Cerebellum. Light micrograph of a cross section through the human cerebellum. The cerebellum is highly folded and contains white matter at its core, known as the medulla (white). The medulla consists of axon nerve fibres. Surrounding this is the folded cortex (brown) made of two layers. Next to the medulla is the granular layer of the cortex (brown, grainy) packed with nerve cells. A thicker molecular layer (light brown), rich in nerve fibre networks surrounds this. Purkinje cells (black dots) occur between these cortical layers. The cerebellum controls body posture and coordinates muscle movement and balance. Magnification: x13 at 6x7cm size.