Vicious cycle: the bidirectional relationship and pathophysiological mechanisms of tinnitus and sleep disturbance.

In sleep medicine and otology, the comorbidity of tinnitus and sleep disturbance may constitute a debilitating vicious cycle: intrusive phantom auditory perceptions disrupt sleep, whereas poor-quality, nonrestorative sleep further intensifies tinnitus-related distress and perceptual prominence, substantially compromising patients' health. Recent neurophysiological and clinical studies suggest that this comorbidity is not a simple causal relationship but may be driven by shared central nervous system mechanisms. Persistent central hyperexcitability, maladaptive neuroplasticity within auditory-limbic networks, and cognitive-behavioral processes resembling those of primary insomnia have been proposed as key pathophysiological drivers; multimodal interventions targeting these nodes may therefore be beneficial. This review systematically integrates clinical, psychological, and neurobiological evidence supporting this bidirectional association and delineates the reciprocal relationship and pathological mechanisms linking tinnitus and sleep disturbance. We also discuss the implications for future clinical management, advocate a shift toward comprehensive assessment and personalized multimodal intervention, and identify key opportunities and challenges for future research.