Coupling between Intrinsic Prefrontal HbO2 and Central EEG Beta Power Oscillations in the Resting Brain

• Published in: PloS one Vol. 7; no. 8; p. e43640
• Main Authors: Pfurtscheller, Gert, Daly, Ian, Bauernfeind, Günther, Müller-Putz, Gernot R.
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 24.08.2012; Public Library of Science (PLoS)
• Subjects: Adult; Analysis; Bernard, Claude (1813-1878); Biology; Blood pressure; Blood Pressure - physiology; Brain; Brain - physiology; Brain Mapping; Brain research; Brain Waves - physiology; Coupling; Cross correlation; EEG; Electroencephalography; Excitability; Female; Health aspects; Heart rate; Heart Rate - physiology; Hemodynamics; Hemodynamics - physiology; Humans; I.R. radiation; Infrared spectra; Infrared spectroscopy; Knowledge discovery; Laboratories; Male; Medicine; Near infrared radiation; Near infrared spectroscopy; Neurons; Neurosciences; Oscillations; Oxyhemoglobin; Physiology; Prefrontal cortex; Sensorimotor system; Signal Processing, Computer-Assisted; Spectroscopy, Near-Infrared; Spectrum analysis; Austria
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0043640

There is increasing interest in the intrinsic activity in the resting brain, especially that of ultraslow and slow oscillations. Using near-infrared spectroscopy (NIRS), electroencephalography (EEG), blood pressure (BP), respiration and heart rate recordings during 5 minutes of rest, combined with cross spectral and sliding cross correlation calculations, we identified a short-lasting coupling (duration [Formula: see text] s) between prefrontal oxyhemoglobin (HbO2) in the frequency band between 0.07 and 0.13 Hz and central EEG alpha and/or beta power oscillations in 8 of the 9 subjects investigated. The HbO2 peaks preceded the EEG band power peaks by 3.7 s in 6 subjects, with moderate or no coupling between BP and HbO2 oscillations. HbO2 and EEG band power oscillations were approximately in phase with BP oscillations in the 2 subjects with an extremely high coupling (squared coherence [Formula: see text]) between BP and HbO2 oscillation. No coupling was identified in one subject. These results indicate that slow precentral (de)oxyhemoglobin concentration oscillations during awake rest can be temporarily coupled with EEG fluctuations in sensorimotor areas and modulate the excitability level in the brains' motor areas, respectively. Therefore, this provides support for the idea that resting state networks fluctuate with frequencies of between 0.01 and 0.1 Hz (Mantini et.al. PNAS 2007).