The cranial nerves

2013 ◽  
Author(s):  
Martin E. Atkinson
Keyword(s):  
Head And Neck ◽  
Cranial Nerves ◽  
Dental Students ◽  
The Body ◽  
Neural Function ◽  
Nerve Supply ◽  
Spinal Nerves ◽  
Complete Detail ◽  
And Function ◽  
The Brain

The cranial nerves are the most important neural structures relevant to dental students and practitioners. The cranial nerves are the nerve supply to all the structures in the head and neck and underpin of the anatomy and function of these regions—the head and neck will not work without them. In a wider context, correct functioning of the cranial nerves is a very good indicator of the health or otherwise of the CNS; it may be necessary to test the function of some, or even all, of the cranial nerves at times to assess neural function. In addition, many of the cranial nerves may be involved in various diseases of the head and neck. As outlined in Chapter 3, 12 pairs of cranial nerves arising from the brain form one major component of the peripheral nervous system, the 31 pairs of spinal nerves forming the other. Each pair of cranial nerves has a name and number. Conventionally, they are numbered using the Roman numerals I to XII. The nerves are numbered from one to 12, according to their origin from the brain; nerves with the lowest numbers arise from the most anterior aspect of the brain (the forebrain) whereas those with highest numbers arise from the lowest part (the medulla). Several aspects of any nerve anywhere in the body are required to d escribe its anatomy and function in complete detail: • Its origins and terminations in the CNS; • Its neuronal components—are they motor, sensory, or autonomic? • Its course to and from its target tissues; • Its distribution to specific areas and structures through specific branches; • Its overall functions and specific functions of its component parts. In addition, if the clinical significance is going to be appreciated, we w ill also need to consider: • The effects of damage or disease on the nerve; • Its important relationships to other structures; • How to test whether the nerve is functioning correctly. Given that there are 12 pairs of nerves, does a competent dentist need to know everything in the two lists about every cranial nerve? The answer, you will be relieved to hear, is ‘no’.

scholarly journals I. On the relation between the structure, function, and distribution of the cranial nerves. Preliminary communication

1888 ◽  
Vol 43 (258-265) ◽  
pp. 382-390 ◽  
Keyword(s):  
Spinal Cord ◽  
Structure Function ◽  
External Surface ◽  
Cranial Nerves ◽  
The Body ◽  
Spinal Nerves ◽  
Internal Surfaces ◽  
Preliminary Communication ◽  
And Function ◽  
Lateral Plates

In a previous paper I have pointed out that the structure, distribution, and function of the spinal nerves, as well as the arrangement of their centres of origin in the spinal cord, all lead to the conclusion that these nerves are divisible into two parts; (1) a somatic part, supplying the external surface of the body and the muscles derived from the muscle plates, and (2) a splanchnic part, supplying the internal surfaces and organs and the muscles derived from the lateral plates of mesoblast. I also pointed out that the cranial nerves were built up on a similar plan and arose from similar centres of origin to the spinal nerves; that they too were divisible into somatic and splanchnic groups of the same type as in the spinal nerves.

scholarly journals Assessing the Role of Machine Learning in Robotics

2020 ◽  
Vol 6 (5) ◽  
pp. 13-15
Keyword(s):  
Machine Learning ◽  
The Body ◽  
Machine Learning Algorithms ◽  
Machine Learning Techniques ◽  
Robot Perception ◽  
Learning Techniques ◽  
Complete Detail ◽  
And Function ◽  
The Brain

Machine learning is concerned with algorithms inspired by the structure and function of the brain called artificial neural networks. Neural framework offers wide support for machine learning algorithms. It is an interface, library or tool which allows developers to build machine learning models easily, without getting into the depth of the underlying algorithms. The neural framework is an exceptionally intricate piece of a person that co-ordinate its activities Moreover, tactile data by transmitting signs to and from various pieces of the body. Neural frameworks are applied to perform object gathering and a grasp orchestrating task. Machine Learning techniques have been applied to many sub problems in robot perception – pattern recognition and self-organisation. Modern robot framework which demands a complete detail of each movement of the robot, which breaks the pick-and-spot issue into about free, computationally conceivable sub-issues as a phase toward a comprehensive endeavour level framework

Memoirs: Notes on the Development of the Newt (Triton Cristatus)

1886 ◽  
Vol s2-26 (104) ◽  
pp. 573-589
Author(s):  
ALICE JOHNSON ◽  
LILIAN SHELDON
Keyword(s):  
Early Stage ◽  
Cranial Nerves ◽  
Sense Organ ◽  
The Body ◽  
Front Wall ◽  
Main Trunk ◽  
Dorsal Wall ◽  
Spinal Nerves ◽  
Neural Canal ◽  
The Brain

