Distinct reward processing by subregions of the nucleus accumbens

Area of Science:

• Neuroscience
• Behavioral Neuroscience

Background:

• The nucleus accumbens (NAc) is crucial for motivation and reward.
• NAc subregions are increasingly recognized for differential roles in reward behaviors.
• Understanding individual neuron activity within NAc subregions is key.

Purpose of the Study:

• To investigate how reward is encoded by individual neurons in the medial (NAcMed) and lateral (NAcLat) shell of the NAc.
• To elucidate the functional and molecular differences between NAc subregions.

Main Methods:

• In vivo single-cell resolution calcium imaging in rodents.
• Optogenetic activation of specific neuronal populations (Nts-positive in NAcLat, Cartpt-positive in NAcMed).

Main Results:

• Diverse reward encoding patterns observed in NAcMed and NAcLat neurons.
• Reward consumption increased NAcLat activity but decreased NAcMed activity, with significant neuronal variability.
• Optogenetic activation of NAcLat neurons promoted positive reinforcement.
• Optogenetic activation of NAcMed neurons induced behavioral aversion.

Conclusions:

• Significant organizational and transcriptional differences exist between NAc subregions.
• These findings provide a framework for understanding NAc function in both normal and pathological states.
• Individual NAc neurons exhibit heterogeneous reward encoding strategies.