Tinnitus and Cerebral Blood Flow Explained

Patients with a specific type of tinnitus linked to vascular issues show a distinct pattern of reduced brain blood flow, according to a new neuroimaging study. This reduction correlates with longer symptom duration, worse sleep, and increased depression.

Connecting Vascular Problems to Brain Perfusion

The research, led by Lu Liu, Milan Jia, and colleagues at Capital Medical University in Beijing, focused on patients with cerebral venous congestion (CVC). This condition, which includes internal jugular vein or cerebral venous sinus stenosis, impedes blood drainage from the brain. The team hypothesized that this backup could lead to secondary reductions in the fresh, oxygenated blood flow delivered by arteries—a state measured as cerebral blood flow (CBF). Their study specifically examined patients experiencing non-auditory tinnitus (NAT), a form of the condition often described as a whooshing or pulsating sound believed to be of vascular or muscular origin.

As lead author Lu Liu and the team explain, while arterial spin labeling (ASL) MRI primarily measures arterial perfusion, it can reveal the global perfusion consequences of a venous pathology. “This study investigates CBF alterations in CVC patients, particularly those with NAT,” they wrote in Brain Imaging and Behavior.

How the Study Measured Brain Blood Flow

The researchers conducted a cross-sectional study with 87 participants divided into three groups: 34 CVC patients with NAT (NAT+), 17 CVC patients without NAT (NAT-), and 36 healthy controls. They used a sophisticated MRI technique called multi-delay pseudo-continuous arterial spin labeling to quantify blood flow throughout the entire brain. This method adjusts for the speed at which blood arrives in brain tissue, providing a more accurate CBF map.

They then analyzed CBF across the whole brain and within 170 specific regions defined by a standard anatomical atlas. The team also collected clinical data on tinnitus duration, sleep quality, anxiety, depression, and cognitive function to see if blood flow levels correlated with these symptoms.

A Distinct Pattern of Reduced Blood Flow Emerges

The results revealed a clear and specific pattern. Patients in the NAT+ group showed significant CBF reductions compared to both the NAT- group and healthy controls. The decreases were most pronounced in the brain’s left hemisphere and affected key regions including the insula, paracentral lobule, and precentral gyrus.

“Reduced CBF in NAT+ patients was correlated with longer tinnitus duration, poorer sleep quality, and worse depression scores,” the authors reported. This means the lower the blood flow in these areas, the more severe these specific clinical problems tended to be. Further network analysis showed the affected regions were part of major functional brain systems: the attention network, sensorimotor network, default mode network, and cerebellar networks. This connects the vascular findings to known circuits involved in perception, self-awareness, and motor control. For more on the cerebellum’s involvement in auditory disorders, see our article on Cerebellar Insights for Tinnitus and Misophonia.

Implications for Understanding and Treating Tinnitus

These findings offer a more detailed physiological model for some cases of tinnitus. They directly link a vascular problem—impaired venous drainage—to measurable changes in brain perfusion and specific patient symptoms. The study moves beyond simply noting an association; it identifies the likely path from vascular obstruction to reduced brain function in specific circuits and the resulting clinical experience of tinnitus, sleep disruption, and low mood.

Practically, this work supports the clinical investigation of vascular factors in patients with non-auditory, pulsatile tinnitus. It suggests that treatments aimed at improving cerebral venous drainage or addressing the consequences of reduced perfusion in the identified brain networks could be explored. The correlation with symptom severity also provides a potential biomarker—CBF in the insula or precentral gyrus—that could be used to track disease progression or treatment response.

This research aligns with a growing body of work examining blood flow changes in hearing-related disorders. Our previous coverage of Tinnitus Linked to Altered Brain Blood Flow discusses related findings, and the distinct brain patterns seen here further highlight how different triggers for sound sensitivity may involve unique neural pathways, a topic explored in our comparison of Misophonia vs Hyperacusis: Brain fMRI Differences.

A New Direction for a Complex Symptom

The study by Liu, Jia, and their team provides concrete evidence for a venous-related mechanism in non-auditory tinnitus. By identifying a characteristic pattern of reduced cerebral blood flow that ties directly to symptom severity, the research offers a new framework for understanding this condition. It confirms that for a subset of patients, tinnitus is not solely an ear or auditory nerve problem, but a clear neurovascular issue with broad consequences for brain function and mental health. Future studies with larger groups and longitudinal designs will be needed to confirm if improving venous flow can reverse these perfusion deficits and alleviate symptoms.

Source: Liu L, Jia M, Li H, et al. Cerebral blood flow alterations in non-auditory tinnitus: implications for cerebral venous congestion pathophysiology. Brain Imaging Behav 2026;20(2):72. doi:10.1007/s11682-026-01144-8. PMID: 41957332.