Organization of taste-evoked activity in the hamster parabrachial nucleus

Small groups of 3-4 neighboring taste neurons in the hamster parabrachial nucleus (PBN) were either generalists (42%) or specialists (58%). Generalists responded well to sucrose, NaCl, KCl, and their mixture but specialists responded to only one or two stimuli. PBN temporal response patterns resembled chorda tympani patterns, indicating that they were preserved across two synapses. Generalist neuron-groups were distributed throughout the central medial (CM) subdivision of PBN. Sucrose-sensitive neuron-groups, which responded best to mixtures, were restricted to rostral CM, whereas most NaCl-best neuron groups were in caudal CM. These results suggest a multifaceted functional organization of taste sensibilities in the PBN.