Prefrontal brain activation during stop-signal response inhibition: an event-related functional near-infrared spectroscopy study.

Previous lesion and neuroimaging studies have shown that the frontal lobes play an important role in response inhibition. In the present study event-related functional near-infrared spectroscopy (NIRS) was applied to investigate cerebral blood oxygenation in the right and left prefrontal cortex (PFC) in 15 male participants during the performance of a stop-change paradigm. Data analysis showed stronger brain activation in the left and right PFC during successful and failed stopping of initiated responses in comparison to a condition without stopping. Changes in cerebral blood oxygenation were more pronounced in the right than in the left PFC. No substantial activation changes were found during successful or failed changing of initiated responses (response inhibition and subsequent response re-engagement). The findings indicate that NIRS is suitable for the functional identification of prefrontal activation during the inhibition of initiated responses and provide further support for the contribution of the PFC to response inhibition.