Introduction The vagus nerve, also known as the 10th cranial nerve or CN X, is one of the longest and most complex nerves in the human body. It starts in the brainstem, travels through the neck, chest, and abdomen, and branches out to the heart, lungs, digestive tract, and even the tongue and ears. The…
Introduction The accessory nerve, also known as cranial nerve XI (CN XI), is one of the 12 cranial nerves in humans. It is considered a motor nerve and primarily innervates the sternocleidomastoid and trapezius muscles, which play crucial roles in head and shoulder movements. It has a cranial and a spinal component, though there is…
What is an Oculomotor Nerve Palsy? An eye condition called oculomotor nerve palsy or oculomotor neuropathy is caused by injury to the third cranial nerve or one of its branches. As the name indicates, the oculomotor nerve provides the majority of the muscles regulating eye movements (four of the six extraocular muscles, excluding only the lateral…
Introduction The glossopharyngeal nerve is also called the ninth cranial nerve (CN IX). It is one of the four cranial nerves, that perform sensory, motor, and parasympathetic functions. It starts from the medulla oblongata and ends in the pharynx. The glossopharyngeal nerve has multiple branches. The tympanic branch supplies the middle ear. The stylopharyngeal branch…
Introduction The vestibulocochlear nerve is also called cranial nerve eight (CN VIII). The vestibulocochlear nerve (CN VIII) connects the vestibular and cochlear nerves. It is situated within the internal auditory meatus (internal auditory canal). The cochlear nerve controls hearing, while the vestibular nerve controls balance and eye movements. CN VIII injuries are caused by pathological…
Radial Nerve Anatomy The radial nerve is a peripheral nerve that supplies specific regions of the arm, wrist, hand, and forearm (see Image). posterior nerves of the upper extremities. This nerve functions as a sensory and motor nerve. The extrinsic wrist and hand extensors, posterior forearm muscles, and posterior arm muscles are all triggered by…
A Cranial Nerve Disorder is a dysfunction of one of the twelve cranial nerves, which originate at the base of the brain, travel via openings in the skull, and supply various areas of the head, neck, and trunk. These conditions can result in facial paralysis, tingling, numbness, weakness, or pain, including in the eyes. The cranial…
Introduction The abducens nerve, also known as the abducent nerve, controls the movement of the lateral rectus muscle, allowing your eye to rotate away from the centre of your body and look left or right. The 6th cranial nerve (CN VI) functions as the abducens. This nerve only has a motor function and not a…
Introduction The trigeminal nerve (CN V) is its fifth and largest cranial nerve. Its primary function is to provide sensory innervation to the face, which is divided into three major branches. The ophthalmic (V1), maxillary (V2), and mandibular (V3) nerves are the three branches. The trigeminal ganglia, located within the Meckel’s cave of the middle…
Introduction The trochlear nerve, or fourth cranial nerve (CN IV), acts as one of the ocular motor nerves that regulate eye movement. As the only cranial nerve with a dorsal outflow from the brainstem, the trochlear nerve, despite being the smallest, has the longest intracranial path. It starts in the midbrain and travels laterally and…
