Cerebrovascular response to cognitive tasks and hyperventilation measured by multi-channel near-infrared spectroscopy.

We assessed the cerebral blood volume response in the bilateral frontal area in 10 healthy subjects during the design fluency task, verbal fluency task, and hyperventilation measured by 24-channel near-infrared spectroscopy. Oxygenated and total hemoglobin increased during the design fluency task and verbal fluency task and decreased during hyperventilation bilaterally, while deoxygenated hemoglobin did not change. The test-retest reliability examined in five subjects was acceptable to assess the cerebrovascular response to cognitive tasks and hyperventilation.