Impact of Changes in Systemic Physiology on fNIRS/NIRS Signals: Analysis Based on Oblique Subspace Projections Decomposition

  • Nassim NasseriEmail author
  • Alexander Caicedo
  • Felix Scholkmann
  • Hamoon Zohdi
  • Ursula Wolf
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 1072)


Measurements of cerebral and muscle oxygenation (StO2) and perfusion ([tHb]) with functional near-infrared spectroscopy (fNIRS) and near infrared spectroscopy (NIRS), respectively, can be influenced by changes in systemic physiology. The aim of our study was to apply the oblique subspace projections signal decomposition (OSPSD) to find the contribution from systemic physiology, i.e. heart rate (HR), electrocardiography (ECG)-derived respiration (EDR) and partial pressure of carbon dioxide (pCO2) to StO2 and [tHb] signals measured on the prefrontal cortex (PFC) and calf muscle. OSPSD was applied to two datasets (n1 = 42, n2 = 79 measurements) from two fNIRS/NIRS speech studies. We found that (i) all StO2 and [tHb] signals contained components related to changes in systemic physiology, (ii) the contribution from systemic physiology varied strongly between subjects, and (iii) changes in systemic physiology generally influenced fNIRS signals on the left and right PFC to a similar degree.


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  • Nassim Nasseri
    • 1
    Email author
  • Alexander Caicedo
    • 2
    • 3
    • 4
  • Felix Scholkmann
    • 1
    • 5
  • Hamoon Zohdi
    • 1
  • Ursula Wolf
    • 1
  1. 1.Institute of Complementary Medicine, University of BernBernSwitzerland
  2. 2.Department of Electrical Engineering ESATSTADIUS KU LeuvenLeuvenBelgium
  3. 3.imecLeuvenBelgium
  4. 4.Research Foundation Flanders (FWO)BrusselsBelgium
  5. 5.Biomedical Optics Research Laboratory, Department of NeonatologyUniversity Hospital Zurich, University of ZurichZurichSwitzerland

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