Reward-related regions form a preferentially coupled system at rest

Area of Science:

• Neuroimaging
• Cognitive Neuroscience
• Systems Neuroscience

Background:

• Neuroimaging reveals specific striatal and orbitofrontal cortex (OFC) regions active during reward processing.
• Resting-state functional connectivity (RSFC) studies show the brain's organization into coherent functional systems at rest.

Purpose of the Study:

• To characterize the systems-level organization of brain reward regions at rest using RSFC.
• To identify distinct functional systems associated with reward processing.
• To investigate the connectivity of reward regions with other brain systems.

Main Methods:

• Utilized seed-based and graph-theory RSFC approaches.
• Identified candidate reward regions based on nucleus accumbens (NAcc) and OFC connectivity peaks.
• Merged identified regions with a previously established set (Power et al., 2011) for system membership analysis.

Main Results:

• A distinct, preferentially coupled RSFC system comprising key reward regions (NAcc, OFC, ventromedial prefrontal cortex) was identified.
• This reward system demonstrated stability across connectivity thresholds and significant overlap with task-based reward study findings.
• The reward system exhibited differential connectivity with cognitive control and self-regulation systems (fronto-parietal, cingulo-opercular, default), with NAcc connecting to cingulo-opercular/default and OFC to fronto-parietal.

Conclusions:

• A distinct functional brain system for reward processing at rest has been delineated.
• This reward system interacts with cognitive control networks, suggesting potential neural mechanisms underlying self-regulation and appetitive behaviors.
• The identified connectivity profiles offer a basis for future research into individual differences related to addiction and self-regulation failure.