Figure 5: The average time course of signal intensity changes over subjects in the left and right “inferior vocalization” region of the primary motor cortex obtained from the ROI analysis during speaking a letter name silently and overtly (top), and during generating an animal name silently and overtly (bottom). Note that the magnitudes of the BOLD responses were approximately 50% less than ones observed in the “mouth, lips, and tongue” region of PMC during the same tasks (Figure 4). The ROI masks were defined by the most activated clusters, which were in the overt conditions. L:left; R: right.