circumvallate

Circumvallate papillae, also known as vallate papillae, are one of the four major types of papillae on the human tongue. They are large and dome-shaped, typically numbering about 8–12, and arranged in a single inverted V-shaped row just anterior to the sulcus terminalis near the posterior portion of the tongue.

Each circumvallate papilla is surrounded by a circular trench or groove, forming a wall around it. The taste buds are located mainly on the lateral surfaces within the trench, while the central area between papillae is relatively smooth. The mouths of the von Ebner’s glands drain serous fluid into the trenches to wash away tastants and help clear residue between exposures to new flavors.

Histologically, circumvallate papillae consist of stratified squamous epithelium over a core of connective tissue. Taste receptor cells within the taste buds extend microvilli into the gustatory pores and transduce chemical stimuli into neural signals.

Innervation for circumvallate papillae involves the glossopharyngeal nerve (CN IX), which carries gustatory fibers from these papillae to the brainstem. General somatic sensation from the vallate region is also supplied by CN IX, while the anterior two-thirds of the tongue are mainly served by the lingual nerve (a branch of V3).

Functionally, circumvallate papillae contribute to the sense of taste, with their taste buds playing a prominent role in gustatory perception, particularly for stimuli that engage the posterior tongue. They are distinct from other papillae types in structure, innervation, and arrangement.