Investigation for brain mechanisms of tinnitus using positron emission tomography(PET).

残余抑制是听觉刺激停止后耳鸣的短暂抑制。我们使用正电子发射断层扫描研究了三名耳蜗植入耳鸣患者和六名正常听力对照者的残留抑制脑区。在耳鸣和耳鸣残余抑制两种情况下测量并比较区域脑血流量。残余抑制时，右侧颞上回（Brodmann区21区和38区）被激活，而耳鸣患者在耳鸣感知时，右侧小脑被激活。在正常对照中未观察到明显的激活。我们的研究结果表明，耳鸣和残余抑制与听觉高阶加工、记忆和注意的皮质网络有关。

Residual inhibition is a transient suppression of tinnitus after auditory stimulation has stopped. We used positron emission tomography to study brain regions underlying residual inhibition in three tinnitus patients with cochlear implants and six normal hearing controls. Regional cerebral blood flow was measured and compared under two conditions : with tinnitus and during the residual inhibition of tinnitus. The right anterior middle and superior temporal gyri (Brodmann areas 21 and 38) were activated during residual inhibition, while the right cerebellum was activated during tinnitus perception in the tinnitus patients. No significant activation was observed in the normal controls. Our results suggest that tinnitus and residual inhibition are related to cortical networks of auditory higher-order processing, memory and attention.