Brains

The human brain is the product of million of years of evolution, each structure shows a different step in the evolutionary process from what some people call our ‘primitive hind brain’ (which is anything but)  to the cortex structures and language centers which ‘differentiate’ us from our closest  primate cousin.

The human brain is the product of evolution with similar structures present in other species

This is one of the reasons why no matter how well you treat your pet snake he will never see you as anything other than a meal, his brain never developed the ability to be a social animal let alone see you as the love of his life. Similarly you can speak you your dog as much as you like but they will never speak back, language is innate to humans (or apes on Planet of the Apes).

Human brains are laid out pretty much uniformly and understanding of the function of many parts has blossomed in the last 30 years with the advent of computer modelling tools and scanning equipment. A lot of prior knowledge was developed through post mortem examination and accidents, indeed acquired brain injury is still a source of insight into the workings of the brain.

Main regions in the Brain

The Brainstem

The oldest part of the brain from an evolutionary point of view this is where connections between autonomic function (regulation of your heart, blood pressure,  breathing, digestion) and basic responses (sleep, arousal) The Brainstem is the information superhighway with adjustments being made at this level without even conscious decision… nobody every though ‘I must adjust my heart rate to run away from this killer clown’

The Cerebellum

Tagged on at the back of the brainstem like a little extra brain the cerebellum helps co-ordinate the smooth movement of your body, damage to this region can result in cerebellar ataxia where people walk with a drunken gait. Other muscle control such as speech, swallowing and complex coordinated movements are also part of the cerebellums job.

 The Frontal Lobe

This is most highly developed in humans, absent in reptiles it developed as a function of living in social groups. It is in humans involved with a variety of socially mediated behaviours, (like worrying what people think of you -not a problem for snakes.) It also has a number of functions in reward, planning and organisation, emotions and creativity.

Occipital Lobe

Right at the back of the head is the occipital lobe, and its involved in vision. If you’ve been unlucky enough to fall back on your head and saw black it could have been due to a trauma here. While we consider our eyes to be where we see they are merely a set of signalling devices relaying information back to the occipital lobe where that information is translated into an image.But I guess telling the person you love that ‘their visual signalling devices and their occipital nerve are like the sea’ doesn’t have the same ring to it Damage to the occipital lobe can result in permanent blindness despite functioning eyes.

Temporal Lobe

Located either side of your head feel free to threaten people with a clip around the temporal lobes in future. The right lobe in involved with visual memory and the left with verbal memory of words and names.

Related articles

• Brain Shape Confirms Controversial Fossil as Oldest Human Ancestor (richarddawkins.net)