Tinnitus emissions (SOAEs), which are faint high-frequency tones that are produced in the inner ear and can be measured in the ear canal with a sensitive microphone, may also cause tinnitus. About 8% of those with SOAEs and tinnitus have SOAE-linked tinnitus, while the percentage of all cases of tinnitus caused by SOAEs is estimated at about 4%. Some people experience a sound that beats in time with their pulse, known as "pulsatile tinnitus" or "vascular tinnitus". Pulsatile tinnitus is usually objective in nature, resulting from altered blood flow, increased blood turbulence near the ear, such as from atherosclerosis or venous
Black-body radiation logically determined solely by its own internal state. The causal effect of thermodynamic absorption on thermodynamic (spontaneous) emission is not direct, but is only indirect as it affects the internal state of the body. This means that at thermodynamic equilibrium the amount of every wavelength in every direction of thermal radiation emitted by a body at temperature "T", black or not, is equal to the corresponding amount that the body absorbs because it is surrounded by light at temperature "T". When the body is black, the absorption is obvious: the amount of light absorbed is all the light that hits