Race, Skull Design and Multiple Sclerosis
Race affects the overall design of the skull and cranial vault, and therefore the brain. Although it is a highly contentious issue among physical anthropologists, for practical purposes orthodontists categorize the design of the human skull into three basic races: European, Asian and African.
On a less formal note, when I was a young boy, most of the men in the carpenter's union who built the homes in our neighborhood were of Scandinavian descent from Norway and Sweden. They were tall and had large square looking heads so the other trades colloquially referred to them as the square heads. Technically, square heads are called brachycephalic, which means that the head is as wide as it is long.
The bust in the picture below is a perfect example of a famous person (Beethoven) with a classic square looking skull. Rather than square, some European skull designs are more dolichocephalic. Dolichocephalic skulls are rectangular and have relatively longer bases and narrower widths.
European skulls are also prognathic. Prognathic means protruding jaws. In other words, in European skulls, the muzzle, which contains the nose and jaw, protrudes out from the face.
In contrast to the European race, in the Asian race, the jaws and nose are in line with the face. Interestingly, northern Europeans have a much higher incidence of multiple sclerosis (MS) than Asians. On the other hand Asians get a variant form of MS called Optic Spinal Multiple Sclerosis. In addition, African-Americans also have a low incidence of multiple sclerosis but likewise, get a particularly aggressive form of what some consider to be a variant of multiple sclerosis, called Devic's disease. Optic Spinal Multiple Sclerosis and Devic's Disease are identical. Both are associated with optic neuritis and transverse myelitis which are discussed separately on this website. The difference may be due to the distribution of weight and, therefore, the center of gravity over the cervical spine. The European design is the least balanced.
If you strip away the flesh the square shape of the European race's skull becomes more apparent. The perfect replica cast skull on the right was copied with permission from Bone Clones Inc. The most telltale signs that indicate race are in the shape of the eyes and nose openings. In this skull the eye openings are clearly square. Even more characteristic of its race is the triangular shape of the nose. In contrast, the opening for the eyes and nose are rounder in the Asian and African-American race's skull.
The shape of the skull affects the pitch and layout of its base and the venous drainage system of the brain. The length and width of the base of the skull affects the position of the brain within the cranial vault. Herein lies the crux of the potential impact of race on multiple sclerosis due to skull design.
A short length in the base from the front to the back of the cranial vault, predisposes the brain to crowding and a condition called Chiari malformation in which the cerebellum or brainstem gets pushed down into the foramen magnum. Chiari malformations can block both venous blood and cerebrospinal fluid (CSF) pathways causing CCSVI (chronic cerebrospinal venous insufficiency) and hydrocephalus type conditions.
Chiari malformations used to be considered a childhood problem for the most part and considered to be a herniation of the brainstem into the foramen magnum thus compressing it. More recent research suggests that the definition should be changed to include any decrease in CSF volume which causes the brain to sink and come in contact with the bones of the cranial vault. With this in mind, studies now show that trauma can cause Chiari malformations in adults. What's more, Chiari malformations have also been associated with multiple sclerosis and chronic fatigue syndrome.
The graphic of the ape and human shows the size of the large human skull compared to the relatively small neck. In the ape the head and neck are more in proportion. The body is also supported by four extremities so slips and falls are less likely and the distance to the ground is much closer if a fall does occur.
Humans, on the other hand, are tall and top-heavy and stand upright balanced over a narrow base rooted in the feet. This is actually quite a feat. Upright posture makes it easier to fall, and unfortunately in humans the head has a further distance to the ground and so falls generate more force.
People living in northern climates are exposed to far more winter related whiplash type traumas than people living in southern climates. Motor vehicle accidents and winter sports and activities such as hockey, skiing and snow mobiling significantly increase the risk and the forces involved in trauma.
When it comes to MS and trauma, however, it's not so much the size of the skull that matters as it is how it stacks up on the cervical spine. Moreover, it is also how the brain stacks up over the large hole in the base of the skull, the foramen magnum. Getting back to race and skull designs, brachycephalic Asian and African designs, as well as skulls with short lengths in their base are more balanced on top of the cervical spine. On the other hand, they stack more of the brainstem over the foramen magnum. This predisposes the brainstem and cerebellum to being pushed, pulled or to sink down into the foramen in a Chiari malformation and or pressure conus type condition.