1. A solid post-anal gut is formed behind the blastopore (anus), growing out into the tail, and fusing with the undifferentiated tissues at its posterior end. The fusion of hypoblast and epiblast in this region represents the neurenteric canal. 2. In the Frog the post-anal gut is at first hollow, but afterwards becomes solid. 3. The stomodæum and pituitary body are derived from a solid ingrowth of the inner layer of the epiblast. The hind part of this ingrowth fuses with the front wall of the fore-gut, but the perforation to form the actual mouth does not appear till after hatching. The pituitary body grows upwards as a solid cord, and applies itself to the infundibulum in the ordinary manner. 4. From the hind border of the stomodæum proceeds a solid rod of cells, which constitutes the thyroid body, and is developed from the cells of the middle ventral line of the foregut. 5. The development of the peripheral nervous system is preceded by the appearance of a neural ridge, extending along the whole length of the body. 6. The spinal nerves grow out from the neural ridge, and pass downwards between the neural canal and muscle plates. 7. The cranial nerves also grow out from the neural ridge, but are nearer to the surface than the spinal nerves, owing to the absence of muscle plates in the head. 8. When each has attained a certain length it fuses with a thickening of the epiblast, situated some distance above the level of the notochord. (This is the case with the 5th, 7th, and 9th nerves, and probably also with the vagus.) 9. At the point of fusion there is a thickening of the nervetrunk, forming a ganglion, which afterwards recedes from the surface, remaining, however, attached to the sense organ by a nerve. 10. The main trunk of the nerve passes on, and, in the cases of the 7th and 9th nerves, fuses again with the epiblast of the dorsal wall of the corresponding gill-cleft. Later, the nerve becomes detached from the epiblast, and gives off two branches, one behind and one in front of the gill-cleft. 11. The 5th nerve has no such second (ventral) fusion with the epiblast, but divides below its first (dorsal) fusion into two branches, the superior and inferior maxillary. 12. In the Frog a neural ridge is present at an early stage, just after the closure of the neural canal. The facio-auditory nerve grows out of the brain, and it is therefore probable that the other cranial nerves have the same origin. N.B.--Our figures are diagrammatic in so far that the outlines of the cells were not perfectly apparent in all sections. This appeared to us to be due to bad preservation, as the better the specimens were preserved the more distinct and complete were the cell outlines. It was generally possible to draw them accurately with a camera and Zeiss obj. D, OC. 2. We have therefore represented them throughout as distinct.

scholarly journals Culture Wires the Brain

2010 ◽  
Vol 5 (4) ◽  
pp. 391-400 ◽  
Author(s):  
Denise C. Park ◽  
Chih-Mao Huang
Keyword(s):  
Brain Structure ◽  
Cultural Psychology ◽  
Structure And Function ◽  
Neural Function ◽  
Limited Evidence ◽  
Neural Structure ◽  
Cultural Experiences ◽  
Brain Structure And Function ◽  
And Function ◽  
The Brain

There is clear evidence that sustained experiences may affect both brain structure and function. Thus, it is quite reasonable to posit that sustained exposure to a set of cultural experiences and behavioral practices will affect neural structure and function. The burgeoning field of cultural psychology has often demonstrated the subtle differences in the way individuals process information—differences that appear to be a product of cultural experiences. We review evidence that the collectivistic and individualistic biases of East Asian and Western cultures, respectively, affect neural structure and function. We conclude that there is limited evidence that cultural experiences affect brain structure and considerably more evidence that neural function is affected by culture, particularly activations in ventral visual cortex—areas associated with perceptual processing.

Morphometry in schizophrenia revisited: height and its relationship to pre-morbid function

1998 ◽  
Vol 28 (3) ◽  
pp. 655-663 ◽  
Author(s):  
P. NOPOULOS ◽  
M. FLAUM ◽  
S. ARNDT ◽  
N. ANDREASEN
Keyword(s):  
Psychosocial Adjustment ◽  
Cognitive Abilities ◽  
Economic Status ◽  
The Body ◽  
Abnormal Development ◽  
Control Group ◽  
Childhood And Adolescence ◽  
Lower Quartile ◽  
And Function ◽  
The Brain

