@article {AhrensENEURO.0328-17.2018, author = {Allison M. Ahrens and Lindsay M. Ferguson and Terry E. Robinson and J. Wayne Aldridge}, title = {Dynamic Encoding of Incentive Salience in the Ventral Pallidum: dependence on the Form of the Reward Cue}, elocation-id = {ENEURO.0328-17.2018}, year = {2018}, doi = {10.1523/ENEURO.0328-17.2018}, publisher = {Society for Neuroscience}, abstract = {Some rats are especially prone to attribute incentive salience to a cue (conditioned stimulus, CS) paired with food reward (sign-trackers, STs), but the extent they do so varies as a function of the form of the CS. Other rats respond primarily to the predictive value of a cue (goal-trackers, GTs), regardless of its form. Sign-tracking is associated with greater cue-induced activation of mesolimbic structures than goal-tracking; however, it is unclear how the form of the CS itself influences activity in neural systems involved in incentive salience attribution. Thus, our goal was to determine how different cue modalities affect neural activity in the ventral pallidum (VP), which is known to encode incentive salience attribution, as rats performed a two-CS Pavlovian conditioned approach task in which both a lever-CS and a tone-CS predicted identical food reward. The lever-CS elicited sign-tracking in some rats (STs) and goal-tracking in others (GTs); whereas the tone-CS elicited only goal-tracking in all rats. The lever-CS elicited robust changes in neural activity (sustained tonic increases or decreases in firing) throughout the VP in STs, relative to GTs. These changes were not seen when STs were exposed to the tone-CS, and in GTs there were no differences in firing between the lever-CS and tone-CS. We conclude that neural activity throughout the VP encodes incentive signals, and is especially responsive when a cue is of a form that promotes the attribution of incentive salience to it, especially in predisposed individuals.Significance Statement The incentive-motivational value of reward-paired cues varies as a function of the individual and the form of the cue itself. Here we examined whether neural activity in a brain region important for processing reward cues, the ventral pallidum (VP), reflected variation in the incentive-motivational value of a food cue, both between individuals and between different cue types (a tone versus a manipulable lever). Neural responses were greatest in individuals that attached incentive salience to a cue, and within individuals the VP dynamically tracked changes in the motivation evoked by the different cue types. This suggests that the VP plays an important role in the encoding of the emotional/motivational states that enable cues to gain control over motivated behavior.}, URL = {https://www.eneuro.org/content/early/2018/04/25/ENEURO.0328-17.2018}, eprint = {https://www.eneuro.org/content/early/2018/04/25/ENEURO.0328-17.2018.full.pdf}, journal = {eNeuro} }