Functional Neuroimaging of Tinnitus: State-of-the-Art / 대한이비인후과학회지

ABSTRACT

Non-pulsatile subjective tinnitus is a phantom sound percept without any objective physical sound source. Recent advances in tinnitus research have suggested central rather than peripheral changes as the culprit of tinnitus perception. Moreover, researchers have shown that these central functional changes can be observed not only in the auditory cortex but also in non-auditory regions such as the frontal, parietal, and limbic areas in patients with tinnitus. In this regard, functional neuroimaging modalities such as positron emission tomography (PET), functional magnetic resonance imaging (fMRI), magnetoencephalography (MEG), and quantitative electroencephalography (qEEG) provided researchers with a window into the cerebral cortical activity orchestrating tinnitus. Among these methods, qEEG and MEG are advantageous over PET or fMRI with regard to temporal resolution, while PET and fMRI are advantageous over qEEG or MEG with regard to spatial resolution. In other words, there is no gold standard functional neuroimaging modality in the field of tinnitus, but these four modalities are complementary to one another. In this review article, these four representative functional neuroimaging modalities and their application to tinnitus research will be introduced. Moreover, future direction of functional neuroimaging research on the pathophysiology of tinnitus will be discussed briefly.