Background. Morphometry, the measurement of forms, is an ancient practice. In particular, schizophrenic somatology was popular early in this century, but has been essentially absent from the literature for over 30 years. More recently, evidence has grown to support the notion that aberrant neurodevelopment may play a role in the pathophysiology of schizophrenia. Is the body, like the brain, affected by abnormal development in these patients?Methods. To evaluate global deficit in development and its relationship to pre-morbid function, height was compared in a large group (N=226) of male schizophrenics and a group of healthy male controls (N=142) equivalent in parental socio-economic status. Patients in the lower quartile of height were compared to those in the upper quartile of height.Results. The patient group had a mean height of 177·1 cm, which was significantly shorter than the mean height of the control group of 179·4 (P<0·003). Those in the lower quartile had significantly poorer pre-morbid function as measured by: (1) psychosocial adjustment using the pre-morbid adjustment scales for childhood and adolescence/young adulthood, and (2) cognitive function using measures of school performance such as grades and need for special education. In addition, these measures of pre-morbid function correlated significantly with height when analysed using the entire sample.Conclusions. These findings provide further support to the idea that abnormal development may play a key role in the pathophysiology of schizophrenia. Furthermore, this is manifested as a global deficit in growth and function resulting in smaller stature, poorer social skills, and deficits in cognitive abilities.

Genealogy of the Cerebral Subject

Being Brains ◽  
2017 ◽  
Author(s):  
Fernando Vidal ◽  
Francisco Ortega
Keyword(s):  
Nineteenth Century ◽  
Functional Neuroimaging ◽  
The Body ◽  
Self Help ◽  
Brain Structure And Function ◽  
Cerebral Subject ◽  
The Individual ◽  
And Function ◽  
Cerebral Self ◽  
The Brain

The first chapter proposes to trace the distant roots of the cerebral subject to the late seventeenth century, and particularly to debates about the seat of the soul, the corpuscularian theory of matter, and John Locke’s philosophy of personal identity. In the wake of Locke, eighteenth century authors began to assert that the brain is the only part of the body we need to be ourselves. In the nineteenth century, this form of deterministic essentialism contributed to motivate research into brain structure and function, and in turn confirmed the brain-personhood nexus. Since then, from phrenology to functional neuroimaging, neuroscientific knowledge and representations have constituted a powerful support for prescriptive outlooks on the individual and society. “Neuroascesis,” as we call the business that sells programs of cerebral self-discipline, is a case in point, which this chapter also examines. It appeals to the brain and neuroscience as bases for its self-help recipes to enhance memory and reasoning, fight depression, anxiety and compulsions, improve sexual performance, achieve happiness, and even establish a direct contact with God. Yet underneath the neuro surface lie beliefs and even concrete instructions that can be traced to nineteenth-century hygiene manuals.

The skull

2013 ◽  
Author(s):  
Martin E. Atkinson
Keyword(s):  
Soft Tissues ◽  
Clinical Importance ◽  
Dental Students ◽  
Structural Basis ◽  
Facial Skeleton ◽  
Lower Jaw ◽  
Temporomandibular Joints ◽  
Maxilla And Mandible ◽  
And Function ◽  
The Brain

Dental students and practitioners require a sound knowledge of the structure, growth, and development of the skull as a whole. The structure of the skull can be examined and studied more efficiently if you have access to a dried skull or one of the very good plastic replica skulls which are now available; you can identify the structures on the diagrams accompanying the following descriptions and examine a skull at the same time to appreciate the size and relationships of individual components. This chapter outlines the basic principles of the development and structure of the skull and includes some reference to individual bones where this makes understanding easier. The more detailed aspects of particular regions of the skull will be covered in the appropriate chapter describing the whole anatomy of that region; it is much easier to learn the parts of the skull in context of overall structure and function rather than learning a long list of bones, foramina, and muscle attachments in isolation from the related soft tissue structures. Only the maxilla and mandible which are bones of significant clinical importance are described as separate bones. As already demonstrated in Chapter 20, the skull is the structural basis f or the anatomy of the head. The skull has many functions. • It encloses and protects the brain. • It provides protective capsules for the eyes and middle and inner ear. • It forms the skeleton of the entrances to the respiratory and gastrointestinal tracts (GIT) through the nose and mouth, respectively. Those skull components that form the entrance to the GIT also house and support the teeth and soft tissues of the oral region as part of this function. As already outlined in Chapter 20, the skull is made up of several bones joined together to form the cranium which articulates with the separate mandible forming the lower jaw at the temporomandibular joints. The cranium specifically refers to the skull without the mandible; the terms ‘skull’ and ‘cranium’ are not strictly synonymous but they are frequently used as though they are. The cranium can be subdivided into the braincase enclosing the brain and the facial skeleton.

