1. An EEG marker of tinnitus suitable for diagnosing the presence of tinnitus in a tinnitus-suffering subject, wherein the marker is identified by a method comprising; presentation of a sine tone to a tinnitus-suffering subject; selection of a frequency of the sine tone upon presentation of the sine tone wherein the selected frequency matches an annoying sound pitch experienced by the subject; construction of a replica of the annoying sound pitch; and measurement of an EEG response of the subject to increasing intensity of the annoying sound pitch, wherein a peak amplitude of an auditory N100 component can be determined from the measure of the EEG thereby identifying the marker.