Common inhibitory prefrontal activation during inhibition of hand and foot responses.

Previous neuroimaging studies using manual Stop signal task showed the inhibitory-related areas in the pre-supplementary motor area (pre-SMA) and ventrolateral prefrontal cortex (VLPFC). However, most previous studies employed the manual response inhibition task and the brain representation of the response inhibition of the other body parts has been rarely studied. To further understand the precise brain processing of response inhibition, we performed the event-related fMRI study of Stop signal tasks using the hand and foot response to reveal the common prefrontal region relevant for response inhibition in 13 subjects. We found that the pre-SMA and bilateral VLPFC were commonly activated in successful response inhibition both for hand and foot tasks. The comparison of brain activation between hand and foot response inhibition tasks did not show any significant difference in the prefrontal area. In addition, there was no significant difference for peak coordinates in the pre-SMA and bilateral VLPFC between hand and foot tasks. These findings indicate the common neural network for inhibition of initiated responses regardless of the hand and foot.