An assessment of hyperacusis, a frequent accompaniment of tinnitus, may also be made. The measured parameter is Loudness Discomfort Level (LDL) in dB, the subjective level of acute discomfort at specified frequencies over the frequency range of hearing. This defines a dynamic range between the hearing threshold at that frequency and the loudnes discomfort level. A compressed dynamic range over a particular frequency range is associated with subjectve hyperacusis. Normal hearing threshold is generally defined as 0–20 decibels (dB). Normal loudness discomfort levels are 85–90+ dB, with some authorities citing 100 dB. A dynamic range of 55 dB or less is indicative of hyperacusis.
The patients were assessed at the start of the study for their hearing ability and the severity of their tinnitus. The researchers assessed the degree of severity using established questionnaires, which looked at health-related quality of life, the psychological distress associated with tinnitus and how far it impaired their functioning. Using this information, researchers divided participants into four groups ranked on the severity of their condition.
The accepted definition of chronic tinnitus, as compared to normal ear noise experience, is five minutes of ear noise occurring at least twice a week. However, people with chronic tinnitus often experience the noise more frequently than this and can experience it continuously or regularly, such as during the night when there is less environmental noise to mask the sound.
We conducted a randomized, double-blind, placebo-controlled trial investigating the effects of the customized music-based sound therapy for reducing tinnitus. Participants (N = 50) who suffered from tinnitus were randomly allocated (with 1:1 ratio) to the treatment and placebo groups with assessments at baseline, 3, 6, and 12 months. The primary outcome was the differences in mean scores of the THI compared at four time intervals. Independent and paired samples t-tests were conducted to compare THI scores between and within groups, respectively.
Hyperacusis is a different, but related condition to tinnitus. People with hyperacusis have a high sensitivity to common, everyday environmental noise. In particular, sharp and high-pitched sounds are very difficult for people with hyperacusis to tolerate—sounds like the screeching of brakes, a baby crying or a dog barking, a sink full of dishes and silverware clanging. Many people with tinnitus also experience hyperacusis—but the two conditions don’t always go together.
Medication. Some medications are known to be ototoxic while others list tinnitus as a side effect without causing permanent damage to the ear structures. New medications come out so often that it is difficult to maintain an up to date listing; another option, if you are experiencing tinnitus and are curious if it could be your medication, is to talk to your pharmacist or look up your specific prescriptions online through a website such as www.drugs.com. You should never stop a medication without consulting with your physician, even if you think it may be contributing to your tinnitus.
Antidepressants are occasionally associated with tinnitus (Robinson, 2007). For example, Tandon (1987) reported that 1% of those taking imiprimine complained of tinnitus. In a double-blind trial of paroxetine for tinnitus, 3% discontinued due to a perceived worsening of tinnitus (Robinson, 2007). There are case reports concerning tinnitus as a withdrawal symptom from Venlafaxine and sertraline (Robinson, 2007). In our clinical practice, we have occasionally encountered patients reporting worsening of tinnitus with an antidepressant, generally in the SSRI family.
The researchers paired electrical stimulation of the vagus nerve — a large nerve that runs from the head to the abdomen — with the playing of a tone. Vagus nerve stimulation (VNS) is known to release chemicals that encourage changes in the brain. This technique, the scientists reasoned, might induce brain cells (neurons) to tune to frequencies other than the tinnitus one. For 20 days, 300 times a day, they played a high-pitched tone to 8 rats during VNS.
Ringing-in-the-ears or a fullness-of-the-head sensation are the most common symptoms of tinnitus. While ringing is the most common experience, the noise can also sound like a buzzing, hissing or whizzing sound. It can range from a low pitch to a high pitch and may be soft or loud at times. For some, tinnitus seems to get louder at night, just before sleep when no other sounds are competing with it. Tinnitus can remain constant or come and go intermittently. In severe cases, the ringing in the ears is loud enough to interfere with work or daily activity, whereas those with mild tinnitus can experience soft ringing that is no more than a minor annoyance.