Dopamine D1-Receptor Organization Contributes to Functional Brain Architecture

Area of Science:

• Neuroscience
• Neuroimaging
• Molecular Psychiatry

Background:

• Cortical function exhibits a gradient from sensory to transmodal areas.
• This functional axis may correlate with regional neurotransmitter expression patterns.
• Dopamine D1-receptors (D1DR) are crucial for neural modulation and gain.

Purpose of the Study:

• To test if D1DR organization aligns with the functional architecture of the cortex.
• To investigate if D1DR co-expression modulates functional crosstalk between brain regions.
• To explore the relationship between D1DR density and cortical hierarchy differentiation.

Main Methods:

• Utilized the largest available database of dopamine D1DR-PET and MRI scans (N=180).
• Analyzed spatial correspondence between D1DR organization and functional connectivity gradients.
• Examined individual differences in D1DR density and their association with functional differentiation.

Main Results:

• D1DR organization mirrors a unimodal-transmodal hierarchy, closely matching the principal functional connectivity gradient.
• Individual variations in D1DR density correlate with functional differentiation at the apex of the cortical hierarchy.
• Spatial co-expression of D1DR primarily influences within-network couplings, not between-network interactions.

Conclusions:

• Dopamine D1-receptor organization provides a biomolecular foundation for the brain's functional architecture.
• D1DR density and its spatial distribution are key determinants of functional differentiation and network interactions.
• This study elucidates the role of D1DR in bridging molecular and functional organization in the human brain.