Brainless But Not Stupid!
By Kris Kingsland
Brainless But Not Stupid!
By Kris Kingsland
In this brave, new world, there are times when we might feel that we understand the way in which things work. Of course, even when we know about it, we do not always make use of it. Having conquered the world, it seems there are few uncharted wildernesses left to explore. Even the vastness of space yields its secrets, much like the seemingly 'bottomless' ocean before it. And so now in our quest for adventure, we turn the brilliant searchlight of science inwards, and examine ourselves under its impartial glare.
In about 520 BC Alcmæon of Croton (southern Italy) dissected animals, distinguished veins from arteries, discovered the optic nerve, and recognised the brain as the 'seat of thought'. Not a bad start. Before this (circa 600 BC) Ayurvedic doctors spoke of the sirobrahman, which means the 'seat of consciousness' , in Sanskrit. Although spelt entirely differently, the last syllable is nearly silent and so it is pronounced much like the Latin for brain - cerebrum, which we still use today in modern physiology. To the modern scholar these are extraordinary coincidences!
Then circa 350 BC Aristotle came to the conclusion that the brain was a device for 'cooling the blood'. Presumably he noticed that although the brain only accounted for 2% of our body weight, it got 20% of our blood supply. Suddenly the seat of thought has become a refrigerator! In all fairness, Aristotle was not completely off the mark: the blood cools the brain, not vice versa. This apparently reasonable application of logic, when it failed to take other research into account, is the kind of backward step that can slow progress to a crawl...
Time passed and in 1948, Walter Rudolph Hess perfected a method of electrode implantation into the brains of rats. Lovely. With this latest innovation he could stimulate parts of the brain electrically and observe the behaviour of the rats. This led him to the conclusion that certain instinctive behaviours were associated with particular locations in the brain. Fair enough. But it is still a 'black box' approach. We have input in the form of electrical stimulation, and we have output in the form of behavioural changes. What happens in between is anyone's guess!
The brain is a complex lump of flesh. In recent times it has been likened to computers, with various parts controlling different activities. When you picture a brain, much of what you will imagine is the cerebrum, and its outermost layer is known as the cerebral cortex (the domed bit). Between this cap and the spinal cord are a number of weird structures and fiddley bits. Generally, as long as it works, we could not care less! The trouble is that sometimes it does not...
The other areas are often just as important. This is why we have a thick skull (very thick in some cases... ) to protect it all. Ever bashed a PC with a brick? Me neither (though I admit to being tempted). Nor do I believe that it would respond well. It goes ditto for the brain. Whack it too hard, starve it of oxygen, blood, glucose, or anything else vital and you will soon know about it. For all our robustness, the right noxious stimuli can incapacitate us like grit in the Vaseline. A little brain damage goes a long, long way. Imagine life without some of the traits listed above. Life after an accident resulting in brain damage is probably a lot less fun. Painting an even blacker picture, we are at even greater risk from genetic disorders, pollution, as well as old favourites such as Alzheimer's and CJD. But despair not, for there is hope!
All the doom and gloom does eventually lead to the light at the end of the tunnel, and as in all good stories, this panacea has been largely overlooked. Professor John Lorber has carried out studies alongside his work as a paediatric neurologist, into the strange and often disconcerting condition known as hydrocephalus. This is when there is a build up of fluid in the brain, which causes a bulging of the head and atrophy of the brain. The more fluid builds up, the greater the pressure on the cerebral tissue, and hence the more squished it gets You would think that all individuals suffering from this condition would be in a poor way. You would be wrong...
Many do undoubtedly suffer awfully from this state of affairs, but some remarkable individuals actually have well above average intelligence and to all other intents are quite normal. In fact, one young man has an IQ of 126 and achieved a 1st class honours degree in mathematics, economics and computer studies. Yet he only has a millimetre or two of cerebral tissue lining his cranium! The space that would normally contain the cerebrum is filled with cerebrospinal fluid! Now before you rush off and attempt to duplicate his successes by emptying the kettle into your ear, know this: most hydranencephalics die very young.
Wednesday 18th March was European Brain Day, and lectures about the brain were held all over Europe. I travelled to Southampton, where I was able to asked Professor Ianotti, head of neurology, about some of these more puzzling conundrums. He seemed very straightforward about how little we understand about the brain, and quite open-minded regarding possible explanations. Indeed, his own area of research interest concerns brain damage, and the relatively unknown sequence of events that take place during and afterwards. "It is a black box - around which there are injuries and outcomes." We do not know the relationship between the two. Part of the mystery stems from our lack of knowledge of the brain's capacity to reconstruct itself. Neurones can divide, and have been observed doing so in the brain. Whether humans have this capacity is yet to be established, but if we can grow back a fingertip...
This sort of behaviour is referred to as neural plasticity. Simply put, it is the brain's ability to rewire itself. We see it in action when blind people learn to process touch signals from their fingertips using parts of the brain usually reserved for vision. This sometimes goes wrong as people who have lost limbs in accidents will attest to: phantom pain. When their amputated limb throbs as if it were still there and hurting! It must be bad enough to lose it the first time, let alone be reminded of it with a recurrent ache...
Researchers in the US have established that magnetic fields can influence the way in which the brain forms neural connections. Cohen, Zieman, and Corwell wondered if transcranial magnetic stimulation (TMS, used to induce electric currents on the brains surface) might affect neural plasticity. By the cunning application of a tourniquet, they simulated the amputation of a subject's arm. They then stimulated the regions of the brain associated with movement. Analysis of the results suggests that rapid adaptation can take place and that this short term, neural plasticity can be up or down regulated. This might be used to help patients recover after a stroke, the highest cause of disability and the 3rd biggest killer. It might also be used to cure phantom pain. This means we might be able to move away from drugs that affect the excitability of the brain AND any number of other things in it. TMS is by no means an easy option - I have experienced it, and it hurt! But it is probably the least harmful of the two.
With so many unknown and unaccountable factors involved, it is well nigh impossible to predict future advances in neuroscience. However, one thing is probable: as long as we continue to improve the quality of our minds, doubtless the quality of our lives will follow suit.
© Kris Kingsland 1997