This study investigates the neural basis of inhibitory control using event-related functional MRI (ER-fMRI). The researchers aimed to identify the cortical regions involved in inhibiting prepotent motor responses. Fourteen right-handed subjects participated in a task where they had to inhibit responses to certain letters (lures) while responding to others (targets). The ER-fMRI design allowed for the isolation of activation associated with correct response inhibitions, minimizing contamination from response errors and other extraneous processes. The results showed that response inhibition was lateralized to the right hemisphere, with significant activations in the middle and inferior frontal gyri, frontal limbic area, anterior insula, and inferior parietal lobe. These findings suggest that response inhibition is not limited to ventral frontal regions but involves a distributed cortical network. Correlational analyses revealed a positive relationship between faster response times to targets and activation in the right inferior frontal gyrus and left inferior parietal lobule during response inhibition. The study also identified a motor circuit associated with response execution, including regions such as the left primary motor cortex, supplementary motor area (SMA), striatum, and cerebellum. The lack of overlap between activation maps for response inhibitions and responses further confirmed the specificity of the observed network for response inhibition. The findings highlight the importance of the right hemisphere in inhibitory control and suggest that response inhibition involves a distributed network of primarily frontal and right hemisphere regions. This distributed network may include both ventral and dorsal prefrontal regions, with the ventral regions likely playing a more critical role in signaling the inhibition signal, while the dorsal regions are involved in integrating this information and executing appropriate action commands.This study investigates the neural basis of inhibitory control using event-related functional MRI (ER-fMRI). The researchers aimed to identify the cortical regions involved in inhibiting prepotent motor responses. Fourteen right-handed subjects participated in a task where they had to inhibit responses to certain letters (lures) while responding to others (targets). The ER-fMRI design allowed for the isolation of activation associated with correct response inhibitions, minimizing contamination from response errors and other extraneous processes. The results showed that response inhibition was lateralized to the right hemisphere, with significant activations in the middle and inferior frontal gyri, frontal limbic area, anterior insula, and inferior parietal lobe. These findings suggest that response inhibition is not limited to ventral frontal regions but involves a distributed cortical network. Correlational analyses revealed a positive relationship between faster response times to targets and activation in the right inferior frontal gyrus and left inferior parietal lobule during response inhibition. The study also identified a motor circuit associated with response execution, including regions such as the left primary motor cortex, supplementary motor area (SMA), striatum, and cerebellum. The lack of overlap between activation maps for response inhibitions and responses further confirmed the specificity of the observed network for response inhibition. The findings highlight the importance of the right hemisphere in inhibitory control and suggest that response inhibition involves a distributed network of primarily frontal and right hemisphere regions. This distributed network may include both ventral and dorsal prefrontal regions, with the ventral regions likely playing a more critical role in signaling the inhibition signal, while the dorsal regions are involved in integrating this information and executing appropriate action commands.