Branchial motor (special visceral efferent) neurons. Innervation is accomplished via the trigeminal, facial, glossopharyngeal, vagus, and spinal accessory nerves (CNN V, VII, IX, X, and XI, respectively).
- 1 What are cranial motor neurons?
- 2 Which of the 12 cranial nerves are motor?
- 3 What does cranial nerve V innervate?
- 4 Which nerve innervates the skin of the upper eyelid?
- 5 Where are motor neurons?
- 6 Are cranial nerves motor neurons?
- 7 Do cranial nerves contain upper motor neurons?
- 8 What is an example of a motor neuron?
- 9 What are the 14 cranial nerves?
- 10 What are the 12 cranial nerves called?
- 11 Which of the following cranial nerve is not a motor nerve?
- 12 What is cranial nerve VII?
- 13 What is 6th cranial nerve?
- 14 Is the abducens nerve sensory or motor?
What are cranial motor neurons?
Main. In humans, the cell bodies of cranial motor neurons lie in the brainstem, and their axons extend through the cranial nerves to control muscles in the head and neck. Developing motor axons perform a spectacular feat, navigating over long distances from the CNS to their targets in the periphery.
Which of the 12 cranial nerves are motor?
The oculomotor nerve (III) and the trochlear nerve (IV) emerge from the mesencephalon. The CNs V to XII originate from the pons (bridge) and the medulla oblongata (extended spinal cord). The CNs III, IV, VI, XI, and XII are mainly motor nerves and provide innervation of the skeletal muscles.
What does cranial nerve V innervate?
The trigeminal nerve is the fifth cranial nerve (CN V). Its primary function is to provide sensory and motor innervation to the face. The trigeminal nerve consists of three branches on either side that extend to different territories of the face.
Which nerve innervates the skin of the upper eyelid?
The oculomotor nerve (CNIII) innervates the main upper eyelid retractor, the levator palpebrae superiorus, via its superior branch.
Where are motor neurons?
Motor neurons (MNs) are neuronal cells located in the central nervous system (CNS) controlling a variety of downstream targets. There are two main types of MNs, (i) upper MNs that originate from the cerebral cortex and (ii) lower MNs that are located in the brainstem and spinal cord.
Are cranial nerves motor neurons?
Lower motor neurons (LMNs) are motor neurons located in either the anterior grey column, anterior nerve roots (spinal lower motor neurons) or the cranial nerve nuclei of the brainstem and cranial nerves with motor function (cranial nerve lower motor neurons).
Do cranial nerves contain upper motor neurons?
For cranial nerves, cell bodies of upper motor neurons are in the head and neck area of the motor cortex. The term upper motor neurons is also used clinically to include fibres from other brain centres (e.g. parietal lobe, basal ganglia, cerebellum, reticular formation, midbrain, etc.)
What is an example of a motor neuron?
For example, the medial motor column (MMC) consists of motor neurons that innervate long muscles of the back (MMCm) and motor neurons that innervate body wall musculature (MMCl). The MMC motor neurons are generated throughout the cervical, thoracic, and lumbar spinal cord.
What are the 14 cranial nerves?
The nerves are: the olfactory nerve (I), the optic nerve (II), oculomotor nerve (III), trochlear nerve (IV), trigeminal nerve (V), abducens nerve (VI), facial nerve (VII), vestibulocochlear nerve (VIII), glossopharyngeal nerve (IX), vagus nerve (X), accessory nerve (XI), and the hypoglossal nerve (XII).
What are the 12 cranial nerves called?
The twelve cranial nerves, in order from I to XII are: olfactory nerve, optic nerve, oculomotor nerve, trochlear nerve, trigeminal nerve, abducens nerve, facial nerve, vestibulocochlear nerve, glossopharengeal nerve, vagus nerve, spinal accessory nerve, and hypoglossal nerve.
Which of the following cranial nerve is not a motor nerve?
Optic nerve is not a motor nerve.
What is cranial nerve VII?
The facial nerve is the seventh cranial nerve (CN VII). The facial nerve provides motor innervation of facial muscles that are responsible for facial expression, parasympathetic innervation of the glands of the oral cavity and the lacrimal gland, and sensory innervation of the anterior two-thirds of the tongue.
What is 6th cranial nerve?
Cranial nerve six (CN VI), also known as the abducens nerve, is one of the nerves responsible for the extraocular motor functions of the eye, along with the oculomotor nerve (CN III) and the trochlear nerve (CN IV).
Is the abducens nerve sensory or motor?
The trochlear, abducens, accessory, and hypoglossal nerves are only motor nerves; the trigeminal nerve is both sensory and motor; the oculomotor nerve is both motor and parasympathetic; the facial glossopharyngeal, and vagus nerves have sensory, motor, and parasympathetic components (Standring, 2008).