Neurofeedback training (allowing an individual to view some type of external indicator of brain activity and attempt to exert control over it) has the potential to reduce the severity of tinnitus or even eliminate it, according to a new study by Wright State University in the US.
Tinnitus is the perception of noise, often ringing, in the ear. The condition is very common, affecting approximately one in five people. As sufferers start to focus on it more, they become more frustrated and anxious, which in turn makes the noise seem worse. The primary auditory cortex, the part of the brain where auditory input is processed, has been implicated in tinnitus-related distress.
During the study, researchers looked at a novel potential way to treat tinnitus by having people use neurofeedback training to turn their focus away from the sounds in their ears.
Matthew Sherwood, the study’s lead author, said: ‘The idea is that in people with tinnitus there is an over-attention drawn to the auditory cortex, making it more active than in a healthy person.’
‘Our hope is that tinnitus sufferers could use neurofeedback to divert attention away from their tinnitus and possibly make it go away.’
The researchers had 18 healthy volunteers with normal hearing undergo five fMRI-neurofeedback training sessions. Study participants were given earplugs through which white noise could be introduced for periods of time. The earplugs also served to block out the scanner noise.
‘We started with alternating periods of sound and no sound in order to create a map of the brain and find areas that produced the highest activity during the sound phase,’ Dr. Sherwood said. ‘Then we selected the voxels that were heavily activated when sound was being played.’
The participants then participated in the fMRI-neurofeedback training phase while inside the MRI scanner. They received white noise through their earplugs and were able to view the activity in their primary auditory cortex as a bar on a screen. Each fMRI-neurofeedback training run contained eight blocks separated into a 30-second ‘relax’ period followed by a 30-second ‘lower’ period. Participants were instructed to watch the bar during the relax period and actively attempt to lower it by decreasing primary auditory cortex activity during the lower phase.
The researchers gave the participants techniques to help them do this, such as trying to divert attention from sound to other sensations like touch and sight.
A control group of nine individuals were provided fake neurofeedback visuals – they performed the same tasks as the other group, but the feedback came not from them but from a random participant. By performing the exact same procedures with both groups using either real or fake neurofeedback, the researchers were able to distinguish the effect of real neurofeedback on control of the primary auditory cortex.
The study represents the first time fMRI-neurofeedback training has been applied to demonstrate that there is a significant relationship between control of the primary auditory cortex and attentional processes.
‘Ultimately, we’d like take what we learned from MRI and develop a neurofeedback program that doesn’t require MRI to use, such as an app or home-based therapy that could apply to tinnitus and other conditions,’ Dr. Sherwood said.