When is comes to understanding what the frontal cortex (FrontC) does and how much is it needed then a fascinating starting point is one Phineas Gage of Vermont, USA. The year was 1848 when America was trying to connect it’s east coast cities to it’s west coast ones via the new technology of the steam locomotive and the railroads. Phineas Gage was an experienced railway construction foreman who was responsible for breaking up rock to create a track for the rails. To break up the rock Gage would drill a hole deep into the rock then pour blasting powder (gun powder) into the hole before filling in the hole before an ‘explosion’.

Blasting powder is not like explosives that we use today as it does not detonate. Not to get to complicated but there are two main ways to blow something up: 1) detonation or 2) deflagration. Both work on the idea of creating a wave of energy when one material changes from one state to another giving up energy in the process. Detonoation produces a supersonic (faster than sound – 342 metres per second, 768 miles per hour, 1,236 kilometres per hour or travelling from New York to London in 4.5hours) wave that is very powerful due to the speed of which the wave is going. Deflagration (latin: to burn down) is subsonic so doesn’t carry the same amount of energy because it doesn’t instantly change from one substance to another at certain point but burns (changes with oxygen) producing a hot gas that if contained with eventually create a fault in the surrounding material or will find create the container to more or fire out anything that is holding the pressure in. This is where Gage’s problem started.

Gage had set explosives many times to such an extent that he had his own metal rod. The normal setup would be hole > blasting powder > fuse > sand/clay all tamped down to create a super tight explosive area. When ready someone would notify others there was going to be an explosion light the fuse which would then burn down into the blast powder causing it to burn, expand and exploded into the rock. On this occasion several events were going to happen that would change Gage’s life and our knowledge of brain injury specifically the part above the eyes – the frontal lobe or cortext.

On this day the blasting powder was in the hole along with Gage’s head over it talking to another worker. The metal rod hit the side of the rock hole creating a hot spark setting fire to the blasting powder shooting the rod out of the hole through first the chin then skull of Gage blowing out a large section of his frontal cortex and skull. This is where our understanding of the brain comes in as Gage remained fully conscious throughout the event even walking back to a trailer to be attended to. The reason behind his ability lies is the very unusual form of the injury. The bar went straight up through his chin then his left eye then the left side of his head. The bar didn’t touch any other part of the brain and as I talked about in the triune model of the brain the frontal context is the most advanced and the last developed part ahead of the limbic and administration parts of the brain. To damage just this part of the brain accidentally is quite incredible.

Gage and half a frontal cortex

The extraordinary injury of Gage resulted in reported changes to Gage’s personality. These changes have led to many assumptions to what the frontal cortex does with respect to personality with many reports that Gage changed from a normal individual to one that was impulsive with less self-control. Now that would make sense as the frontal cortex is responsible for high levels of cognition and self-control (that grown up voice on the best thing to do not the easiest or the most pleasurable) so for Gage to change from Captain Reliable to Dr Creepy is not what was reported. In fact the incredible thing about Gage was how little it changed him and let me explain why.

1. Anyone’s behaviour will change after suffering a massive injury. If you are going about your business with a purpose in life and providing for your friends and family and then suddenly you can’t that will affect your personality. Add to the fact that the injury type wouldn’t actually look that bad as Gage wasn’t disfigured but would have struggled to do some task that required cognitive function that would have been something Gage could have done before. The inability to do his normal job resulted in a change in income with Gage joining P. T. Barnum’s American Museum as a living exhibit as the man with half a brain (totally uplifting). Due to the interest and the perseverance of Gage he exhibited himself to make a living. This didn’t last and so Gage became a stage coach driver in Chile that was stable and a job he could do. Sadly he was unable to continue this work due to a direct consequences of the accident – seizures.
   
2. Seizures determined Gage’s ability to live. Before the accident Gage was able to work and live predictability. After the accident he suffered seizures where his body would start to shake and convulse uncontrollably. The reason for this is the connection between the frontal cortex and the motor control of the body through executive function e.g. I’m going to walk over here or pick this up and place it there. Now other parts of the brain are also involved but the frontal context is crucial. Damage to the frontal cortex causes these seizures be it due to a iron pole removing one side of the it through signal problems seen in frontal lobe epilepsy or dementia where all areas of the brain stop performing as well including the frontal cortex. This is one of the hardest parts of dementia. Dementia is often seen as just forgetting things in old age which is common at the start. However as the brain function deteriorates the motor function in what seem like automatic movements is impaired notably swallowing when eating (somatic swallowing). For Gage his ability to operate with seizures would have had profound affects on his personality due to confidence and motor coordination.
   
3. The brain is plastic and adaptable – neuroplastic. The truly remarkable thing about Phileas Gage is not how his personality change (no longer Gage) but how that it didn’t! The accident happened on September 13th 1848 when Gage was 24. Gage died on May 20th 1860 – 12 years later at the age of 36. 36 is clearly not old but Gage survived in many reports a decent man that may have struggled due to his brain damage but was in no way seen as a social outcast that could not be explained through the direct trauma of a severve injury. Some how he survived on one frontal lobe for 12 years. His brain showed neuroplasticity (neural plasticity or brain plastiticity) in taking over the functions of the brain that had been lost replacing the cognitive function that he had lost, not completely but enough to live to a decent standard. Neuroplasticity is the rewiring (not an accurate term but good enough for this level) of a part of brain so that it can take on new function and or capacity. It’s common in developing brains (children) as they are growing and learning new things, promoting good things and inhibiting bad things. To see this in a 26 year old adult is a remarkable feature of brain chemistry and biology.
   However, remember I talked about the nature of the injury in affect it was a frontal lobe labotomy (or leucotomy) where the lobe is cut off from the pre-frontal cortex near our favourite amygdala (AmyG) a surgical operation that is no longer common due to the benefits of the surgery. If the injury to Gage had not gone up but across a hemisphere of the brain he surely would have died due to amount of brain lost and blood vessels affected that power all level of the triune brain model.

After Gage’s death his skull was exhumed and studied by Gage’s doctor and surgeon John Martyn Harlow who Gage knew before the accident and who treated him immediately afterwards. There is differing of opinion as to the true description of Gage’s personality changes due to the relationship between Harlow and Gage’s family and Harlow’s medical opinion on changes in behaviour. However the skull that Harlow did get (along with the bar) show an amazing amount of damage to a human that lived and worked for 12 years (another third of his 36 years) after such an ordeal. Whilst Gage will have been changed by such an incident, and as I’ve said who wouldn’t be, the lesson is how much he didn’t change – he didn’t go on to commit crimes or fall into any level of physical disability except for the seizures. As I continue to explain the brain and it’s behaviour it’s good to remember just how amazing the brain and body can be.