Genetic and environmental contributions to brain activation during calculation

Area of Science:

• Neuroscience
• Behavioral Genetics
• Cognitive Neuroscience

Background:

• Twin studies suggest genetic underpinnings for mathematical abilities.
• Previous research identified candidate genes but not specific brain regions influenced by genetics during number manipulation.

Purpose of the Study:

• To investigate the genetic and environmental contributions to brain activation and functional lateralization during mental calculation.
• To identify specific brain regions involved in mathematical abilities that are under genetic influence.

Main Methods:

• Functional magnetic resonance imaging (fMRI) data from 19 monozygotic (MZ) and 13 dizygotic (DZ) adult twin pairs during a mental calculation task.
• Analysis of brain activation and functional lateralization in predefined regions of interest (ROIs).
• Heritability estimation using MZ-DZ correlation comparisons and fitting an ACE model.

Main Results:

• Genetic influence was observed in bilateral posterior superior parietal lobules (PSPL), right intraparietal sulcus (IPS), and a left superior frontal region.
• The left inferior parietal cortex (IPC) showed genetic influence, with its deactivation correlating with behavioral calculation scores.
• Shared environmental factors significantly impacted the lateralization of activation within the intraparietal sulcus.

Conclusions:

• Specific brain networks involved in number processing are subject to genetic control.
• The findings provide candidate phenotypes for future genetic association studies on mathematical abilities.
• This research elucidates the interplay between genetics and environment in shaping neural networks for number processing.