Figure 1.

Experimental setup. (a) During task performance, the participant's hand was occluded by a small rack, preventing direct observation. (b) Probe configuration for near‐infrared spectroscopy. The probe holders were placed over the frontal and parietal areas. The spatial registration of fNIRS maps onto MNI coordinate space. Recording channels on the frontal area were numbered from lower left to upper right position, and those on the parietal area were numbered from upper left to lower right position