The vagus nerve primarily targets autonomic ganglia in the thoracic and upper abdominal cavities. Visit this site to read about a man who wakes with a headache and a loss of vision. His regular doctor sent him to an ophthalmologist to address the vision loss.
The ophthalmologist recognizes a greater problem and immediately sends him to the emergency room. Once there, the patient undergoes a large battery of tests, but a definite cause cannot be found. A specialist recognizes the problem as meningitis, but the question is what caused it originally.
How can that be cured? The loss of vision comes from swelling around the optic nerve, which probably presented as a bulge on the inside of the eye. Why is swelling related to meningitis going to push on the optic nerve? Another important aspect of the cranial nerves that lends itself to a mnemonic is the functional role each nerve plays.
The nerves fall into one of three basic groups. They are sensory, motor, or both see Table The remainder of the nerves contain both sensory and motor fibers. The nerves that convey both are often related to each other. The trigeminal and facial nerves both concern the face; one concerns the sensations and the other concerns the muscle movements.
The facial and glossopharyngeal nerves are both responsible for conveying gustatory, or taste, sensations as well as controlling salivary glands. The vagus nerve is involved in visceral responses to taste, namely the gag reflex. This is not an exhaustive list of what these combination nerves do, but there is a thread of relation between them. Skip to content Spinal Nerves The nerves connected to the spinal cord are the spinal nerves.
Figure The cervical plexus supplies nerves to the posterior head and neck, as well as to the diaphragm. The brachial plexus supplies nerves to the arm. The lumbar plexus supplies nerves to the anterior leg. The sacral plexus supplies nerves to the posterior leg.
Cranial Nerves The nerves attached to the brain are the cranial nerves, which are primarily responsible for the sensory and motor functions of the head and neck one of these nerves targets organs in the thoracic and abdominal cavities as part of the parasympathetic nervous system. External Website Visit this site to read about a man who wakes with a headache and a loss of vision. Previous: Next: Share This Book Share on Twitter. Extraocular muscles other 4 , levator palpebrae superioris, ciliary ganglion autonomic.
Facial nucleus, solitary nucleus, superior salivatory nucleus. The sciatic nerve and its branches receive their blood supply from the following two sources 2 :. The extrinsic and intrinsic systems connect at various junction points. Typical variations in sciatic nerve anatomy are described below 2 :. In the above cases where the sciatic nerve divides, both portions of the nerve immediately merge again and course downward as a single nerve.
The sciatic nerve is usually undivided and leaves the pelvis through the greater sciatic foramen below the piriformis muscle left. Sometimes, the nerve may be divided, with one part passing through the piriformis and the other below the muscle right.
The sciatic nerve is a major component of the human body, supplying motor function to move each leg and foot in multiple directions as well as sensory functions along the path of the nerve and its extensions. All about L5-S1 Lumbosacral Joint. Causes of Leg Pain and Foot Pain.
You are here Conditions Spine Anatomy. Sciatic Nerve Anatomy share pin it Newsletters. Peer Reviewed. The sciatic nerve is formed in the lower spine by the combination of motor and sensory fibers from spinal nerves L4 to S3. These spinal nerves belong to a larger group of nerves in the lower spine called the lumbosacral plexus.
This long, thick, and bulky nerve runs along the back of the thigh and leg and terminates in the foot. The nerve supplies most areas of the thigh, leg, and foot. Sciatic Nerve Anatomy Video Save. Watch Sciatica Overview Video. Davis D, Vasudevan A. The lumbosacral plexus which innervates the pelvic limb and pelvis, is formed by ventral branches of spinal nerves L4 to S3 in the carnivore.
These ventral branches exchange axons and give rise to individual nerves that contain axons from multiple segments. The lumbar portion of the lumbosacral plexus is located inside sublumbar musculature. Innervation of the pelvic limb may be summarized as follows: The obturator n. The femoral n. All remaining muscles of the limb are innervated by the sciatic n.
After sending branches to the hamstring muscles, the sciatic innervates muscles of the crus with two branches: the tibial n.
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