CODING IN PERIPHERAL TASTE NERVES OF RHESUS, MACACA MULATTA, CHIMPANZEE, PAN TROGLODYTES AND COMMON MARMOSET, CALLITHRIX JACCHUS JACCHUS

In perpheral taste, the coding mechanism remains an enigma. There are two theories: the across-fiber pattern theory argues “that a particular pattern of activity across the entire ensemble of afferent fibers represents a taste quality”, while the labeled-line suggests “that activity in a particular fiber type represents a specific taste quality”. This study summarizes the results from taste nerve recordings and behavior in a number of mammalian species. It links the sweet taste quality to activity in a fixed set of taste fibers forming an S-cluster. Thus our findings seem to satisfy the definition of the labeled-line theory: “that activity in a particular fiber type represents a specific taste quality“ (Smith & Frank, 1993). However, it is possible that within the S-cluster taste information is being extracted across the fibers by the CNS.