Affect and the brain's functional organization: a resting-state connectivity approach

Area of Science:

• Neuroscience
• Affective Science
• Cognitive Neuroscience

Background:

• The neural organization of affective processing remains debated, with hypotheses including right-hemispheric dominance, valence-specific lateralization, unified emotional networks, or discrete emotion regions.
• Previous research offers limited evidence, necessitating further investigation into brain networks underlying emotional experiences.

Purpose of the Study:

• To investigate intrinsic functional connectivity patterns associated with positive and negative affect.
• To test competing hypotheses regarding the brain's organization of emotional processing.

Main Methods:

• Examined functional connectivity using voxelwise analysis across 200 regions-of-interest in 65 participants.
• Correlated intrinsic functional connectivity with Positive and Negative Affective Schedule (PANAS) scores, avoiding task-related confounds.
• Assessed whole-brain connectivity patterns to identify shared and unique networks for positive and negative affect.

Main Results:

• Both positive and negative affect showed overlapping functional connectivity patterns involving the medial prefrontal cortex, anterior cingulate, visual cortex, and cerebellum.
• Distinct connectivity patterns were identified for positive and negative affective domains.
• A significant right hemispheric dominance was observed for negative affect connectivity.

Conclusions:

• Emotional processing is organized within a predominantly right-hemispheric network.
• This network exhibits affect-specific organizational elements, integrating shared and unique connectivity patterns.
• Findings support a nuanced model of affective brain organization, moving beyond simplistic lateralization or unified network theories.