Assessment of Local Brain Activation
In five healthy human subjects, near-infrared spectroscopy (NIRS) and positron emission tomography (PET) examinations were performed simultaneously. Changes in [oxy-Hb], [deoxy-Hb] and [total-Hb] as measured by NIRS over the left forehead were compared to measurements of cerebral blood flow by PET during rest and during performance of a calculation task and a Stroop task.
When a penetration depth of near-infrared light of 0.9 cm into the brain cortex was assumed, a statistically significant correlation between changes in CBF and changes in [total-Hb] was found. These data confirm the validity of NIRS measurements in human adults.
KeywordsPositron Emission Tomography Cerebral Blood Flow Stroop Task Calculation Task NIRS Measurement
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