On a large scale, the central nervous system is made up of different brain areas called lobes. For a finer resolution of some of the structures of the brain, we can look to studies carried out by Brodmann. He was able to distinguish variances in cell type and density and mapped out different areas of similar-looking cells called “Brodmann’s Areas.” The functions of many of Brodmann’s Areas aren’t yet well known.
The Lobes of the Brain
There are four brain lobes, each associated with its own function and role. The frontal lobe is associated with higher brain functions as well as self-inhibition. Much like the name implies, it is located behind the forehead at the front of the brain.
The Story of Phineas Gage, a late 19th century railroad worker who was the victim of an accidental explosion resulting in a steel bar blowing entirely through his skull, damaging his frontal cortex, helps elucidate the importance and function of the frontal lobe.. Amazingly, Phineas survived but he was a changed man. Where he was once quiet and polite, he became belligerent and lost many friends due to his lack of self-inhibition. This anecdote is just one example of the importance of the frontal lobe.
The parietal lobe (parietal meaning “wall”) is located on the sides of the head and this lobe is associated with proprioception or the perception of where your limbs are and things like balance. The semicircular canals of the ear provide a sense of balance through the motion of the fluid that flows through those canals. The parietal lobe is where that information is processed.
The temporal lobe is located near the ears and is associated with hearing and auditory perception. The auditory cortex is in the temporal lobe, as is Wernicke’s area, an area of the brain associated with language comprehension. This would indicate that the temporal lobe is not only associated with hearing perception but also with processing auditory information.
The occipital lobe is in the back of the brain and processes visual information. This might seem counterintuitive since the eyes are at the front of the head and the occipital lobe is at the back, but the optic nerves run alongside the bottom of the frontal cortex and cross at the optic chiasm, sending projections all the way to the back of the brain where the visual cortex within the occipital lobe processes visual information.
Further Understanding the Function of the Brain
While scientists still have only a rudimentary understanding of the brain as it functions in its entirety, there are many areas of the brain that are becoming well understood. Visual cortex and retinal pathways have been the target of a great deal of research and grant funding and the progress made in understanding the visual system is just one example of how far technology can take us in understanding brain function.
Mapping the Circuitry of the Brain
As of yet the circuitry of the brain has not been mapped out at a synaptic resolution or even at a resolution of every projection in the brain, however many scientists are currently working on this issue. Once the brain circuitry has been mapped, computer scientists and biologists alike will be able to better understand the function of all the connections in the brain.
 |
