The indusium griseum, (supracallosal gyrus, gyrus epicallosus) consists of a thin membranous layer of

grey matter Grey matter is a major component of the central nervous system, consisting of neuronal cell bodies, neuropil (dendrites and unmyelinated axons), glial cells (astrocytes and oligodendrocytes), synapses, and capillaries. Grey matter is distingui ...

in contact with the upper surface of the

corpus callosum The corpus callosum (Latin for "tough body"), also callosal commissure, is a wide, thick nerve tract, consisting of a flat bundle of commissural fibers, beneath the cerebral cortex in the brain. The corpus callosum is only found in placental mam ...

and continuous laterally with the grey matter of the

cingulate cortex The cingulate cortex is a part of the brain situated in the medial aspect of the cerebral cortex. The cingulate cortex includes the entire cingulate gyrus, which lies immediately above the corpus callosum, and the continuation of this in the ci ...

and inferiorly with the hippocampus. It is vestigial in humans and is a remnant of the former position of the hippocampus in lower animals. On either side of the midline of the indusium griseum are two ridges formed by bands of longitudinally directed fibers known as the medial and lateral longitudinal striae. The indusium griseum is prolonged around the

splenium The corpus callosum (Latin for "tough body"), also callosal commissure, is a wide, thick nerve tract, consisting of a flat bundle of commissural fibers, beneath the cerebral cortex in the brain. The corpus callosum is only found in placental m ...

of the corpus callosum as a delicate layer, the fasciolar gyrus, which is continuous below with the surface of the

dentate gyrus The dentate gyrus (DG) is part of the hippocampal formation in the temporal lobe of the brain, which also includes the hippocampus and the subiculum. The dentate gyrus is part of the hippocampal trisynaptic circuit and is thought to contribute ...

. Toward the genu of the corpus callosum it curves down along the rostrum to form the

subcallosal gyrus The subcallosal gyrus (paraterminal gyrus, peduncle of the corpus callosum) is a narrow lamina on the medial surface of the hemisphere in front of the lamina terminalis, behind the parolfactory area, and below the rostrum of the corpus callosum. I ...

References

External links

* {{Authority control Gyri