My lab focuses on understanding the neural circuits underlying reward-seeking and addictive behaviors. We use a systems-level approach that combines behavioral, pharmacological, electrophysiological, optogenetics and fiber photometry techniques in awake, freely moving animals.

Our studies focus on the nucleus accumbens, a part of the ventral striatum that projects to motor output structures of the basal ganglia. The accumbens receives input from limbic structures that process stimuli that predict rewards. These limbic structures include the basolateral amygdala, which sends glutamatergic axons to the accumbens, and the ventral tegmental area (VTA), which sends a dopamine projection. We investigate how these projections to the accumbens alter the activity of accumbens neurons to influence reward-seeking behavior.

The accumbens and associated circuitry is involved in drug addiction. A secondary focus of the lab is to understand how drugs alter neurons in these circuits to produce drug-seeking behavior.

Click here for full publication list in PubMed

Fields HL, Hjelmstad GO, Margolis EB and Nicola SM (2007) Ventral tegmental area neurons in learned appetitive behavior and positive reinforcement. Annu. Rev. Neurosci. 30:289-316.

Ishikawa A, Ambroggi F, Nicola SM and Fields HL (2008) Dorsomedial prefrontal cortex contribution to behavioral and nucleus accumbens neuronal responses to incentive cues. J. Neurosci. 28:5088-5098.

Ishikawa A, Ambroggi F, Nicola SM and Fields HL (2008) Contributions of the amygdala and the dorsal and ventral medial prefrontal cortex to incentive cue responding. Neuroscience 155:573-584.

Ambroggi F, Ishikawa A, Fields HL and Nicola SM (2008) Incentive cue encoding in the nucleus accumbens depends on basolateral amygdala inputs. Neuron 59:648-661.

Nicola SM (2010) The flexible approach hypothesis: Unification of effort and cue responding hypotheses for the role of nucleus accumbens dopamine in the activation of reward-seeking behavior. J. Neurosci. 8:16585-15600.

Ambroggi F, Ghazizadeh A, Nicola SM, Fields HL (2011) Roles of nucleus accumbens core and shell in incentive cue responding and behavioral inhibition. J. Neurosci. 31:6820-6830.

Du Hoffmann J, Kim JJ and Nicola SM (2011) An inexpensive drivable cannulated microelectrode array for simultaneous unit recording and drug infusion in the same brain nucleus of behaving rats. J. Neurophysiol. 106:1054-1064.

Lardeux S, Kim JJ and Nicola SM (2013) Intermittent access to sweet high-fat liquid induces increased palatability and motivation to consume in a rat model of binge consumption. Physiol. & Behav. 114-115:21-31.

McGinty VB, Lardeux S, Taha SA, Kim JJ and Nicola SM (2013) Invigoration of reward-seeking by cue and proximity encoding in the nucleus accumbens. Neuron 78:910-922.

Du Hoffmann J and Nicola SM (2014) Dopamine invigorates reward seeking by promoting cue-evoked excitation in the nucleus accumbens. J. Neurosci. 34:14349-14364.

Morrison S and Nicola SM (2014) Neurons in the nucleus accumbens promote selection bias for nearer objects. J. Neurosci. 34:4147-14162.

Lardeux S, Kim JJ and Nicola SM (2015) Intermittent-access binge consumption of sweet high-fat liquid does not require opioid or dopamine receptors in the nucleus accumbens. Behav. Brain Res. 292:194-208.

Morrison SE, Bamkole MA and Nicola SM (2015) Sign tracking, but not goal tracking, is resistant to outcome devaluation. Front. Neurosci. 9: article 468.

Du Hoffmann J and Nicola SM (2016) Activation of dopamine receptors in the nucleus accumbens promotes sucrose-reinforced cued approach behavior. Front. Behav. Neurosci. 10: article 144.

Nicola SM (2016) Reassessing wanting and liking in the study of mesolimbic influence on food intake. Am. J. Physiol. Comp. Reg. Integr. Physiol. 311:R811-R840.

Morrison SE, McGinty VB, du Hoffmann J and Nicola SM (2017) Limbic-motor integration by neural excitations and inhibitions in the nucleus accumbens. J. Neurophysiol. 118:2549-2567.

Caref K and Nicola SM (2018) Endogenous opioids in the nucleus accumbens promote approach to high-fat food in the absence of caloric need. eLife 7:e34955.

Vega-Villar M, Horvitz JC and Nicola SM (2019) NMDA receptor-dependent plasticity in the nucleus accumbens connects reward-predictive cues to approach responses. Nature Communications 10:4429.

Lederman J, Lardeux S and Nicola SM (2021) Vigor encoding in the ventral pallidum. eNeuro 8(4).

Kaźmierczak M and Nicola SM (2022) The arousal-motor hypothesis of dopamine function: evidence that dopamine facilitates reward seeking in part by maintaining arousal. Neuroscience 499:64-103.

Levcik D, Sugi AH, Aguilar-Rivera M, Pochapski JA, Baltazar G, Pulido LN, Villas-Boas C, Fuentes-Flores R, Nicola SM and da Cunha C (2023) Nucleus accumbens shell neurons encode the kinematics of reward approach locomotion. Neuroscience 524:181-196