Annals of Biomedical Engineering

, Volume 41, Issue 2, pp 223–237

Hemodynamic Response to Repeated Noxious Cold Pressor Tests Measured by Functional Near Infrared Spectroscopy on Forehead

  • Zeinab Barati
  • Patricia A. Shewokis
  • Meltem Izzetoglu
  • Robi Polikar
  • George Mychaskiw
  • Kambiz Pourrezaei

DOI: 10.1007/s10439-012-0642-0

Cite this article as:
Barati, Z., Shewokis, P.A., Izzetoglu, M. et al. Ann Biomed Eng (2013) 41: 223. doi:10.1007/s10439-012-0642-0


The objective of this research was to assess the utility of a simple near infrared spectroscopy (NIRS) technology for objective assessment of the hemodynamic response to acute pain. For this exploration, we used functional near infrared spectroscopy (fNIRS) to measure the hemodynamic response on the forehead during three trials of a cold pressor test (CPT) in 20 adults. To measure hemodynamic changes at the superficial tissues as well as the intracranial tissues, two configurations of ‘far’ and ‘near’ source-detector separations were used. We identified two features that were found to be fairly consistent across all subjects. The first feature was the change of total hemoglobin (THb) concentration in a given condition divided by the duration of that condition \( {\text{THb}}^{\prime} \). Statistical analyses revealed that during the first CPT trial \( {\text{THb}}^{\prime} \) significantly changed from its baseline value in all channels. Also, adaptation to repeated CPTs was observed in both \( {\text{THb}}^{\prime} \) parameter and the reported post-stimulus pain rating scores. The second feature was the difference between the maximum and the minimum of the evoked changes in the THb concentration (ΔTHb). A significant correlation was observed between the post-stimulus pain rating score and ΔTHb at all channels. An asymmetrical activity was observed only at the ‘far’ channels. These results suggest that fNIRS can potentially be used as a reliable technique for the assessment of the hemodynamic response to tonic pain induced by the CPT.


Numerical rating scalePainSympathetic nervous system



Confidence interval


Cold pressor test


Cerebrospinal fluid


False discovery rate


Light emitting diode


Functional data analysis


Functional near infrared spectroscopy






Laterality quotient


Numerical rating scale


Total hemoglobin

Copyright information

© Biomedical Engineering Society 2012

Authors and Affiliations

  • Zeinab Barati
    • 1
  • Patricia A. Shewokis
    • 1
    • 2
  • Meltem Izzetoglu
    • 1
  • Robi Polikar
    • 3
  • George Mychaskiw
    • 4
  • Kambiz Pourrezaei
    • 1
  1. 1.School of Biomedical Engineering, Science and Health SystemsDrexel UniversityPhiladelphiaUSA
  2. 2.College of Nursing and Health ProfessionsDrexel UniversityPhiladelphiaUSA
  3. 3.Department of Electrical and Computer EngineeringRowan UniversityGlassboroUSA
  4. 4.Department of AnesthesiaNemours Children’s HospitalOrlandoUSA