The neurocranium creates the cranial cavity that surrounds and also protects the brain and brainstem. The neurocranium consists of the occipital bone, two temporal bones, 2 parietal bones, the sphenoid, ethmoid, and also frontal bones—all are joined along with sutures.

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Evolutionary,it is the growth of the neurocranium the has promoted the development of the mind and its connected developments.


Neurocranium: A lateral view showing the skeleton that framework the neurocranium.

Occipital Bone

The occipital bone develops the basic of the skull in ~ the behind of the cranium. That articulates with the an initial vertebra the the spinal cord and likewise contains the foramen magnum, the huge opening the the ability through which the spinal cord passes as it start the vertebral column. The occipital bone boundaries the parietal bones through the greatly serrated lambdoidal suture, and additionally the temporal bones v occipitomastoid suture.

Temporal Bones

The temporal skeletal are positioned at the base and also sides that the skull, lateral come the temporal lobes the the brain. The temporal bones consist of four regions the squamous, mastoid, petrous and also tympanic regions.

The squamous an ar is the largest and most superior region. Worse to the squamous is the mastoid region, and also fused in between the squamous and also mastoid regions is the petrous region. Finally, the tiny and worse tympanic region lies anteriorly to the mastoid.

There space two procedures that originate from the temporal bone:

The zygomatic procedure that tasks from the reduced squamous region and articulates through the zygomatic bone the the cheek. The styloid process projects downwards indigenous the interior of the temporal bone and also provides attachment for number of muscles associated with the tongue.

The temporal skeletal have 4 borders:

The occipitomastoid suture the end the occipital bone and also mastoid section of temporal bone. The squamosal suture separates the parietal bone and also squama portion of temporal bone. The sphenosquamosal suture the end the sphenoid bone and also squama portion of temporal bone. The zygomaticotemporal suture separates the zygomatic bone and zygomatic process of temporal bone.

Parietal Bones

The two huge parietal bones space connected and also make up component of the roof and sides of the person skull. The two bones articulate to kind the sagittal suture. In the front, the parietal bones kind the coronal suture with the frontal bone, and in the rear, the lambdoid suture is created by the occipital bone. Finally, the squamosal suture off the parietal and temporal bones.

Sphenoid Bone

The sphenoid bone is positioned in the middle of the skull towards the front and forms the rear of the orbit. It has actually been described as resembling a butterfly as result of its wing-like processes. The sphenoid bone is divided into several parts: the human body of the bone, two higher wings, two lesser wings, and also the pterygoid processes.

The sphenoid bone is among the most complex in the body because of its interactions with many facial bones, ligaments, and muscles. The body that forms the center of the sphenoid bone articulates v the ethmoid and also occipital bone and forms a key part the the nasal cavity; it additionally contains the sphenoidal sinuses.

The greater wings form the floor that the center cranial fossa that dwellings the frontal lobes and pituitary gland, and also the posterior wall of the orbit. The lesser wings job laterally and form the floor the the anterior cranial fossa and the premium orbital fissure with which several key optical nerves pass.

Ethmoid Bone

The ethmoid bone is a small bone in the skull the separates the sleep cavity native the brain. That is lightweight because of its spongy, air-filled construction and is situated at the roof of the nose and between the two orbits.

The ethmoid bone creates the yellowcomic.comial wall surface of the orbit, the roof of the sleep cavity, and also due come its main location that articulates with numerous bones that the viscerocranium. Within the neurocranium that articulates with the frontal and sphenoid bones.

Frontal Bone

The frontal bone forms the front of the skull and is divided into three parts:

Squamous: This part is large and flat and forms the main an ar of the forehead. Orbital: This part lies inferiorly and forms the superior border of the orbit. Nasal: this part is smaller and articulates through the nasal bones and maxilla to contribute to the roof of the nose.

The frontal bone borders two various other neurocranial bones—the parietal bones v the coronal sutures and the sphenoid bone through the sphenofrontal suture. It additionally articulates v the zygomatic and also nasal bones and the maxilla.

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Key Points

The eight bones of the neurocranium type major sections of the skull and also protect the brain. The neurocranium consists of two temporal bones situated to the base and also side the the skull, and also two parietal skeletal that consist of the roof the the skull. A solitary occipital bone develops the base of the skull, and the frontal bone creates the forehead. The sphenoid and also ethmoid bones situated to the former of the skull type parts the the orbit sockets and nasal cavity; they likewise support and also protect vital organs discovered in the skull.