The primary auditory cortex is the part of the cortex, specifically on the superior temporal gyrus, that receives auditory input. All six layers are present in A1 however 85% of all cells are pyramidal cells. The primary auditory cortex has a tonotopic map of the input from the medial geniculate body. The medial geniculate body receives input from the cochlea which has already been arranged tonotopically along the basilar membrane. The primary auditory cortex has a striped arrangement with one stripe consisting of neurons that are stimulated by input from both ears while the next stripe has neurons that are inhibited by one and excited by the second ear.