Nucleus Accumbens Neurons Are Innately Tuned for Rewarding and Aversive Taste Stimuli, Encode Their Predictors, and Are Linked to Motor Output

Department of Psychology, University of North Carolina, Chapel Hill, North Carolina 27599, USA.
Neuron (Impact Factor: 15.05). 03/2005; 45(4):587-97. DOI: 10.1016/j.neuron.2004.12.055
Source: PubMed


The nucleus accumbens (NAc) is a key component of the brain's reward pathway, yet little is known of how NAc cells respond to primary rewarding or aversive stimuli. Here, naive rats received brief intraoral infusions of sucrose and quinine paired with cues in a classical conditioning paradigm while the electrophysiological activity of individual NAc neurons was recorded. NAc neurons (102) were typically inhibited by sucrose (39 of 52, 75%) or excited by quinine (30 of 40, 75%) infusions. Changes in firing rate were correlated with the oromotor response to intraoral infusions. Most taste-responsive neurons responded to only one of the stimuli. NAc neurons developed responses to the cues paired with sucrose and quinine. Thus, NAc neurons are innately tuned to rewarding and aversive stimuli and rapidly develop responses to predictive cues. The results indicate that the output of the NAc is very different when rats taste rewarding versus aversive stimuli.

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Available from: Mitchell F Roitman, Apr 11, 2014
    • "However, laser stimulation of DS markedly increased intake despite conditioned aversion (N = 6, t [5] = 4.5, Bonferroni **P = 0.01). Overall group effect F[2,14]= 13.1, P = 0.001. (h) Optogenetic self-stimulation of VS and DS, as triggered by nose pokes (in the absence of food cues) produced equal numbers of pokes in the active versus inactive holes (ratio between pokes in active versus inactive holes is shown, DS (N = 5) versus VS (N = 6) effect t[9]= 0.76, P = 0.47). "
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