Large-Scale Network Coupling with the Fusiform Cortex Facilitates Future Social Motivation.

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Functional Neuroimaging

Background:

• Large-scale functional brain networks are crucial for cognitive processing.
• Understanding the interaction between domain-general networks and focal brain regions is key to explaining thought and action coordination.

Purpose of the Study:

• Investigate how the default-mode network (DMN) and executive control network (ECN) influence task performance through coupling with other cortical regions.
• Examine the neural mechanisms underlying reaction time (RT) variations preceding behavior.

Main Methods:

• fMRI was used to measure brain activity during a modified monetary incentive delay (MID) task.
• Independent components analysis (ICA) and network-based psychophysiological interaction (nPPI) analysis were integrated.
• Participants viewed social and nonsocial images, and connectivity changes preceding RT variations were analyzed.

Main Results:

• Participants exhibited slower reaction times (RTs) after viewing social images compared to nonsocial images.
• Increased coupling between the ECN and the fusiform gyrus (FG), including the fusiform face area (FFA), was observed following social reward stimuli.
• The magnitude of this increased coupling correlated with the subsequent slowing of RT.

Conclusions:

• Large-scale brain networks dynamically interact with focal cortical regions to orchestrate behavior.
• The ECN's coupling with the FFA plays a role in modulating behavioral responses to social stimuli.
• These findings elucidate the neural basis of how domain-general networks influence specific cognitive and behavioral outcomes.