Coding of gustatory information in the pontine parabrachial nuclei of the rabbit: temporal patterns of neural response.
As an extension of the analysis of magnitude of response to gustatory stimuli in the parabrachial nuclei5, this study sought to determine to what extent time course of neural response coded information about taste quality. A principal components analysis and stepwise discriminant analysis were used to evaluate stimulus-related differences in time course of response. Temporal patterns of response over an 8.192 s period to the 4 basic types of taste stimuli were discriminated from one another at about twice chance level. The discrimination of different qualities of taste by time course exceeded discrimination of different intensities of the stimuli. Analysis of time course restricted to the first 2,048 s of response again revealed significant overall differentiation of the stimuli, but only NaCl and sucrose were individually discriminated. Temporally coded information about gustatory stimuli, particularly in terms of onset characteristics of response, appeared inadequate for perceptual differentiation of taste quality. Such coding might, however, complement an across-neuron spatial pattern code for taste quality in simplifying the decoding of taste input for control of reflexive responses that entail a more inclusive classification of taste stimuli.
D000818:Animals; D009474:Neurons / Q000502:physiology*; D010812:Physical Stimulation; D011149:Pons / Q000502:physiology*; D011817:Rabbits; D012965:Sodium Chloride; D013395:Sucrose; D013649:Taste
D012965:Sodium Chloride; D013395:Sucrose