Behavioral support for a neural taste theory

The time required for rats to make a behavioral taste discrimination was predicted from neural discharge rates and tested using conditioned aversion. Predictions were based on the hypothesis that the responses evoked from a neural population by two different chemicals must diverge by a certain critical total number of spikes before the chemicals are discriminable. This total could be derived from the responses of all neurons in the population. Behavioral discrimination times generally supported predictions made from second-order (bulbar) neural responses, but were ambiguous concerning predictions based on fourth-order (thalamic) responses. The implications of these results for the possible functions of bulbar and thalamic taste neurons is discussed.