Sulcal variability of twins

Area of Science:

• Neuroscience
• Human Anatomy
• Genetics

Background:

• Neocortical sulci are complex folds in the human brain.
• Understanding the factors influencing sulcal pattern development is crucial for neuroscience.
• Previous research has explored brain morphology but detailed sulcal analysis is less common.

Purpose of the Study:

• To investigate the genetic and environmental influences on neocortical sulcal patterns.
• To determine if sulcal shape is predetermined and to what extent.
• To explore the relationship between overall brain shape and specific sulcal patterns.

Main Methods:

• Utilized three-dimensional, depth-encoded line representations of neocortical sulci.
• Analyzed magnetic resonance image (MRI) datasets from 19 pairs of normal monozygotic twins and matched unrelated twin pairs.
• Developed new image analysis techniques to automatically extract 'sulcal cuts' from MRI data.

Main Results:

• Monzygotic co-twins exhibited significantly higher sulcal similarity than unrelated twin pairs.
• Deeper sulci showed greater similarity than superficial sulci, with this effect being stronger in related twins.
• Individuals with similar overall brain shapes also displayed more similar sulcal patterns.
• The left posterior lateral hemispheric surface appeared to be the least variable brain region.

Conclusions:

• The shape of deep neocortical sulci is more strongly genetically predetermined than superficial sulci.
• Both genetic and shared environmental factors likely contribute to sulcal pattern development.
• Brain shape and sulcal patterns may arise from related developmental processes.
• Further research is needed to disentangle the precise genetic and environmental contributions.