 Are you drooling? Can you taste it? A hard chocolate crust gives way to deeper, richer chocolate and whipped hazelnut cream. Complex flavors blend it into something absolutely delicious. The nerves that cause salivation and that carry taste as well as sensation from your mouth all travel through an area of the head called the infratemporal fossa. The infratemporal fossa acts as a relay station for many of the nerves traveling to and from the oral cavity and the lower half of the face. It might just be my favorite fossa. The major nerve of the infratemporal fossa is V3 or the mandibular branch of the trigeminal nerve. Let's have a look at the general arrangement of the mandibular nerve in the infratemporal fossa. In this sketch, the mandibular nerve enters the infratemporal fossa through the fremen ovale. The lingual nerve carries general sensation from the tongue. The inferior alveolar nerve carries general sensation from the mandibular region, including the lower teeth. And the auriculotemporal nerve carries general sensation from the temporal region. Let's now see how parasympathetic branches of 7 and 9 join the mandibular nerve. All salivary glands below the level of the oral fissure are innervated by parasympathetic fibers in a branch of 7 called corded timpani that emerges from the skull and travels to join the lingual nerve. The ganglion for corded timpani hangs off the lingual nerve in the floor of the oral cavity. Interestingly, taste from the anterior two-thirds of the tongue follows corded timpani back to the brainstem. You'll notice we still need to get parasympathetic innervation to the major salivary gland, the parataglan. These fibers are carried in a branch of 9, the lesser patrosal nerve, that enters the infratemporal fossa through the fremen ovale. The ganglion for these fibers is also associated with a vent branch of V3. Post-ganglionic fibers travel with the auriculotemporal nerve to reach the parataglan. Now let's look at some of these details in a dissection of the infratemporal fossa. In this dissection of the infratemporal fossa, the ramus of the mandible, zygomatic arch, and some musculature have been removed to expose the nerves. Here is the lingual nerve. Here is the inferior alveolar nerve. This is corda timpani, a branch of 7 joining the lingual nerve. And here is its ganglion, the submandibular ganglion. This is the major salivary gland in the head, the parataglan. The lesser patrosal nerve, which carries parasympathetic fibers from cranial nerve 9, joins the auriculotemporal nerve to reach the parataglan. So as you could see, the infratemporal fossa plays a huge role in the enjoyment of this cake. You can feel the cake's texture with your lingual nerve, taste it with corda timpani, and moisten it with the parasympathetic fibers of 7 and 9 that joined branches of 5.