Electrophysiological signatures of taste quality coding

The taste system provides important information about the edibility and makro-nutrient content of a food via differentiation between taste qualities. Specific receptors on the tongue are activated by chemicals signifying a taste quality before the signal is conveyed to the brain. How this peripheral signal is used by the central nervous system to encode taste quality is largely unknown. Taste qualities have been shown to differ in behavioral response times in humans and rodents yet the relevance of these latency differences remains unclear. We investigated the spatio-temporal properties of taste quality representations in the human cortex and whether these representations are used for perceptual decisions during different tasks. Time-resolved multivariate pattern analyses of head-surface electrophysiological brain responses evoked by tasting salty, sweet, sour, and bitter tasting solutions revealed that global neuronal response patterns allow to decode which tastant participants tasted on a given trial. Taste quality information was largely limited to the delta and theta frequency bands (