ArticlePhilosophical transactions of the Royal Society of London. Series B, Biological sciences2021
When the human brain goes diving: using near-infrared spectroscopy to measure cerebral and systemic cardiovascular responses to deep, breath-hold diving in elite freedivers.
Article in Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 19 papers.
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Who cites it
19 citing papers in PubMed, 29 citations in OpenAlex.
- Heart rate and sub-blubber temperature in harbour seals (Phoca vitulina) measured during the moult and post-moult using implantable loggers.Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology · 2026Article
- Advances in breath-hold diving research: a state-of-the-art review.European journal of applied physiology · 2026Review
- Cognitive risk during underwater exposure: from environmental stressors to assessment and context-aware monitoring.Frontiers in physiology · 2026Review
- Somatosensory and prefrontal cortex activity relates to emotional outcomes and hair cortisol concentration in chronic postsurgical pain.Scientific reports · 2025Article
- Cerebral hemodynamic and systemic physiological changes in trained freedivers completing sled-assisted dives to two different depths.American journal of physiology. Regulatory, integrative and comparative physiology · 2024Article
- Blood oxygen transport and depletion in diving emperor penguins.The Journal of experimental biology · 2024Article
- Physiological monitoring to prevent diving disorders.Frontiers in physiology · 2024Review
- Self-calibrated pulse oximetry algorithm based on photon pathlength change and the application in human freedivers.Journal of biomedical optics · 2023Article
- Unlocking the depths: multiple factors contribute to risk for hypoxic blackout during deep freediving.European journal of applied physiology · 2023Article
- Underwater pulse oximetry reveals increased rate of arterial oxygen desaturation across repeated freedives to 11 metres of freshwater.Diving and hyperbaric medicine · 2023Article
- Dopamine/BDNF loss underscores narcosis cognitive impairment in divers: a proof of concept in a dry condition.European journal of applied physiology · 2023Article
- Future trends in measuring physiology in free-living animals.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2021Article
- What is physiologging? Introduction to the theme issue, part 2.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2021Article
- Shining new light on sensory brain activation and physiological measurement in seals using wearable optical technology.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2021Article
- Introduction to the theme issue: Measuring physiology in free-living animals.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2021Article
- Fur seals do, but sea lions don't - cross taxa insights into exhalation during ascent from dives.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2021Article
- The New Era of Physio-Logging and Their Grand Challenges.Frontiers in physiology · 2021Article
- Association Between Arterial Oxygen Saturation and Lung Ultrasound B-Lines After Competitive Deep Breath-Hold Diving.Frontiers in physiology · 2021Article
- Near-Infrared Spectroscopy as a Tool for Marine Mammal Research and Care.Frontiers in physiology · 2021Article
Corrections and comments
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Authors and funding
14 authors at 5 institutions in 5 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Continuous measurements of haemodynamic and oxygenation changes in free living animals remain elusive. However, developments in biomedical technologies may help to fill this knowledge gap. One such technology is continuous-wave near-infrared spectroscopy (CW-NIRS)-a wearable and non-invasive optical technology. Here, we develop a marinized CW-NIRS system and deploy it on elite competition freedivers to test its capacity to function during deep freediving to 107 m depth. We use the oxyhaemoglobin and deoxyhaemoglobin concentration changes measured with CW-NIRS to monitor cerebral haemodynamic changes and oxygenation, arterial saturation and heart rate. Furthermore, using concentration changes in oxyhaemoglobin engendered by cardiac pulsation, we demonstrate the ability to conduct additional feature exploration of cardiac-dependent haemodynamic changes. Freedivers showed cerebral haemodynamic changes characteristic of apnoeic diving, while some divers also showed considerable elevations in venous blood volumes close to the end of diving. Some freedivers also showed pronounced arterial deoxygenation, the most extreme of which resulted in an arterial saturation of 25%. Freedivers also displayed heart rate changes that were comparable to diving mammals both in magnitude and patterns of change. Finally, changes in cardiac waveform associated with heart rates less than 40 bpm were associated with changes indicative of a reduction in vascular compliance. The success here of CW-NIRS to non-invasively measure a suite of physiological phenomenon in a deep-diving mammal highlights its efficacy as a future physiological monitoring tool for human freedivers as well as free living animals. This article is part of the theme issue 'Measuring physiology in free-living animals (Part II)'.
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