Cerebral Blood Flow Changes in Non-Auditory Tinnitus

A new brain imaging study provides a clear physical link between a vascular condition and the persistent experience of non-auditory tinnitus. Researchers from Capital Medical University in Beijing identified specific patterns of reduced brain blood flow in patients whose tinnitus is associated with cerebral venous congestion, a condition that impairs blood drainage from the brain. These blood flow changes were directly connected to how long patients had tinnitus and the severity of their associated symptoms like poor sleep and depression.

### The Study: Connecting Blood Flow to Tinnitus Symptoms

The research team, led by Lu Liu, Milan Jia, and Hongxia Li, recruited 87 participants for a cross-sectional comparison. They grouped subjects into three categories: 34 patients with cerebral venous congestion and non-auditory tinnitus (NAT+), 17 patients with the same vascular condition but no tinnitus (NAT-), and 36 healthy controls.

To measure brain blood flow, the scientists used a non-invasive MRI technique called multi-delay pseudo-continuous arterial spin labeling (ASL). This method quantifies cerebral blood flow (CBF) and adjusts for arterial transit time, giving a detailed map of perfusion across the entire brain. The team then analyzed CBF across 166 brain regions. They also collected clinical data on tinnitus duration, sleep quality, and symptoms of anxiety and depression to look for correlations with the brain scans.

### Key Findings: A Left-Hemisphere Pattern Linked to Suffering

The results, published in *Brain Imaging and Behavior*, revealed a distinct pattern. Patients in the NAT+ group showed significant CBF reductions compared to both the NAT- group and healthy controls. The reductions were not random; they clustered in the left hemisphere and specific brain regions.

Areas with notably lower blood flow included the insula (involved in interoception and emotion), the paracentral lobule, and the precentral gyrus (both part of the sensorimotor network). Further network analysis showed that the affected regions belong to critical brain systems responsible for attention, sensorimotor processing, the default mode network, and cerebellar functions.

The clinical correlations were striking. The researchers found that reduced CBF in NAT+ patients was associated with longer tinnitus duration, poorer scores on sleep quality assessments, and higher depression scores. This suggests the degree of blood flow disruption is not just a marker of disease but is related to the burden of the condition on the patient’s life. For a broader look at how tinnitus alters brain physiology, our article on Cerebral Blood Flow Changes in Tinnitus provides additional context.

### What This Means for Understanding Tinnitus

This study moves beyond theories and identifies a measurable, physical brain change in a subset of tinnitus patients. The primary implication is that for some individuals, non-auditory tinnitus may be a neurological symptom of an underlying vascular problem—cerebral venous congestion. When veins in the neck or brain are narrowed (internal jugular vein stenosis or cerebral venous sinus stenosis), blood drainage is impaired. This congestion appears to lead to a secondary reduction in fresh arterial blood flow to specific brain regions.

The affected networks offer clues about the symptoms. Reduced perfusion in attention and sensorimotor networks could relate to the perceived salience and bodily awareness of the tinnitus sound. Changes in regions linked to the default mode network, which is active during self-reflection, may connect to the intrusive, persistent nature of the condition. The strong link to sleep and mood disturbances, centered on the insula, shows how the vascular issue can trigger a wider cascade of suffering. This pathophysiological perspective is explored in more detail in our related piece, Cerebral Blood Flow in Tinnitus: Venous Congestion Link.

### Practical Implications and Future Directions

For clinicians and patients, this research underscores the importance of considering vascular health in tinnitus assessment, especially when tinnitus is non-auditory and accompanied by other neurological symptoms. It argues for a more holistic diagnostic approach that could include imaging of cerebral veins. The direct correlation between CBF and symptom severity also suggests that improving cerebral perfusion—whether through potential venous treatments or other means—could theoretically alleviate both the tinnitus and its associated burdens.

The authors note that their findings need confirmation in larger, longitudinal studies. Future research should track whether treatments aimed at relieving venous congestion can normalize cerebral blood flow patterns and reduce tinnitus severity. Understanding this vascular pathway also opens questions about its role in related sound sensitivity conditions. While distinct, the brain network changes observed share some overlap with those seen in hyperacusis, suggesting potential common physiological pathways worth investigating.

**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](https://doi.org/10.1007/s11682-026-01144-8). PMID: [41957332](https://pubmed.ncbi.nlm.nih.gov/41957332/).