Described as persistent ear noise with no corresponding outside noise source, tinnitus is a condition that approximately 18% of Australians will suffer from at some point in their lives. As many sufferers will tell you, the constant ringing of tinnitus can be a major source of pain, frustration and depression.
So it will come as no surprise to many that a new study has found that people with tinnitus process emotions differently to those who don’t.
While previous research demonstrated tinnitus was associated with increased stress, irritability, anxiety and depression, there was little published experimental research to explain these findings. The new study, published in Brain Research by the University of Illinois, aimed to rectify this by using fMRI (functional magnetic resonance imaging) brain scans to show areas of the brain actively responding to stimulation.
Three groups were used in the study – some with mild-to-moderate hearing loss combined with mild tinnitus, some with mild-to-moderate hearing loss and no tinnitus, and a control group of age-matched people with no tinnitus or hearing loss. Each participant listened to 30 unpleasant, 30 neutral and 30 pleasant sounds.
Overall, the participants with tinnitus exhibited slower emotional reactions and their scans demonstrated less activity in the amygdala, which is the part of the brain most commonly associated with emotions. However, those with tinnitus also showed more activity in both the parahippocampus and, two other areas of the brain often associated with emotions.
To explain these results, researchers suggest that tinnitus patients’ brains have adjusted to process both regular and phantom sounds, redistributing them around different cerebral areas, like a form of unconscious multi-tasking. “We thought that because people with tinnitus constantly hear a bothersome, unpleasant stimulus, they would have an even higher amount of activity in the amygdala when hearing these sounds, but it was lesser,” says Professor Fatima Husain, the study’s author. “Because they’ve had to adjust to the sound, some plasticity in the brain has occurred. They have had to reduce this amygdala activity and reroute it to other parts of the brain because the amygdala can’t be active all the time.”
Professor Husain hopes that these findings will be built on with her group’s future research, eventually leading to solutions that could ultimately improve the lives of those living with tinnitus. “Audiologists and clinicians are aware that tinnitus affects emotional aspects, too, and we want to make them aware that these effects are occurring so they can better help their patients,” she says.
Do you suffer from tinnitus? Speak to a Connect Hearing specialist about your treatment options.