Bundled-Optode Method in Functional Near-Infrared Spectroscopy

• Published in: PloS one Vol. 11; no. 10; p. e0165146
• Main Authors: Nguyen, Hoang-Dung, Hong, Keum-Shik, Shin, Yong-Il
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 27.10.2016; Public Library of Science (PLoS)
• Subjects: Adult; Biology and Life Sciences; Brain; Brain - metabolism; Brain - physiology; Engineering and Technology; Finger; Fingers; Fingers & toes; Hemodynamic responses; Hemodynamics; Hemoglobin; Hemoglobins; Hemoglobins - metabolism; Humans; I.R. radiation; Infrared spectra; Infrared spectroscopy; Light; Male; Medical imaging; Medicine and Health Sciences; Methods; Near infrared radiation; Near infrared spectroscopy; Neural networks; Neuroimaging; Noise; Optical Devices; Oxyhemoglobins - metabolism; Physical Sciences; Research and Analysis Methods; Sensors; Signal-To-Noise Ratio; Spectroscopy; Spectroscopy, Near-Infrared - instrumentation; Spectrum analysis; South Korea
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0165146

In this paper, a theory for detection of the absolute concentrations of oxy-hemoglobin (HbO) and deoxy-hemoglobin (HbR) from hemodynamic responses using a bundled-optode configuration in functional near-infrared spectroscopy (fNIRS) is proposed. The proposed method is then applied to the identification of two fingers (i.e., little and thumb) during their flexion and extension. This experiment involves a continuous-wave-type dual-wavelength (760 and 830 nm) fNIRS and five healthy male subjects. The active brain locations of two finger movements are identified based on the analysis of the t- and p-values of the averaged HbOs, which are quite distinctive. Our experimental results, furthermore, revealed that the hemodynamic responses of two-finger movements are different: The mean, peak, and time-to-peak of little finger movements are higher than those of thumb movements. It is noteworthy that the developed method can be extended to 3-dimensional fNIRS imaging.