Tinnitus is the conscious perception of acoustic stimuli that cannot be attributed to an external sound source.Since the phantom sound of tinnitus is usually perceived in the ear, the generator of tinnitus has traditionally been considered to be located in the inner ear.However, sectioning of the auditory nerve failed to abolish tinnitus complaints in the majority of subjects.This fact has drawn the attention of neuroscientific research to the central nervous system.A number of functional imaging studies demonstrated increased neuronal activity in the inferior colliculus, the auditory thalamus and the auditory cortex.Therefore it was suggested that tinnitus is generated in the central auditory system.However, recent progress in neuroscientific research suggests that hyperactivity within primary sensory areas is not sufficient for conscious perception.Rather synchronized coactivation of frontal and parietal areas seems to be necessary and with increasing tinnitus duration activity in the auditory cortex may become less relevant.Tinnitus distress in turn may be related to coactivation of emotion processing networks in the frontal cortex or the limbic system.