A. Villringer et al., NEAR-INFRARED SPECTROSCOPY (NIRS) - A NEW TOOL TO STUDY HEMODYNAMIC-CHANGES DURING ACTIVATION OF BRAIN-FUNCTION IN HUMAN ADULTS, Neuroscience letters, 154(1-2), 1993, pp. 101-104
In healthy human adults, cerebral concentrations of oxygenated hemoglo
bin ([HbO2]) and deoxygenated hemoglobin ([HbR]) were assessed during
brain activation using near infrared spectroscopy (NIRS). Measurements
were made either in the frontal cortex (n=10) during performance of c
ognitive tasks or in the occipital cortex (n=6) during visual stimulat
ion (flash-light exposure, picture observation). The typical findings
during brain activation were an increase in [HbO2] and a decrease in [
HbR]. We demonstrate that these findings are not due to alterations in
skin blood flow. NIRS is a simple bedside technique for the assessmen
t of hemodynamic alterations accompanying brain activation.