Friday, 1 August 2014

How to achieve your potential, and use less of your brain


I have never achieved my potential. Potential is indeterminate, though not infinite; achievements are limited by ability, inclination and lifespan.

Personally, although I am sad when thinking about all the things I could have achieved, my greatest sadness is for that smallest subset: those things which were in the believable category. I have given up, only slightly reluctantly, the thought that I might have solved the problems of the Middle East, but remain troubled that my few publications were restricted to reporting findings, not proposing useful theories. So, like all regretful ruminations, my focus is selective: I concentrate on the perceived difference between my immense talents and my humdrum achievements, but I do not dwell on the possibility that I was promoted above my true ability level, and that I should count myself lucky to have used my meagre talents to disproportionately good effect.

The seduction of the word “potential” is that it is immensely flattering: it is the “panoply of talents” trope with which teachers seek to encourage their run of the mill students, a category which encompasses most of us. No-one can deny potential, or so the contemporary mores demand, but it leads people to forget that errors of prediction go both ways.

In education we have to deal with over and under achievement. Typically we give students a test of ability and another test of scholastic achievement. Relative to the predictions derived from the ability test, some students under-perform and some over-perform. Putting it in dramatic terms, some students fail to achieve their potential (but some exceed it). Educationalists rush to give special lessons to the under-achievers and (less frequently) to interview the over-achievers so as to pick up useful tips about how they did so well. Of course, even a good test of ability will not correlate perfectly with Reading or Maths so in the multiple regression equation there will be errors of prediction. By improving on the ability measures (giving two or three different ability measures  over several months and extracting a g factor) and by improving on the scholastic measures (by giving two or three different scholastic exams and extracting a S for scholarship factor) we can bump up the correlation, but there will still be errors of prediction, or residuals, as they are known. They are errors: the under achievers have not been cheated by their educators (though some attempt to sue the school systems) and the apparent over achievers have not got secrets to impart. So, no-one will exceed their potential, though some will apparently exceed their ability and some will under-perform against that standard.

Now a short word about what percentage of your brain you are using, and whether you would do better in life if you found a way of using a higher percentage of your brain. Currently, we do not have agreed measures of how much of our brains we are using. We can estimate blood flows and, subject to a whole number of assumptions, estimate the levels and areas of the brain which are active as far as our much improved, but hardly perfect, imaging systems can report to us. Question is: would using more of our brain improve our performance?

By way of analogy, consider the relationship between horsepower and the speed of a car. Cars with large engines and more horsepower accelerate faster, but relatively little horsepower (about 25 hp) is used at speed in normal cruising. With a good gearbox relatively little horsepower is required even at somewhat higher speeds, where the main load is pushing air out of the way of the car body. Although learning a new task requires concentration, repetition and practice, bright people use little of their brain power once they have mastered a task. Brighter brains can concentrate, learn and then idle at speed.

Many people have a residual and touching faith in psychological witchcraft, and would like to press a secret button (the navel, perhaps) to give a boost to their central processor when a difficult problem heaves into view. If the history of scientific discovery teaches anything, it is that valuable insights depend on learning the fundamental steps in scientific knowledge and then worrying away at big problems from many angles, all of which is time consuming. Then, once the best solution is shown to fit, the problem becomes much simpler.

So, educate yourself, but do not imagine that education of itself will lead to great new discoveries. Education is a gearbox, but it relies on the engine, and cognitive engines vary 7 fold. Do not spend even one second on trying to “use more of your brain”. You will waste more of your time, and given you fell for that nonsense, you have little time to waste.

This note was written on a laptop running at 4% of CPU capacity. At one stage it reached a maximum of 55% capacity. How very stupid of it.


  1. The over-sized human brain is so metabolically expensive, physically burdensome and hazardous to birth that it seems strange that it would have evolved to get so big in the first place. unless we generally needed our entire brain volume, though perhaps we don't need all of it at once. And yet I can't discuss the topic of brain size in everyday life without someone insisting that brain size is irrelevant because we only use 10% of our brains. Wikipedia has an article disagreeing with this conventional wisdom:

    It is interesting that people with certain types of brain damage are not impaired on IQ tests, but of course the brain serves other functions beyond cognition and even the best IQ tests can not possibly come close to sampling all cognitive abilities.

  2. Thanks. Human brains could not have evolved to their current size unless they conferred an advantage. Some effects of brain damage do not show up on over-learned crystallized subtests, but they can be revealed by learning trials. I spent much of my PhD discussing these differences.