The auditory brainstem (ABR) test tells us how the inner ear, called the cochlea, and the brain pathways for hearing are working.
In the study, ABR measurements were carried out on 405 persons, 228 with tinnitus and 177 without tinnitus.
In people with constant tinnitus there was a clear difference in the measurements when compared to people without tinnitus or people who rated their tinnitus as occasional.
Researches have found that Brain-stem audiometry can be used to measure changes in the brain in people with constant tinnitus.
The researchers also followed over 20,000 people with no or varying degrees of tinnitus in order to track how the symptoms develop overtime.
Here, the researchers found that people with occasional tinnitus are at increased risk of developing constant tinnitus, especially if it recurs often.
The study also found that for those who already experience constant tinnitus, the chances are that the problem will persist.
The study was conducted in collaboration with the Karolinska University Hospital, Stockholm University in Sweden and the University of Bergen in Norway.