The mammalian forebrain consists of various macrostructures of which the cerebral cortex is the largest. This laminated sheet of gray matter comprises both the neocortex and other laminated components, including notably, the hippocampal formation. In addition there are nonlaminated structures in the forebrain, including the thalamus, and a variety of other entities (striatum, globus pallidus, subthalamus), which, together with the substantia nigra in the midbrain make up the complex known as the basal ganglia.