Sex differences in functional cortical organization reflect differences in network topology rather than cortical...

Area of Science:

• Neuroscience
• Human Anatomy
• Brain Imaging

Background:

• Sex differences in brain size are well-documented.
• The impact of these anatomical variations on intrinsic brain function is not fully understood.

Purpose of the Study:

• To investigate the association between sex differences in intrinsic cortical functional organization and cortical morphometry.
• To explore if brain size, microstructure, and connectivity influence functional organization differences between sexes.

Main Methods:

• Computed a low-dimensional representation of functional cortical organization, the sensory-association axis.
• Identified sex differences in this functional organization.
• Assessed associations with cortical morphometric properties (surface area, microstructure, geodesic distance).

Main Results:

• Widespread sex differences were found in the sensory-association axis of functional organization.
• These functional differences were not systematically linked to differences in total surface area, microstructural organization, or geodesic distance.
• Functional sex differences were associated with variations in functional connectivity profiles and network topology.

Conclusions:

• Sex differences in intrinsic cortical functional organization are not solely explained by differences in cortical morphometry.
• Functional connectivity and network topology play a significant role in sex-specific brain function.
• These findings highlight the complexity of sex differences in the brain beyond anatomical measures.