Heritability of human "directed" functional connectome

Area of Science:

• Neuroscience
• Genetics
• Cognitive Science

Background:

• Brain functional connectivity patterns exhibit high heritability.
• The influence of genetic factors on the directionality of brain information flow remains unclear.
• Understanding heritability's modulation of directed functional connectivity is crucial for advancing connectome research.

Purpose of the Study:

• To investigate the heritability of directed functional connections in the human brain.
• To explore how genetic factors and shared environment influence the directionality of brain networks.
• To identify specific brain circuits where heritability impacts directed connectivity.

Main Methods:

• Utilized a state-space formulation of Granger causality (GC) to assess directed functional connections.
• Employed blind deconvolution methods to account for hemodynamic response function variability.
• Analyzed resting-state functional magnetic resonance imaging data from the Human Connectome Project (n=898), split into discovery and replication samples.

Main Results:

• Parieto-cerebellar, parieto-prefrontal, and posterior-cingulate to hippocampus connections demonstrated high and replicable heritability.
• Shared environmental factors had minimal influence on these highly heritable directed connections.
• Visuo-parietal and sensory-motor directed connectivity were significantly affected by shared environmental factors.

Conclusions:

• Heritability robustly influences directed connectivity in cortico-subcortical circuits relevant to cognition.
• Further research using task-based fMRI and GC is needed to confirm asymmetric genetic effects on cognitive networks.
• Findings contribute to understanding the genetic underpinnings of executive functions and learning through brain connectivity.