|
Meninx
In anatomy, the meninges (, ''singular:'' meninx ( or ), ) are the three membranes that envelop the brain and spinal cord. In mammals, the meninges are the dura mater, the arachnoid mater, and the pia mater. Cerebrospinal fluid is located in the subarachnoid space between the arachnoid mater and the pia mater. The primary function of the meninges is to protect the central nervous system. Structure Dura mater The dura mater ( la, tough mother) (also rarely called ''meninx fibrosa'' or ''pachymeninx'') is a thick, durable membrane, closest to the skull and vertebrae. The dura mater, the outermost part, is a loosely arranged, fibroelastic layer of cells, characterized by multiple interdigitating cell processes, no extracellular collagen, and significant extracellular spaces. The middle region is a mostly fibrous portion. It consists of two layers: the endosteal layer, which lies closest to the skull, and the inner meningeal layer, which lies closer to the brain. It contains l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arachnoid Mater
The arachnoid mater (or simply arachnoid) is one of the three meninges, the protective membranes that cover the brain and spinal cord. It is so named because of its resemblance to a spider web. The arachnoid mater is a derivative of the neural crest mesoectoderm in the embryo. Structure It is interposed between the two other meninges, the more superficial and much thicker dura mater and the deeper pia mater, from which it is separated by the subarachnoid space. The delicate arachnoid layer is not attached to the inside of the dura but against it and surrounds the brain and spinal cord. It does not line the brain down into its sulci (folds), as does the pia mater, with the exception of the longitudinal fissure, which divides the left and right cerebral hemispheres. Cerebrospinal fluid (CSF) flows under the arachnoid in the subarachnoid space, within a meshwork of trabeculae which span between the arachnoid and the pia. The arachnoid mater makes arachnoid villi, small protrusion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dura Mater
In neuroanatomy, dura mater is a thick membrane made of dense irregular connective tissue that surrounds the brain and spinal cord. It is the outermost of the three layers of membrane called the meninges that protect the central nervous system. The other two meningeal layers are the arachnoid mater and the pia mater. It envelops the arachnoid mater, which is responsible for keeping in the cerebrospinal fluid. It is derived primarily from the neural crest cell population, with postnatal contributions of the paraxial mesoderm. Structure The dura mater has several functions and layers. The dura mater is a membrane that envelops the arachnoid mater. It surrounds and supports the dural sinuses (also called dural venous sinuses, cerebral sinuses, or cranial sinuses) and carries blood from the brain toward the heart. Cranial dura mater has two layers called '' lamellae'', a superficial layer (also called the periosteal layer), which serves as the skull's inner periosteum, ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Meningeal Artery
The middle meningeal artery ('' la, arteria meningea media'') is typically the third branch of the first portion of the maxillary artery. After branching off the maxillary artery in the infratemporal fossa, it runs through the foramen spinosum to supply the dura mater (the outer meningeal layer) and the calvaria. The middle meningeal artery is the largest of the three (paired) arteries that supply the meninges, the others being the anterior meningeal artery and the posterior meningeal artery. The anterior branch of the middle meningeal artery runs beneath the pterion. It is vulnerable to injury at this point, where the skull is thin. Rupture of the artery may give rise to an epidural hematoma. In the dry cranium, the middle meningeal, which runs within the dura mater surrounding the brain, makes a deep groove in the calvarium. The middle meningeal artery is intimately associated with the auriculotemporal nerve, which wraps around the artery making the two easily identifiabl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Skull
The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, these two parts are the neurocranium and the viscerocranium ( facial skeleton) that includes the mandible as its largest bone. The skull forms the anterior-most portion of the skeleton and is a product of cephalisation—housing the brain, and several sensory structures such as the eyes, ears, nose, and mouth. In humans these sensory structures are part of the facial skeleton. Functions of the skull include protection of the brain, fixing the distance between the eyes to allow stereoscopic vision, and fixing the position of the ears to enable sound localisation of the direction and distance of sounds. In some animals, such as horned ungulates (mammals with hooves), the skull also has a defensive function by providing the mount (on the f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Falx Cerebelli
The falx cerebelli is a small sickle-shaped fold of dura mater projecting forwards into the posterior cerebellar notch as well as projecting into the vallecula of the cerebellum between the two cerebellar hemispheres. The name comes from two Latin words: ''falx'', meaning "curved blade or scythe", and ''cerebellum'', meaning "little brain". Anatomy The falx cerebelli is a small midline fold of dura mater projecting anterior-ward from the skull and into the space between the cerebellar hemispheres. It generally measures between 2.8 and 4.5 cm in length, and approximately 1–2 mm in thickness. Attachments Superiorly, it (with its upwardly directed base) attaches at the midline to the posterior portion of the inferior surface of the tentorium cerebelli. Posteriorly, it attaches to the internal occipital crest; the inferior-most extremity of its posterior attachment frequently divides into two small folds that terminate at either side of the foramen magnum. An ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebellum
