According to researchers at the University of Illinois at Urbana-Champaign, some patients who suffer from tinnitus, or ringing in the ears, use different brain regions when processing emotional information.

Fatima Husain, PhD

Fatima Husain, PhD

Tinnitus, which affects nearly one-third of adults over age 65 and can cause varying degrees of disruption to daily life, may develop as part of age-related hearing loss or from significant noise exposure or a traumatic injury. While many tinnitus patients are forced to limit daily activities as a direct result of debilitating symptoms, others adapt to the condition. A recent study conducted by Fatima Husain, PhD, a speech and hearing science and neuroscience professor at the University of Illinois, was aimed at finding the reasons for this variation in adaptive responses to the condition.

Edward McAuley, MD, PhD

Edward McAuley, MD, PhD

“We are trying to understand how the brain adapts to having tinnitus for a very long time,” said Husain, who conducted the research with kinesiology and community health professor Edward McAuley, MD, PhD, and graduate students Jake Carpenter-Thompson and Sara Schmidt. Carpenter-Thompson is lead author on the study’s paper, which was published in the December 14, 2015 edition of the journal PLOS ONE.

Husain’s research uses functional magnetic resonance imaging (fMRI), an imaging tool that enables researchers to see changes in blood oxygen levels in the brain during an activity. As outlined in a July 3, 2014 article in Hearing Review, Husain’s team previously used fMRI to study how the brain processes emotion in patients with mild tinnitus compared to people without the condition. While in the scanner for the earlier study, participants listened to and rated pleasant, unpleasant, and neutral sounds (ie, children laughing, babies crying, and people babbling in the background). The findings of that study revealed that, in contrast to those without tinnitus, patients with mild tinnitus showed greater engagement of different areas in the brain when processing emotional sounds.

To further understand this altered brain activation, Husain conducted the more recent fMRI study. Because some patients adjust to the ringing in the ears while others do not, Husain and the team wanted to identify the differences among tinnitus patients. In addition to using fMRI scans, Husain’s team measured the severity of tinnitus according to associated distress with a series of surveys and questionnaires assessing hearing, attention, emotion, and sleep.

It was discovered that patients with lower tinnitus distress used an altered brain pathway to process emotional information. The path did not rely on the amygdala, commonly believed to play an important role in emotion processing in the brain. Patients who were better adapted to their tinnitus symptoms appeared to use more of the brain’s frontal lobe, a region critical for attention, planning, and impulse control. The researchers hypothesize that the greater activation of the frontal lobe in these patients might be helping to control their emotional responses to tinnitus, reducing distress.

A second aim of the study was to evaluate possible interventions to help patients reduce tinnitus distress. The researchers report that physical activity might influence emotion processing and help to improve quality of life for those who experience distress from tinnitus. Future research studies by Husain and her colleagues will reportedly explore active duty service members, a group that is greatly affected by trauma-induced tinnitus.

For additional information related to this study, read the article at Science.mic that highlights musicians and how their brains may process sound differently. Mic Staff Writer Max Plenke’s interview with Dr Husain provides additional details.

Source: University of Illinois