Speaking of round heads, my clinic partner in chiropractic school was part Japanese and part Hawaiian. He had a huge round skull. It was so large I could barely get my thumb and ring finger across his mastoid bones. I used to tease him and say it was perfect for bowling. His eyes, which were mere slits, would get even smaller as he broke out in a grin. I would look him square in the eyes and say how do you see out of those things and the remaining slits would turn into dashes as his grin stretched and strained his cheeks to the max. He was a great human being and loved to joke. His belly splitting Hawaiian laugh was infectious. Many Asians like the martial arts maestro on the right are much more subdued.
The roundness of the Asian race's skull and eye sockets is evident in the cast seen below. The aperture of the nose is also rounder compared to the more triangular shape of the European race skull.
The head is the sound box of the human voice. The tonal quality of the voice is affected by the design of the head, especially the size and shape of the pallate, nose and air sinuses, called the paranasal sinuses.
The bridge of the nose, called the glabella, sits above the opening. Behind the bridge are the ethmoid air sinuses. The large maxillary air sinuses lie beneath the cheek bones to the sides of the nose. The frontal air sinuses are in the forehead just above the nose. The sphenoid air sinus sits behind and between the eyes. Singing resonates in the sinuses and vibrates the air which escapes through the nose. Yoga kundalini exercise uses the AUM chant to resonate (vibrate) the brain, especially the sphenoid sinus, which stimulates the pituitary gland. The difference in shape of the nasal opening affects the escape of air like the difference in shape between "f" holes in violins and jazz guitars and round ones in classic and country guitars.
In this regard, the design of the African-American skull is a perfect shape for singing. One of the finest quality voices ever recorded was that of Nat King Cole. Smooth, rich and mellow, rarely embellished with fancy flourishes, the music would escape his head with near perfect unobstructed flow. A nice wide well rounded arch in the pallate further perfected his distinctive tone.
Again, if you strip away the flesh in these type skulls, it's easy to see that the roundness of an African-American skull is closer in design to Asian skulls. The head is not box-like as in European designs, but smoother and rounder. The eye sockets are also rounder. The nasal aperture is especially round.
The racial skull design difference in the round versus square European head may explain why Asians and African-Americans have a much lower incidence of MS. On the other hand, it may explain why they get optic spinal multiple sclerosis and Devic's disease.
The descriptions above regarding square versus round designs were from an informal frontal or facial perspective. In actuality, it's much more complex. According to recent orthodontic studies, the floor of the rear portion of the base of the skull, called the posterior fossa, is longer in Asian and African skulls. The back wall of the head in Asians is taller but slightly more sloped than African designs which tend to be steeper. The longer base and steep rear wall distribute more of the weight of the brain behind the foramen. On the other hand, it could also favor positioning the brainstem in a more vertical fashion over the foramen magnum predisposing it to sinking into a pressure conus type condition or a Chiari malformation.
With the above racial skull design differences in mind, let's consider a hypothetical example of a European, Asian and African-American traveling together in a car that gets into a serious motor vehicle accident. All of them get whiplash strains and sprains to their cervical spine. They all experience a change of vision and weakness in the legs. Brain scans show small white spots in the brain of the European and long white spots in the cervical cord of the Asian and African-American. In this case the European passenger is diagnosed with MS. The Asian passenger is diagnosed with Optic Spinal Multiple Sclerosis, and the African-American passenger with Devic's disease. In all three cases, it will be blamed on an immunological problem. When in fact, it is simply a different response to the same traumatic cause.
During whiplash the skull and cervical spine are thrust back and forth, along with the brain inside the cranial vault and eye socket. Racial design differences in the skull determine the response to the displacement of the fluids and tissues of the brain and cord inside the cranial vault and eye socket. It may, therefore, explain the difference in incidence of MS in different races. Interestingly, the incidence of MS in Chinese people appears to be rising as more of them drive cars.
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