danger. There are many such examples that I could provide. However, there are also roles in life in which the speed of processing does not matter. These are roles in which time is not of particular importance and all that matters is that the right answer is eventually reached. The writing of a book might come into this category (though the writing of journalism rewards speed of processing) - or the performance of scientific research (though if you are slow you won't be first and may not succeed in building a reputation and career).

Thus, exams measure performance over a fixed time. They do not measure absolute performance, however, for people will differ in the time taken to achieve a particular level of performance - and therefore differ in true ability. This means that exams, as presently formulated, do not distinguish well between different levels of intelligence: they miss the upper ranges.

This observation is, of course, my thinking alone.

(If you would like to read of Ainan Celeste Cawley, a scientific child prodigy, aged seven years and six months, or his gifted brothers, Fintan, three, and Tiarnan, sixteen months, please go to: http://scientific-child-prodigy.blogspot.com/2006/10/scientific-child-prodigy-guide.html I also write of gifted education, IQ, intelligence, child prodigy, child genius, baby genius, adult genius, savant, the creatively gifted, gifted children, and gifted adults in general. Thanks.)