Hyperoxia modified activation-induced blood oxygenation level-dependent response of human visual cortex (V1): an event-related functional magnetic resonance imaging study

To investigate the effect that hyperoxia has on the blood oxygenation level -dependent (BOLD) response to visual stimulation of human V1, an event-rela ted functional magnetic resonance imaging technique was applied. The event- related paradigm consisted of 2 s of stimulation by a checkerboard reversin g at a frequency of 8 Hz, followed by 18 s of control scans. The peak heigh t and peak time of the BOLD response curves were compared under normoxic an d hyperoxic conditions. It was found that the peak height was larger and th e peak time shorter for hyperoxia than for normoxia. These results suggest that hyperoxia modified the activation-induced hemodynamic response of huma n V1. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.