Common carotid artery vertebral artery. The common carotid artery is often used in measuring the pulse,{ especially in patients who are in shock and who lack a detectable pulse in the more peripheral arteries of the body. The pulse is taken by palpating the artery just deep to the anterior border of the sternocleidomastoid muscle at the level of the superior border of the thyroid cartilage. Presence of a carotid pulse has been estimated to indicate a systolic blood pressure of more than 40 mmHg, as given by the 50% percentile. Carotidynia is a syndrome marked by soreness of the carotid artery near
Carotid sinus regulation of the body in sync to external conditions). The carotid sinus contains numerous baroreceptors which function as a "sampling area" for many homeostatic mechanisms for maintaining blood pressure. The carotid sinus baroreceptors are innervated by the sinus nerve of Hering, which is a branch of cranial nerve IX (glossopharyngeal nerve). The glossopharyngeal nerve synapses in the nucleus tractus solitarii (NTS) located in the medulla oblongata of the brainstem. The NTS indirectly modulates the activity of sympathetic and parasympathetic (vagal) neurons in the medulla and pons through the hypothalamus. These neurons then regulate the autonomic control of the heart and