Medium_particle_chart.jpg (JPEG Image, 2000 × 1517 pixels) Neuroscience Of Intelligence. Within the brain, areas dominated by cell bodies are called gray matter because of their grayish appearance (surprising).
While areas that are dominated by axons are called white matter, due to the whiteness caused by the myelin sheath that cover the axons. One of the most studied aspects of intelligence now is the role of gray matter and white matter. Brain and Behavior.