Blood Flow Dynamics: Training Your Brain's Vascular Rhythms
Overview
In this livestream, Dr. Hill explored vasomotion—the rhythmic 10-second oscillations of blood vessels in the brain—and how these vascular patterns can be trained using HEG (hemoencephalography) neurofeedback. Drawing from breakthrough 2024 research, he explained how passive infrared HEG training may work by teaching the brain's vascular network to oscillate more coherently, improving both cognitive function and waste clearance through the glymphatic system.
The session provided a mechanistic update to HEG training, moving beyond vague explanations like "training neurovascular coupling" to specific hypotheses about entraining vascular oscillators and optimizing brain maintenance systems.
Key Research Findings from 2024
Vasomotion Creates Traveling Waves
Broggini et al. (2024) used two-photon imaging in awake mice to track arterial diameter changes across large sections of cortex in real-time. They discovered that vasomotion—the 0.1 Hz (once every 10 seconds) rhythmic contraction and relaxation of blood vessels—forms coordinated traveling waves across the brain rather than random local oscillations.
These waves dominate resting perfusion patterns, suggesting vasomotion isn't decorative but serves as load-bearing infrastructure for brain metabolism and maintenance.
Vascular Oscillations Are Trainable
Sasaki et al. (2024) demonstrated that vasomotion patterns are plastic and can be entrained through repeated stimulation. Their entrainment protocols improved waste clearance through the glymphatic system—the brain's cleanup mechanism that relies on coordinated blood flow oscillations to create pressure gradients that flush metabolic waste.
This finding provides a direct mechanistic link between vascular training and brain health maintenance.
Stress and Stroke Disrupt Vascular Rhythms
Research by Zhao et al. (2024) and Turner et al. (2025) revealed that blood vessels lose their rhythmic coordination after stroke, and chronic stress damages the small population of nNOS neurons (less than 1% of cortex) that act as vascular pacemakers. These neurons rhythmically release nitric oxide to coordinate regional blood vessel dilation.
When these pacemaker neurons are damaged or exhausted, you lose both the amplitude and coordination of vasomotion—potentially explaining why chronic stress degrades cognitive function over time.
The HEG Training Mechanism Refined
Beyond "Training Activation"
Traditional explanations for HEG effectiveness focused on "increasing prefrontal activation" or "improving neurovascular coupling." Dr. Hill proposed a more specific mechanism: HEG training uses repeated, spaced trials (up-regulate prefrontal blood flow, get feedback, rest, repeat) that structurally mirror the entrainment protocols shown to train vasomotion in animal models.
Over 10-20 sessions, you're teaching the prefrontal vascular network to oscillate more coherently and respond more efficiently to neural demand.
Why Passive Infrared Works
Passive infrared HEG measures thermal radiation from blood flow oscillations—essentially watching the 10-second vasomotion cycles in real-time. Because these oscillations are much slower than brain waves (0.1 Hz vs 8-40+ Hz), lower resolution tools can effectively track and train them.
The training involves learning to sustain increased blood flow in the prefrontal cortex, which likely strengthens the coordination between neural demand and vascular response.
Clinical Applications and Evidence
Migraine Reduction
Multiple studies show HEG training reduces migraine frequency and severity. Dr. Hill hypothesized this works because migraines may involve dysregulated vasomotion—when the coordinated 10-second vascular oscillations become chaotic or dampened, it could trigger the cascade of events leading to migraine episodes.
Training vascular rhythm coherence through HEG may restore the smooth coordination needed to prevent migraine triggers.
Attention and Executive Function
HEG training consistently improves attention and executive function, likely by optimizing prefrontal blood flow dynamics. When vasomotion operates smoothly, it ensures consistent fuel delivery and waste removal in the brain regions most critical for sustained attention and cognitive control.
Anxiety and Depression Benefits
Clinical data shows HEG reduces anxiety and depression symptoms. This may work through two pathways: improved prefrontal regulation of emotional processing, and enhanced glymphatic waste clearance that removes inflammatory metabolites linked to mood disorders.
Q&A Highlights
Question: How does this relate to other neurofeedback approaches?
Traditional EEG neurofeedback trains electrical brain wave patterns, while HEG trains the underlying vascular support system. Both can be complementary—you might use EEG to train specific cognitive states and HEG to optimize the metabolic infrastructure supporting those states.
Question: Can you train vasomotion without specialized equipment?
While HEG provides direct feedback on vascular oscillations, other practices might indirectly train these systems. Meditation, controlled breathing, and potentially even sauna/cold exposure could influence vascular rhythmicity, though without the precision of targeted biofeedback.
Question: How long does it take to see results from HEG training?
Clinical studies typically show benefits after 10-20 sessions. Dr. Hill noted that unlike some forms of neurofeedback that can show immediate effects, HEG training appears to work through gradual strengthening of vascular coordination—more like physical exercise for your blood vessels.
The Bigger Picture: Cognitive Cadence
This vasomotion research connects to Dr. Hill's broader "cognitive cadence" framework—the idea that brain function depends on nested rhythmic timescales. The 10-second vasomotion rhythm represents one crucial temporal scale that supports cognitive function.
When chronic stress kills the pacemaker neurons or disrupts these oscillations, cognitive performance degrades. Training the rhythm through targeted interventions like HEG may restore one fundamental layer of brain timing.
Takeaways
- Vasomotion is trainable: Your brain's blood flow oscillations aren't fixed—they can be strengthened and coordinated through targeted practice
- HEG training has a specific mechanism: Rather than vaguely "increasing activation," it likely trains vascular rhythm coherence and responsiveness
- Stress damages vascular pacemakers: Chronic stress kills the neurons that coordinate blood flow rhythms—another reason stress management is crucial for cognitive health
- Multiple benefits from one system: Training vascular oscillations may simultaneously improve attention, reduce migraines, and enhance brain waste clearance
- Precision matters: While other practices may influence vascular function, biofeedback tools like HEG provide direct training of these specific oscillatory patterns
For practitioners interested in HEG training, Dr. Hill noted he's working on updating the technology stack to make these tools more accessible, with new solutions expected in 2026.