Generally speaking, all perceptions of sound that do not correspond to actual external sources can be summed up under the term 'tinnitus'. This includes also brief periods (may be even only a few seconds) of ear noises which most people occasionally experience. In these 'transient' cases it is not seen as a problem at all and people are usually hardly aware of it. It only becomes a problem if the ear noises persists let's say for more than a day, because then the person begins to assume that something is seriously wrong. The resulting anxiety then makes it difficult to ignore the condition and the tinnitus can manifest itself as a chronic phenomenon. The ear noises can come in all possible forms, usually a pitched ringing or hissing, but low frequency hums, crackling noises or pulsating tones are not uncommon either. What is causing these noises in the absence of any external sources? Traditional medicine has always assumed that it has something to do with a damage of the hair cells in the inner ear resulting in 'phantom' signals being sent to the brain (which are then perceived as noises). However, research done in the last couple of decades suggests that the inner ear is in most cases not associated with the problem at all. The tinnitus is now considered to be mainly a regulatory problem of the auditory nervous system (see for instance the Tinnitus.org Website for more). The important point here is therefore that in most cases there is no damage of the inner ear associated with the tinnitus (not a permanent damage anyway). The problem is merely one of an imbalance in the auditory nervous system and how to overcome this. Thomas