Highlights
- Regional brain oxygenation increased by 81%.
- A brain blood flow-related proxy increased by 202%.
- Two heart rate variability measures increased by 104% and 124%.
- Peripheral circulation measures also changed, including a 33% increase in peripheral pulse transit time.
A 60-year-old participant completed one 20-minute AVACEN session as part of an exploratory study in an assisted living facility. Researchers measured several physiological parameters immediately before and after the session, along with the participant’s perceived wellness.
More oxygenated blood detected in the assessed brain region
The brain depends on blood to continuously deliver the oxygen and nutrients needed to support normal activity. Researchers therefore measured regional cerebral blood oxygenation, which provides information related to the presence of oxygenated blood in the brain region being assessed.
After the session, this measure increased by 81%, from 13 to 23.5.
A separate cerebral blood flow proxy—an indirect, non-invasive measure related to blood flow in the brain—increased by 202%, from 129 to 389.
These changes are interesting because adequate blood flow and oxygen delivery are fundamental to normal brain function. However, the measurements do not show that cognition or brain performance improved, since those outcomes were not measured in this case.
How flexibly was the heart responding?
Researchers also measured heart rate variability, or HRV. HRV describes the small variations in time between one heartbeat and the next.
Although it might seem that a perfectly regular heartbeat would be ideal, the heart normally adjusts continually in response to breathing and other physiological demands. HRV therefore provides information about how the autonomic nervous system is regulating the heart.
Two common HRV measurements changed substantially: SDNN increased by 104% and RMSSD by 124%. Mean heart rate decreased slightly by 4%.
The participant’s autonomic measures also shifted slightly toward greater parasympathetic—or “rest-and-recover”—influence.
Changes in peripheral circulation and vascular response
Peripheral circulation-related measurements increased as well. Bilateral Flow Gain, a measure used to observe circulation-related changes on both sides of the body, increased by 117% on the left and 73% on the right. Perfusion Index, which provides information related to blood flow reaching peripheral tissues, increased by 31%.
Another measurement, peripheral pulse transit time (PPT), increased from 100.9 to 134 ms, representing a 33% increase. PPT reflects the time it takes for the pulse wave generated by the heartbeat to travel through the peripheral circulation. Changes in this measure provide researchers with additional information about vascular and circulatory behavior following the session.
Taken together, the increases in Flow Gain, Perfusion Index, and PPT suggest that the session was followed by a measurable short-term peripheral circulation and vascular response.
The participant also reported feeling better
The participant’s total wellness score increased from 35 to 49, representing a 40% improvement immediately after the session.
This case represents one person’s short-term response. While it cannot predict how others will respond, the simultaneous changes in brain-related, cardiovascular, circulation-related, and self-reported measures make it an interesting observation for future research.
