Central Abnormalities in Idiopathic Tinnitus With Mild Hearing Loss: Selective Attention and Preprocessing Dysfunction.

OBJECTIVES

To verify the abnormal brain electrical activity of idiopathic tinnitus through auditory event-related potentials and elucidate the impact of mild hearing loss.

DESIGN

Auditory event-related potentials were collected from 74 patients with idiopathic tinnitus as the primary complaint (divided into a normal hearing group of 39 and a mild hearing loss group of 35 based on hearing level) and 37 healthy volunteers. Various auditory event-related potential indicators were compared among the groups, and the correlation between these indicators and the clinical characteristics of idiopathic tinnitus patients was analyzed.

RESULTS

Idiopathic tinnitus patients with normal hearing have increased P1 amplitude, delayed P300 latency, decreased P300 amplitude, and decreased mismatch negativity (MMN) amplitude. Idiopathic tinnitus patients with mild hearing loss have further reduced P300 amplitude and delayed MMN latency. In addition, the P300 latency of idiopathic tinnitus patients is significantly correlated with the duration of tinnitus and Tinnitus Handicap Inventory (THI) score, the P300 amplitude is significantly correlated with the Pittsburgh Sleep Quality Index (PSQI) score, and the MMN latency is significantly correlated with the duration of tinnitus.

CONCLUSION

Patients with idiopathic tinnitus exhibit abnormalities in multiple auditory event-related potentials, with mild hearing loss exacerbating some of these abnormalities. Idiopathic tinnitus and mild hearing loss may lead to selective attention and preprocessing dysfunction.