The primary cortical processing area for taste—the part of the cortex that first receives taste information. Also called insula or gustatory cortex.
One of the four basic tastes; the taste quality produced by the hydrogen ion in acids.
A globular cluster of cells that has the function of creating neural signals conveyed to the brain by the taste nerves. Some of the cells in a taste bud have specialized sites on their apical projections that interact with taste stimuli. Some of the cells form synapses with taste nerve fibers.
taste receptor cell
A cell within the taste bud that contains sites on its apical projection that can interact with taste stimuli. These sites fall into two major categories: those interacting with charged particles (e.g., sodium and hydrogen ions), and those interacting with specific chemical structures.
retronasal olfactory sensation
The sensation of an odor that is perceived when chewing and swallowing force an odorant in the mouth up behind the palate into the nose. Such odor sensations are perceived as originating from the mouth, even though the actual contact of odorant and receptor occurs at the olfactory mucosa.
Slender projections of the cell membrane on the tips of some taste bud cells that extend into the taste pore.
specific hungers theory
The idea that deficiency of a given nutrient produces craving (a specific hunger) for that nutrient. Curt Richter first proposed this theory and demonstrated that cravings for salty or for sweet are associated with deficiencies in those substances. However, the idea proved wrong for other nutrients (e.g., vitamins).
The branch of cranial nerve VII (the facial nerve) that carries taste information from the anterior, mobile tongue (the part that can be stuck out). The chorda tympani exits the tongue with the lingual branch of the trigeminal nerve (cranial nerve V) and then passes through the middle ear on its way to the brain.
orbitofrontal cortex (OFC)
The part of the frontal lobe of the cortex that lies behind the bone (orbit) containing the eyes. The OFC is responsible for the conscious experience of olfaction, as well as the integration of pleasure and displeasure from food; and it has been referred to as the secondary olfactory cortex and secondary taste cortex. The OFC is also involved in many other functions, and it is critical for assigning affective value to stimuli—in other words, determining hedonic meaning.
A chain of two molecules.
An individual whose perception of taste sensations is the most intense. A variety of factors may contribute to this heightened perception; among the most important is the density of fungiform papillae.
One of the four basic tastes; the taste quality, generally considered unpleasant, produced by substances like quinine or caffeine.
nontaster (of PTC/PROP)
An individual born with two recessive alleles for the TAS2R38 gene and unable to taste the compounds phenylthiocarbamide and propylthiouracil.
Any stimulus that can be tasted.
The ability to match the intensities of sensations that come from different sensory modalities. This ability enables insight into sensory differences. For example, a listener might adjust the brightness of a light until it matches the loudness of a tone.
taster (of PTC/PROP)
An individual born with one or both dominant alleles for the TAS2R38 gene and able to taste the compounds phenylthiocarbamide and propylthiouracil. PTC/PROP tasters who also have a high density of fungiform papillae are PROP supertasters.
A theory of taste coding in which each taste nerve fiber carries a particular taste quality. For example, the quality evoked from a sucrose-best fiber is sweet, that from an NaCl-best fiber is salty, and so on.
Mushroom-shaped structures (maximum diameter 1 millimeter) that are distributed most densely on the edges of the tongue, especially the tip. Taste buds (an average of six per papilla) are buried in the surface.
Any of the four taste qualities that are generally agreed to describe human taste experience: sweet, salty, sour, bitter.
monosodium glutamate (MSG)
The sodium salt of glutamic acid (an amino acid).
Small structures on the tongue that provide most of the bumpy appearance. Filiform papillae have no taste function.
A chain of two molecules that are different from each other.
The combination of true taste (sweet, salty, sour, bitter) and retronasal olfaction.
One of the four basic tastes; the taste quality produced by some sugars, such as glucose, fructose, and sucrose. These three sugars are particularly biologically useful to us, and our sweet receptors are tuned to them. Some other compounds (e.g., saccharin, aspartame) are also sweet.
The taste sensation produced by monosodium glutamate.
One of the four basic tastes; the taste quality produced by the cations of salts (e.g., the sodium in sodium chloride produces the salty taste). Some cations also produce other taste qualities (e.g., potassium tastes bitter as well as salty). The purest salty taste is produced by sodium chloride (NaCl), common table salt.
Twelve pairs of nerves (one for each side of the body) that originate in the brain stem and reach sense organs and muscles through openings in the skull.
Folds of tissue containing taste buds. Foliate papillae are located on the rear of the tongue lateral to the circumvallate papillae, where the tongue attaches to the mouth.
Circular structures that form an inverted V on the rear of the tongue (three to five on each side, with the largest in the center). Circumvallate papillae are moundlike structures surrounded by a trench (like a moat). These papillae are much larger than fungiform papillae.
Any of multiple structures that give the tongue its bumpy appearance. From smallest to largest, the papilla types that contain taste buds are fungiform, foliate, and circumvallate; filiform papillae, which do not contain taste buds, are the smallest and most numerous.