Head, neck and vertebral column
David Heylings, Stephen Carmichael, Samuel Leinster, Janak Saada, Bari M. Logan, Ralph T. Hutchings in McMinn’s Concise Human Anatomy, 2017
Brainstem - extends down from the central part of the cerebrum (Figs.3.7-3.11) and consists from above downwards of the midbrain, pons and medulla oblongata. In the brainstem are groups of nerve cells (cranial nerve nuclei), which either give rise to the motor (efferent) fibres of cranial nerves (p. 52) or receive sensory (afferent) fibres from cranial nerve ganglia, situated on the nerves outside the brainstem (corresponding to the posterior root ganglia of spinal nerves, p. 59). Among the fibres that pass through the brainstem to and from other parts of the brain and spinal cord are the motor fibres from the cerebral cortex. They become grouped together to form a bulge, the pyramid, on either side of the midline of the medulla; here, most of the fibres cross to the opposite side (motor decussation or decussation of the pyramids) to form the lateral corticospinal tract that continues into the spinal cord (p. 58).
ENTRIES A–Z
Philip Winn in Dictionary of Biological Psychology, 2003
During development of the hindbrain, the central canal of the embryonic VENTRICULAR SYSTEM enlarges to form the fourth ventricle. In the course of this development, the fourth ventricle opens and expands laterally with the consequence that sensory nuclei of the CRANIAL NERVES of the hindbrain move to a lateral rather than the dorsal position seen in the SPINAL CORD. Similarly, the motor nuclei assume a medial rather than ventral position. This developmental process is a major feature critical to an understanding of the topography and organization of cranial nerve nuclei in the hindbrain. During this process, the roof of the fourth ventricle becomes very thin as it is formed by a layer of ependyma and PIA MATER. The cerebellum eventually expands to lie over and cover the roof of the ventricle in the adult.
Degenerative Diseases of the Nervous System
Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw in Hankey's Clinical Neurology, 2020
A characteristic feature of SCA1 pathology is the atrophy and loss of Purkinje's cells from the cerebellar cortex. As SCA1 progresses, pathology is noted in other regions of the brain, including the deep cerebellar nuclei, especially the dentate nucleus, inferior olive, pons, and red nuclei. Cranial nerve nuclei III, X, and XII can also show signs of pathology. A pathologic hallmark of SCA1, as well as most of the other polyglutamine disorders, is the presence of the large inclusions containing the mutant polyglutamine protein. Besides containing mutant ATXN1, the inclusions are positive for ubiquitin and components of the proteasome and chaperone systems.
Duane Retraction Syndrome: Clinical Features and a Case Group-Specific Surgical Approach
Published in Seminars in Ophthalmology, 2019
Abuzer Gunduz, Ercan Ozsoy, Pamuk Betul Ulucan
Duane retraction syndrome (DRS) is a congenital ocular movement disorder characterized by moderate-to-severe limitation in abduction and/or adduction, as well as narrowing of the palpebral fissure, globe retraction, and vertical deviation of the affected eye on adduction.1 There is often a congenital anomaly of the sixth cranial nerve nuclei, with aberrant innervation supplied from the third cranial nerve.2 DRS is the most common form of congenital cranial dysinnervation disorders .3 It has an incidence of approximately 0.1% of the general population and accounts for 1–5% of all strabismus cases.4,5 DRS is primarily unilateral, although it presents bilaterally in 15% of all DRS patients.6 DRS type I is characterized by limited abduction, type II by limited adduction, and type III by limited abduction and adduction.7
Disorders of vision in multiple sclerosis
Published in Clinical and Experimental Optometry, 2022
Roshan Dhanapalaratnam, Maria Markoulli, Arun V Krishnan
The supranuclear control of ocular movements is a complex but elegant network receiving input from the brainstem, cranial nerve nuclei, thalamus, basal ganglia and the cerebrum, as well as the vestibulocerebellar system.79 Such is the complexity of the network that several components are responsible for a single eye movement. Frontal eye field regions of the cortex are responsible for central primary gaze and a lesion in this area may result in an ipsilateral gaze deviation.80 Saccades are rapid intentional movements of the eyes to follow targets in the environment and can also be assessed when triggered by testing the vestibuloocular reflex (VOR), which keeps the eyes fixed on a target whilst the head is in motion. In contrast, pursuit is the ability to hold a steady gaze during motion.
Application of the Scale for the Assessment and Rating of Ataxia (SARA) in pediatric oncology patients: A multicenter study
Published in Pediatric Hematology and Oncology, 2020
Daniele Panzeri, Micol Sara Bettinelli, Emilia Biffi, Francesca Rossi, Chiara Pellegrini, Nicoletta Orsini, Veronica Recchiuti, Maura Massimino, Geraldina Poggi
The main motor symptom resulting from PCF tumors is ataxia which is associated with erroneous muscle tone modulation (frequently in the direction of hypotonia), dysmetria and coordination difficulties, lack of balance and nystagmus. This can heavily affect gait and posture (static and dynamic balance, walking) as well as upper limb activities, including manipulation. Moreover, tumor itself or surgery can cause secondary motor signs such as cranial nerve malfunctioning (due to the involvement of cranial nerve nuclei) or pyramidal syndromes (due to compression of pyramidal tracts at the brain stem level).5
Related Knowledge Centers
- Axon
- Brainstem
- Nucleus
- Synapse
- Trochlear Nerve
- Spinal Cord
- Neuron
- Grey Matter
- Cranial Nerves
- General Somatic Efferent Fibers