Chapter 16 - Section 16.3 - Study Guide - Assess Your Learning Outcomes - Page 625: 5

Taste signals from the tongue and oral cavity are transmitted to the brain through several cranial nerves, specifically the facial nerve (cranial nerve VII), glossopharyngeal nerve (cranial nerve IX), and vagus nerve (cranial nerve X). These nerves carry taste information to different brain regions via different routes: 1. **Facial Nerve (Cranial Nerve VII):** - Carries Taste Signals from: The anterior two-thirds of the tongue, including the fungiform and anterior foliate papillae. - Route to the Brain: The taste signals carried by the facial nerve travel through the geniculate ganglion and then through the chorda tympani branch of the facial nerve. The chorda tympani joins with the lingual branch of the mandibular division of the trigeminal nerve (cranial nerve V3). The taste signals then travel to the brainstem. 2. **Glossopharyngeal Nerve (Cranial Nerve IX):** - Carries Taste Signals from: The posterior one-third of the tongue, including the circumvallate papillae. - Route to the Brain: Taste signals carried by the glossopharyngeal nerve travel through the petrosal ganglion and then enter the brainstem. They eventually reach the nucleus of the solitary tract (NST) in the medulla oblongata. 3. **Vagus Nerve (Cranial Nerve X):** - Carries Taste Signals from: The epiglottis and the back of the throat (pharynx). - Route to the Brain: Taste signals carried by the vagus nerve travel to the NST in the medulla oblongata. The nucleus of the solitary tract (NST) in the medulla oblongata serves as the primary relay center for taste information. From the NST, taste signals are further transmitted to other brain regions, including the thalamus and the gustatory cortex in the brain's cerebral cortex. The thalamus plays a crucial role in relaying taste information to the gustatory cortex, where taste perception and recognition occur. The gustatory cortex is located in the insular cortex, which is a folded region within the cerebral cortex. The insular cortex is responsible for processing and integrating taste information with other sensory inputs, as well as with cognitive and emotional factors. The combined processing of taste, smell (aroma), and other sensory cues contributes to the overall perception of flavor. In summary, taste signals are carried by the facial, glossopharyngeal, and vagus nerves to the nucleus of the solitary tract in the medulla oblongata. From there, these signals are relayed to the thalamus and ultimately reach the gustatory cortex in the insular cortex, where the perception of taste and flavor occurs.

Taste signals from the tongue and oral cavity are transmitted to the brain through several cranial nerves, specifically the facial nerve (cranial nerve VII), glossopharyngeal nerve (cranial nerve IX), and vagus nerve (cranial nerve X). These nerves carry taste information to different brain regions via different routes: 1. **Facial Nerve (Cranial Nerve VII):** - Carries Taste Signals from: The anterior two-thirds of the tongue, including the fungiform and anterior foliate papillae. - Route to the Brain: The taste signals carried by the facial nerve travel through the geniculate ganglion and then through the chorda tympani branch of the facial nerve. The chorda tympani joins with the lingual branch of the mandibular division of the trigeminal nerve (cranial nerve V3). The taste signals then travel to the brainstem. 2. **Glossopharyngeal Nerve (Cranial Nerve IX):** - Carries Taste Signals from: The posterior one-third of the tongue, including the circumvallate papillae. - Route to the Brain: Taste signals carried by the glossopharyngeal nerve travel through the petrosal ganglion and then enter the brainstem. They eventually reach the nucleus of the solitary tract (NST) in the medulla oblongata. 3. **Vagus Nerve (Cranial Nerve X):** - Carries Taste Signals from: The epiglottis and the back of the throat (pharynx). - Route to the Brain: Taste signals carried by the vagus nerve travel to the NST in the medulla oblongata. The nucleus of the solitary tract (NST) in the medulla oblongata serves as the primary relay center for taste information. From the NST, taste signals are further transmitted to other brain regions, including the thalamus and the gustatory cortex in the brain's cerebral cortex. The thalamus plays a crucial role in relaying taste information to the gustatory cortex, where taste perception and recognition occur. The gustatory cortex is located in the insular cortex, which is a folded region within the cerebral cortex. The insular cortex is responsible for processing and integrating taste information with other sensory inputs, as well as with cognitive and emotional factors. The combined processing of taste, smell (aroma), and other sensory cues contributes to the overall perception of flavor. In summary, taste signals are carried by the facial, glossopharyngeal, and vagus nerves to the nucleus of the solitary tract in the medulla oblongata. From there, these signals are relayed to the thalamus and ultimately reach the gustatory cortex in the insular cortex, where the perception of taste and flavor occurs.