Cognitive functions such as metacognition and attention are necessary to make appropriate decisions in response to our surroundings. These cognitive functions are primarily controlled by the frontal association cortex, but it is still unclear what information is conveyed to subcortical regions. In this study, I aim to identify the signals transmitted from the frontal association cortex to the subcortical regions in the primate brain using fluorescence imaging tools, thereby clarifying the information processing mechanisms for executive functions.