Grey Matter vs White Matter

In this horizontal or axial section of human brain, the distinction between white matter and grey matter is well defined. The green arrows in this image point to the cerebral cortex, a rim of grey matter. The green arrows point to white matter. The somata or cell bodies of neurons are found in grey matter. The white matter lacks neuron cell bodies, and is comprised largely of axons. Many of the axons in white matter are myelinated. The lipid-rich myelin contributes to the whitish color of white matter. The brain specimens used in a gross anatomy lab are usually preserved in formalin or something similar. Consequently, the difference in color between grey and white matter is not as pronounced.