Tinnitus activity in the limbic system and autonomic nervous system, thus increasing tinnitus awareness and annoyance. There are two types of tinnitus: "subjective tinnitus" and "objective tinnitus". Tinnitus is usually subjective, meaning that there is no sound detectable by other means. Subjective tinnitus has also been called "tinnitus aurium", "non-auditory" or "non-vibratory" tinnitus. In very rare cases tinnitus can be heard by someone else using a stethoscope, and in less rare – but still uncommon – cases it can be measured as a spontaneous otoacoustic emission (SOAE) in the ear canal. In such cases it is objective tinnitus, also called "pseudo-tinnitus"
Tinnitus masker trying to sleep or relax, as it is within these quiet environments that the tinnitus is at its most noticeable. They commonly take the form of CD or MP3 recordings, or bedside noise generators. When used in conjunction with a sound pillow (which contains small embedded speakers) they can mask a person's tinnitus sounds without disturbing his/her partner. These masker devices use soothing natural sounds such as ocean surf, rainfall or synthetic sounds such as white noise, pink noise, or brown noise to help the auditory system become less sensitive to tinnitus and promote relaxation by reducing the contrast between