title: Taste quality decoding parallels taste sensations.
abstract: In most species, the sense of taste is key in the distinction of potentially nutritious and harmful food constituents and thereby in the acceptance (or rejection) of food. Taste quality is encoded by specialized receptors on the tongue, which detect chemicals corresponding to each of the basic tastes (sweet, salty, sour, bitter, and savory [1]), before taste quality information is transmitted via segregated neuronal fibers [2], distributed coding across neuronal fibers [3], or dynamic firing patterns [4] to the gustatory cortex in the insula. In rodents, both hardwired coding by labeled lines [2] and flexible, learning-dependent representations [5] and broadly tuned neurons [6] seem to coexist. It is currently unknown how, when, and where taste quality representations are established in the cortex and whether these representations are used for perceptual decisions. Here, we show that neuronal response patterns allow to decode which of four tastants (salty, sweet, sour, and bitter) participants tasted in a given trial by using time-resolved multivariate pattern analyses of large-scale electrophysiological brain responses. The onset of this prediction coincided with the earliest taste-evoked responses originating from the insula and opercular cortices, indicating that quality is among the first attributes of a taste represented in the central gustatory system. These response patterns correlated with perceptual decisions of taste quality: tastes that participants discriminated less accurately also evoked less discriminated brain response patterns. The results therefore provide the first evidence for a link between taste-related decision-making and the predictive value of these brain response patterns.
authors.affiliation: Institute of Medical Psychology, Charité University Medicine, Luisenstraße 57, 10117 Berlin, Germany.
authors.forename: Sébastien M
authors.initials: SM
authors.lastname: Crouzet
authors.affiliation: Institute of Medical Psychology, Charité University Medicine, Luisenstraße 57, 10117 Berlin, Germany; Berlin School of Mind and Brain, Humboldt-University, Unter den Linden 6, 10099 Berlin, Germany.
authors.forename: Niko A
authors.initials: NA
authors.lastname: Busch
authors.affiliation: Psychophysiology of Food Perception, German Institute of Human Nutrition Potsdam-Rehbruecke, Arthur-Scheunert-Allee 114-116, 14558 Nuthetal, Germany. Electronic address: kathrin.ohla@dife.de.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Ohla
mesh_terms: D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology*; D002628:Chemoreceptor Cells / Q000502:physiology*; D004594:Electrophysiology / Q000379:methods; D009474:Neurons / Q000502:physiology*; D013649:Taste / Q000502:physiology*; D055697:Taste Perception / Q000502:physiology*; D014059:Tongue / Q000502:physiology