The cerebellum (Latin for "little brain") is a major feature of the hindbrain of all vertebrates. Although usually smaller than the cerebrum, in some animals such as the mormyrid fishes it may be as large as or even larger. In humans, the cerebellum plays an important role in motor control. It may also be involved in some cognitive functions such as attention and language as well as emotional control such as regulating fear and pleasure responses, but its movement-related functions are the most solidly established. The human cerebellum does not initiate movement, but contributes to coordination, precision, and accurate timing: it receives input from sensory systems of the spinal cord and from other parts of the brain, and integrates these inputs to fine-tune motor activity. Cerebellar damage produces disorders in fine movement, equilibrium, posture, and motor learning in humans. Anatomically, the human cerebellum has the appearance of a separate structure attached to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Occipital Lobe
The occipital lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The name derives from its position at the back of the head, from the Latin ''ob'', "behind", and ''caput'', "head". The occipital lobe is the visual processing center of the mammalian brain containing most of the anatomical region of the visual cortex. The primary visual cortex is Brodmann area 17, commonly called V1 (visual one). Human V1 is located on the medial side of the occipital lobe within the calcarine sulcus; the full extent of V1 often continues onto the occipital pole. V1 is often also called striate cortex because it can be identified by a large stripe of myelin, the Stria of Gennari. Visually driven regions outside V1 are called extrastriate cortex. There are many extrastriate regions, and these are specialized for different visual tasks, such as visuospatial processing, color differentiation, and motion perception. Bilateral lesions of the occipital lobe can l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tentorium Cerebelli
The cerebellar tentorium or tentorium cerebelli (Latin for "tent of the cerebellum") is an extension of the dura mater that separates the cerebellum from the inferior portion of the occipital lobes. Structure The cerebellar tentorium is an arched lamina, elevated in the middle, and inclining downward toward the circumference. It covers the top of the cerebellum, and supports the occipital lobes of the brain. Its anterior border is free and concave, and bounds a large oval opening, the tentorial incisure, through which pass the cerebral peduncles. It is attached, behind, by its convex border, to the transverse ridges upon the inner surface of the occipital bone, and there encloses the transverse sinuses; in front, to the superior angle of the petrous part of the temporal bone on either side, enclosing the superior petrosal sinuses. At the apex of the petrous part of the temporal bone the free and attached borders meet, and, crossing one another, are continued forward to be fix ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Occipital Protuberance
Along the internal surface of the occipital bone, at the point of intersection of the four divisions of the cruciform eminence, is the internal occipital protuberance. Running transversely on either side is a groove for the transverse sinus. Additional images See also * External occipital protuberance Near the middle of the squamous part of occipital bone is the external occipital protuberance, the highest point of which is referred to as the inion. The inion is the most prominent projection of the protuberance which is located at the posterioi ... References External links * Diagram at uni-mainz.de Bones of the head and neck {{musculoskeletal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crista Galli
The crista galli (Latin: "crest of the rooster") is the upper part of the perpendicular plate of the ethmoid bone of the skull. It rises above the cribriform plate. The falx cerebri (a fold of the dura mater surrounding the brain) attaches to the crista galli. Structure The crista galli is the upper part of the perpendicular plate of the ethmoid bone of the skull. It rises above the cribriform plate. The falx cerebri (a fold of the dura mater surrounding the brain) attaches to the crista galli. The olfactory bulbs of the olfactory nerve lie on either side of the crista galli on top of the cribriform plate. Variation in Morphology The base of crista galli varies in height. A retrospective study of CT data from 2007 to 2009 reviewed scans of 99 people. The results showed that in 63.6% of subjects the base extended less than 50% below the height of the cribriform plate. In 28.3%, the base did not extend above the cribriform plate, while in 8.1%, the base extended more than 50% ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frontal Bone
The frontal bone is a bone in the human skull. The bone consists of two portions.'' Gray's Anatomy'' (1918) These are the vertically oriented squamous part, and the horizontally oriented orbital part, making up the bony part of the forehead, part of the bony orbital cavity holding the eye, and part of the bony part of the nose respectively. The name comes from the Latin word ''frons'' (meaning " forehead"). Structure of the frontal bone The frontal bone is made up of two main parts. These are the squamous part, and the orbital part. The squamous part marks the vertical, flat, and also the biggest part, and the main region of the forehead. The orbital part is the horizontal and second biggest region of the frontal bone. It enters into the formation of the roofs of the orbital and nasal cavities. Sometimes a third part is included as the nasal part of the frontal bone, and sometimes this is included with the squamous part. The nasal part is between the brow ridges, and ends ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebral Hemisphere
The vertebrate cerebrum (brain) is formed by two cerebral hemispheres that are separated by a groove, the longitudinal fissure. The brain can thus be described as being divided into left and right cerebral hemispheres. Each of these hemispheres has an outer layer of grey matter, the cerebral cortex, that is supported by an inner layer of white matter. In eutherian (placental) mammals, the hemispheres are linked by the corpus callosum, a very large bundle of nerve fibers. Smaller commissures, including the anterior commissure, the posterior commissure and the fornix, also join the hemispheres and these are also present in other vertebrates. These commissures transfer information between the two hemispheres to coordinate localized functions. There are three known poles of the cerebral hemispheres: the '' occipital pole'', the '' frontal pole'', and the '' temporal pole''. The central sulcus is a prominent fissure which separates the parietal lobe from the frontal lobe and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Frontal Bone")
_-_inferiror_view.png "Click for more on -> Cerebral Hemisphere")