TY - JOUR
T1 - Dynamic taste responses of parabrachial pontine neurons in awake rats
AU - Baez-Santiago, Madelyn A.
AU - Reid, Emily E.
AU - Moran, Anan
AU - Maier, Joost X.
AU - Marrero-Garcia, Yasmin
AU - Katz, Donald B.
N1 - Publisher Copyright:
© 2016 the American Physiological Society.
PY - 2016/3/1
Y1 - 2016/3/1
N2 - The parabrachial nuclei of the pons (PbN) receive almost direct input from taste buds on the tongue and control basic taste-driven behaviors. Thus it is reasonable to hypothesize that PbN neurons might respond to tastes in a manner similar to that of peripheral receptors, i.e., that these responses might be narrow and relatively “dynamics free.” On the other hand, the majority of the input to PbN descends from forebrain regions such as gustatory cortex (GC), which processes tastes with “temporal codes” in which firing reflects first the presence, then the identity, and finally the desirability of the stimulus. Therefore a reasonable alternative hypothesis is that PbN responses might be dominated by dynamics similar to those observed in GC. Here we examined simultaneously recorded single-neuron PbN (and GC) responses in awake rats receiving exposure to basic taste stimuli. We found that pontine taste responses were almost entirely confined to canonically identified taste-PbN (t-PbN). Taste-specificity was found, furthermore, to be time varying in a larger percentage of these t-PbN responses than in responses recorded from the tissue around PbN (including non-taste-PbN). Finally, these time-varying properties were a good match for those observed in simultaneously recorded GC neurons—taste-specificity appeared after an initial nonspecific burst of action potentials, and palatability emerged several hundred milliseconds later. These results suggest that the pontine taste relay is closely allied with the dynamic taste processing performed in forebrain.
AB - The parabrachial nuclei of the pons (PbN) receive almost direct input from taste buds on the tongue and control basic taste-driven behaviors. Thus it is reasonable to hypothesize that PbN neurons might respond to tastes in a manner similar to that of peripheral receptors, i.e., that these responses might be narrow and relatively “dynamics free.” On the other hand, the majority of the input to PbN descends from forebrain regions such as gustatory cortex (GC), which processes tastes with “temporal codes” in which firing reflects first the presence, then the identity, and finally the desirability of the stimulus. Therefore a reasonable alternative hypothesis is that PbN responses might be dominated by dynamics similar to those observed in GC. Here we examined simultaneously recorded single-neuron PbN (and GC) responses in awake rats receiving exposure to basic taste stimuli. We found that pontine taste responses were almost entirely confined to canonically identified taste-PbN (t-PbN). Taste-specificity was found, furthermore, to be time varying in a larger percentage of these t-PbN responses than in responses recorded from the tissue around PbN (including non-taste-PbN). Finally, these time-varying properties were a good match for those observed in simultaneously recorded GC neurons—taste-specificity appeared after an initial nonspecific burst of action potentials, and palatability emerged several hundred milliseconds later. These results suggest that the pontine taste relay is closely allied with the dynamic taste processing performed in forebrain.
KW - Gustatory cortex
KW - Parabrachial nucleus
KW - Taste processing
KW - Temporal coding
UR - http://www.scopus.com/inward/record.url?scp=84984850910&partnerID=8YFLogxK
U2 - 10.1152/jn.00311.2015
DO - 10.1152/jn.00311.2015
M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???
AN - SCOPUS:84984850910
SN - 0022-3077
VL - 115
SP - 1314
EP - 1323
JO - Journal of Neurophysiology
JF - Journal of Neurophysiology
IS - 3
ER -