Amyloidosis

2013 ◽  
pp. 1397-1409
Author(s):  
Philip N. Hawkins
Keyword(s):  
Protein Misfolding ◽  
Solid Organ Transplantation ◽  
The Body ◽  
Solid Organ ◽  
Body Protein ◽  
Amyloid Deposits ◽  
Life Threatening ◽  
And Function ◽  
Protein Misfolding And Aggregation ◽  
The Brain

Amyloidosis is a disorder of protein folding in which normally soluble proteins are deposited in the interstitial space as insoluble and remarkably stable fibrils that progressively disrupt tissue structure and function of organs throughout the body. Protein misfolding and aggregation have increasingly been recognized in the pathogenesis of various other diseases, but amyloidosis—the disease directly caused by extracellular amyloid deposition—is a precise term with critical implications for patients with a specific group of life-threatening disorders. Amyloidosis may be acquired or hereditary and the pattern of organ involvement varies within and between types, though clinical phenotypes overlap greatly. Virtually any tissue other than the brain may be directly involved. Although histology remains the diagnostic gold standard, developments in scintigraphy and MRI technology often produce pathognomonic findings. Systemic amyloidosis is usually fatal, but the prognosis has improved as the result of increasingly effective treatments for many of the conditions that underlie it, notably the use of biologic anti-inflammatory agents in patients with AA amyloidosis and new immunomodulatory agents in patients with AL type. Better supportive care, including dialysis and solid organ transplantation, have also influenced the prognosis favourably. A range of specific novel therapies are currently in clinical development, including RNA inhibitors that suppress production of amyloid precursor proteins, drugs that promote their normal soluble conformation in the plasma, and immunotherapy approaches that directly target the amyloid deposits.

scholarly journals Regulatory Roles of Bone in Neurodegenerative Diseases

2020 ◽  
Vol 12 ◽  
Author(s):  
Zhengran Yu ◽  
Zemin Ling ◽  
Lin Lu ◽  
Jin Zhao ◽  
Xiang Chen ◽  
...  
Keyword(s):  
Stem Cells ◽  
Neurodegenerative Diseases ◽  
The Elderly ◽  
Lymphoid Organ ◽  
The Body ◽  
Hematopoietic Stem ◽  
Brain Functions ◽  
And Function ◽  
The Impact ◽  
The Brain

Osteoporosis and neurodegenerative diseases are two kinds of common disorders of the elderly, which often co-occur. Previous studies have shown the skeletal and central nervous systems are closely related to pathophysiology. As the main structural scaffold of the body, the bone is also a reservoir for stem cells, a primary lymphoid organ, and an important endocrine organ. It can interact with the brain through various bone-derived cells, mostly the mesenchymal and hematopoietic stem cells (HSCs). The bone marrow is also a place for generating immune cells, which could greatly influence brain functions. Finally, the proteins secreted by bones (osteokines) also play important roles in the growth and function of the brain. This article reviews the latest research studying the impact of bone-derived cells, bone-controlled immune system, and bone-secreted proteins on the brain, and evaluates how these factors are implicated in the progress of neurodegenerative diseases and their potential use in the diagnosis and treatment of these diseases.

Major sensory and motor systems

2013 ◽  
Author(s):  
Martin E. Atkinson
Keyword(s):  
Nervous System ◽  
Cerebral Cortex ◽  
No Value ◽  
Cranial Nerves ◽  
Sensory Information ◽  
The Body ◽  
Functional Responses ◽  
Motor Pathways ◽  
Sensory Pathways ◽  
And Function

The previous chapter provided an overview of the anatomy of the CNS, concentrating on structures that can be seen during dissection of the human brain and spinal cord or the study of anatomical models of these structures. Some indication of the function of different components of the CNS has been given in Chapter 15, but this chapter shows how the various anatomical components of the CNS are functionally linked together through sensory and motor pathways. These pathways enable the nervous system to convey information over considerable distances, to integrate the information, and formulate functional responses that coordinate activities of different parts of the body. It will be necessary to introduce some other structures in addition to those described in Chapter 15 during the description of major pathways; most are not visible to the naked eye and even when seen in microscopical sections, they require considerable practice to distinguish them. However, they are important landmarks or relay stations in the central nervous pathways and you need to know of them for a full understanding of pathways. As emphasized in Chapter 14, our views of the structure and function of many aspects of the nervous system are constantly subject to revision in the light of new clinical and experimental observations and methods of investigation. This applies to nerve pathways just as much as any other aspect of the nervous system. This chapter presents a summary of current views on somatic sensory and motor functions and their application to the practice of dentistry. The special sensory pathways of olfaction, vision, and hearing are described in Chapter 18 in the context of the cranial nerves that form the first part of these pathways. The information conveyed from the periphery by the sensory components of spinal and cranial nerves is destined to reach the cerebral cortex or the cerebellum. You will be conscious of sensory information that reaches the cerebral cortex, but mostly unaware of information that does not travel to the cortex. However, this does not mean that sensory information that does not attain cortical levels is of no value. For example, sensory neurons or their collateral processes form the afferent limbs of many reflex arcs.

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