Abstract
As it does with any continuing stimulus, the response to a prolonged tone or group of tones will eventually disappear from consciousness. How long this takes to happen will depend on the nature of the stimulus: in the case of a single tone, obviously on its loudness, but also on its structure, on whether this is simply sinusoidal, or compound. In any event, the tone must be repeated or a different tone sounded if a melodic formulation is to arise.